Merge pull request #45 from AeneasVerif/son_merge_types

Big cleanup

65 files changed, 7898 insertions, 8568 deletions

diff --git a/compiler/AssociatedTypes.ml b/compiler/AssociatedTypes.ml
index 581e218c..2442f93a 100644
--- a/compiler/AssociatedTypes.ml
+++ b/compiler/AssociatedTypes.ml
@@ -6,157 +6,92 @@
     enforced by local clauses (i.e., clauses of the shape [where Trait1::T = Trait2::U]).
  *)
 
-module T = Types
-module TU = TypesUtils
-module V = Values
-module E = Expressions
-module A = LlbcAst
-module C = Contexts
+open Types
+open TypesUtils
+open Values
+open LlbcAst
+open Contexts
 module Subst = Substitute
-module L = Logging
-module UF = UnionFind
-module PA = Print.EvalCtxLlbcAst
 
 (** The local logger *)
-let log = L.associated_types_log
+let log = Logging.associated_types_log
 
-let trait_type_ref_substitute (subst : ('r, 'r1) Subst.subst)
-    (r : 'r C.trait_type_ref) : 'r1 C.trait_type_ref =
-  let { C.trait_ref; type_name } = r in
+let trait_type_ref_substitute (subst : Subst.subst) (r : trait_type_ref) :
+    trait_type_ref =
+  let { trait_ref; type_name } = r in
   let trait_ref = Subst.trait_ref_substitute subst trait_ref in
-  { C.trait_ref; type_name }
+  { trait_ref; type_name }
 
-(* TODO: how not to duplicate below? *)
-module RTyOrd = struct
-  type t = T.rty
+module TyOrd = struct
+  type t = ty
 
-  let compare = T.compare_rty
-  let to_string = T.show_rty
-  let pp_t = T.pp_rty
-  let show_t = T.show_rty
+  let compare = compare_ty
+  let to_string = show_ty
+  let pp_t = pp_ty
+  let show_t = show_ty
 end
 
-module STyOrd = struct
-  type t = T.sty
+module TyMap = Collections.MakeMap (TyOrd)
 
-  let compare = T.compare_sty
-  let to_string = T.show_sty
-  let pp_t = T.pp_sty
-  let show_t = T.show_sty
-end
-
-module RTyMap = Collections.MakeMap (RTyOrd)
-module STyMap = Collections.MakeMap (STyOrd)
-
-(* TODO: is it possible not to have this? *)
-module type TypeWrapper = sig
-  type t
-end
-
-(* TODO: don't manage to get the syntax right so using a functor *)
-module MakeNormalizer
-    (R : TypeWrapper)
-    (RTyMap : Collections.Map with type key = R.t T.region T.ty)
-    (M : Collections.Map with type key = R.t T.region C.trait_type_ref) =
-struct
-  let compute_norm_trait_types_from_preds
-      (trait_type_constraints : R.t T.region T.trait_type_constraint list) :
-      R.t T.region T.ty M.t =
-    (* Compute a union-find structure by recursively exploring the predicates and clauses *)
-    let norm : R.t T.region T.ty UF.elem RTyMap.t ref = ref RTyMap.empty in
-    let get_ref (ty : R.t T.region T.ty) : R.t T.region T.ty UF.elem =
-      match RTyMap.find_opt ty !norm with
-      | Some r -> r
-      | None ->
-          let r = UF.make ty in
-          norm := RTyMap.add ty r !norm;
-          r
-    in
-    let add_trait_type_constraint (c : R.t T.region T.trait_type_constraint) =
-      let trait_ty = T.TraitType (c.trait_ref, c.generics, c.type_name) in
-      let trait_ty_ref = get_ref trait_ty in
-      let ty_ref = get_ref c.ty in
-      let new_repr = UF.get ty_ref in
-      let merged = UF.union trait_ty_ref ty_ref in
-      (* Not sure the set operation is necessary, but I want to control which
-         representative is chosen *)
-      UF.set merged new_repr
-    in
-    (* Explore the local predicates *)
-    List.iter add_trait_type_constraint trait_type_constraints;
-    (* TODO: explore the local clauses *)
-    (* Compute the norm maps *)
-    let rbindings =
-      List.map (fun (k, v) -> (k, UF.get v)) (RTyMap.bindings !norm)
-    in
-    (* Filter the keys to keep only the trait type aliases *)
-    let rbindings =
-      List.filter_map
-        (fun (k, v) ->
-          match k with
-          | T.TraitType (trait_ref, generics, type_name) ->
-              assert (generics = TypesUtils.mk_empty_generic_args);
-              Some ({ C.trait_ref; type_name }, v)
-          | _ -> None)
-        rbindings
-    in
-    M.of_list rbindings
-end
-
-(** Compute the representative classes of trait associated types, for normalization *)
-let compute_norm_trait_stypes_from_preds
-    (trait_type_constraints : T.strait_type_constraint list) :
-    T.sty C.STraitTypeRefMap.t =
-  (* Compute the normalization map for the types with regions *)
-  let module R = struct
-    type t = T.region_var_id
-  end in
-  let module M = C.STraitTypeRefMap in
-  let module Norm = MakeNormalizer (R) (STyMap) (M) in
-  Norm.compute_norm_trait_types_from_preds trait_type_constraints
-
-(** Compute the representative classes of trait associated types, for normalization *)
 let compute_norm_trait_types_from_preds
-    (trait_type_constraints : T.rtrait_type_constraint list) :
-    T.ety C.ETraitTypeRefMap.t * T.rty C.RTraitTypeRefMap.t =
-  (* Compute the normalization map for the types with regions *)
-  let module R = struct
-    type t = T.region_id
-  end in
-  let module M = C.RTraitTypeRefMap in
-  let module Norm = MakeNormalizer (R) (RTyMap) (M) in
+    (trait_type_constraints : trait_type_constraint list) : ty TraitTypeRefMap.t
+    =
+  (* Compute a union-find structure by recursively exploring the predicates and clauses *)
+  let norm : ty UnionFind.elem TyMap.t ref = ref TyMap.empty in
+  let get_ref (ty : ty) : ty UnionFind.elem =
+    match TyMap.find_opt ty !norm with
+    | Some r -> r
+    | None ->
+        let r = UnionFind.make ty in
+        norm := TyMap.add ty r !norm;
+        r
+  in
+  let add_trait_type_constraint (c : trait_type_constraint) =
+    (* Sanity check: the type constraint can't make use of regions - Remark
+       that it would be enough to only visit the field [ty] of the trait type
+       constraint, but for safety we visit all the fields *)
+    assert (trait_type_constraint_no_regions c);
+    let trait_ty = TTraitType (c.trait_ref, c.generics, c.type_name) in
+    let trait_ty_ref = get_ref trait_ty in
+    let ty_ref = get_ref c.ty in
+    let new_repr = UnionFind.get ty_ref in
+    let merged = UnionFind.union trait_ty_ref ty_ref in
+    (* Not sure the set operation is necessary, but I want to control which
+       representative is chosen *)
+    UnionFind.set merged new_repr
+  in
+  (* Explore the local predicates *)
+  List.iter add_trait_type_constraint trait_type_constraints;
+  (* TODO: explore the local clauses *)
+  (* Compute the norm maps *)
   let rbindings =
-    Norm.compute_norm_trait_types_from_preds trait_type_constraints
+    List.map (fun (k, v) -> (k, UnionFind.get v)) (TyMap.bindings !norm)
   in
-  (* Compute the normalization map for the types with erased regions *)
-  let ebindings =
-    List.map
+  (* Filter the keys to keep only the trait type aliases *)
+  let rbindings =
+    List.filter_map
       (fun (k, v) ->
-        ( trait_type_ref_substitute Subst.erase_regions_subst k,
-          Subst.erase_regions v ))
-      (M.bindings rbindings)
-  in
-  (C.ETraitTypeRefMap.of_list ebindings, rbindings)
-
-let ctx_add_norm_trait_stypes_from_preds (ctx : C.eval_ctx)
-    (trait_type_constraints : T.strait_type_constraint list) : C.eval_ctx =
-  let norm_trait_stypes =
-    compute_norm_trait_stypes_from_preds trait_type_constraints
+        match k with
+        | TTraitType (trait_ref, generics, type_name) ->
+            assert (generics = empty_generic_args);
+            Some ({ trait_ref; type_name }, v)
+        | _ -> None)
+      rbindings
   in
-  { ctx with C.norm_trait_stypes }
+  TraitTypeRefMap.of_list rbindings
 
-let ctx_add_norm_trait_types_from_preds (ctx : C.eval_ctx)
-    (trait_type_constraints : T.rtrait_type_constraint list) : C.eval_ctx =
-  let norm_trait_etypes, norm_trait_rtypes =
+let ctx_add_norm_trait_types_from_preds (ctx : eval_ctx)
+    (trait_type_constraints : trait_type_constraint list) : eval_ctx =
+  let norm_trait_types =
     compute_norm_trait_types_from_preds trait_type_constraints
   in
-  { ctx with C.norm_trait_etypes; norm_trait_rtypes }
+  { ctx with norm_trait_types }
 
 (** A trait instance id refers to a local clause if it only uses the variants:
     [Self], [Clause], [ParentClause], [ItemClause] *)
-let rec trait_instance_id_is_local_clause (id : 'r T.trait_instance_id) : bool =
+let rec trait_instance_id_is_local_clause (id : trait_instance_id) : bool =
   match id with
-  | T.Self | Clause _ -> true
+  | Self | Clause _ -> true
   | TraitImpl _ | BuiltinOrAuto _ | TraitRef _ | UnknownTrait _ | FnPointer _ ->
       false
   | ParentClause (id, _, _) | ItemClause (id, _, _, _) ->
@@ -165,104 +100,105 @@ let rec trait_instance_id_is_local_clause (id : 'r T.trait_instance_id) : bool =
 (** About the conversion functions: for now we need them (TODO: merge ety, rty, etc.),
     but they should be applied to types without regions.
  *)
-type 'r norm_ctx = {
-  ctx : C.eval_ctx;
-  get_ty_repr : 'r C.trait_type_ref -> 'r T.ty option;
-  convert_ety : T.ety -> 'r T.ty; (* TODO: remove? *)
-  convert_etrait_ref : T.etrait_ref -> 'r T.trait_ref; (* TODO: remove? *)
-  ty_to_string : 'r T.ty -> string;
-  generic_params_to_string : T.generic_params -> string;
-  generic_args_to_string : 'r T.generic_args -> string;
-  trait_ref_to_string : 'r T.trait_ref -> string;
-  trait_instance_id_to_string : 'r T.trait_instance_id -> string;
-  pp_r : Format.formatter -> 'r -> unit;
+type norm_ctx = {
+  norm_trait_types : ty TraitTypeRefMap.t;
+  type_decls : type_decl TypeDeclId.Map.t;
+  fun_decls : fun_decl FunDeclId.Map.t;
+  global_decls : global_decl GlobalDeclId.Map.t;
+  trait_decls : trait_decl TraitDeclId.Map.t;
+  trait_impls : trait_impl TraitImplId.Map.t;
+  type_vars : type_var list;
+  const_generic_vars : const_generic_var list;
 }
 
-(** Small utility to lookup trait impls, together with a substitution.
-
-    Remark: one reason we have those small helpers is that all functions are
-    parameterized by a type variable 'r. The OCaml type inferencer and type
-    checker are however not very good at generating precise error messages in
-    this context: if in the body of the function we have an overly constrained
-    usage of 'r (for instance, the type inferencer deduces 'r should be
-    [T.erased_region]), it will not be able to pinpoint the location which
-    introduced the constraints and we just get a type-checking error for the
-    whole function. The fact that we have mutually recursive functions makes it
-    worse (the type-checker sometimes indicates a well-typed function as not
-    well-typed, because it calls a not well-typed function...).
-    By isolating the places where such errors typically happen in small helpers
-    (i.e., the places where we convert between different types of regions by
-    performing substitutions), we make maintenance a lot easier.
- *)
-let ctx_lookup_trait_impl :
-      'r.
-      'r norm_ctx ->
-      T.TraitImplId.id ->
-      'r T.generic_args ->
-      A.trait_impl * (T.region_var_id T.region, 'r) Subst.subst =
- fun ctx impl_id generics ->
+let norm_ctx_to_fmt_env (ctx : norm_ctx) : Print.fmt_env =
+  {
+    type_decls = ctx.type_decls;
+    fun_decls = ctx.fun_decls;
+    global_decls = ctx.global_decls;
+    trait_decls = ctx.trait_decls;
+    trait_impls = ctx.trait_impls;
+    generics =
+      {
+        types = ctx.type_vars;
+        const_generics = ctx.const_generic_vars;
+        regions = [];
+        trait_clauses = [];
+      };
+    preds = empty_predicates;
+    locals = [];
+  }
+
+let norm_ctx_get_ty_repr (ctx : norm_ctx) (x : trait_type_ref) : ty option =
+  TraitTypeRefMap.find_opt x ctx.norm_trait_types
+
+let ty_to_string (ctx : norm_ctx) (ty : ty) : string =
+  let ctx = norm_ctx_to_fmt_env ctx in
+  Print.Types.ty_to_string ctx ty
+
+let trait_ref_to_string (ctx : norm_ctx) (x : trait_ref) : string =
+  let ctx = norm_ctx_to_fmt_env ctx in
+  Print.Types.trait_ref_to_string ctx x
+
+let trait_instance_id_to_string (ctx : norm_ctx) (x : trait_instance_id) :
+    string =
+  let ctx = norm_ctx_to_fmt_env ctx in
+  Print.Types.trait_instance_id_to_string ctx x
+
+let generic_args_to_string (ctx : norm_ctx) (x : generic_args) : string =
+  let ctx = norm_ctx_to_fmt_env ctx in
+  Print.Types.generic_args_to_string ctx x
+
+let generic_params_to_string (ctx : norm_ctx) (x : generic_params) : string =
+  let ctx = norm_ctx_to_fmt_env ctx in
+  "<"
+  ^ String.concat ", " (fst (Print.Types.generic_params_to_strings ctx x))
+  ^ ">"
+
+(** Small utility to lookup trait impls, together with a substitution. *)
+let norm_ctx_lookup_trait_impl (ctx : norm_ctx) (impl_id : TraitImplId.id)
+    (generics : generic_args) : trait_impl * Subst.subst =
   (* Lookup the implementation *)
-  let trait_impl = C.ctx_lookup_trait_impl ctx.ctx impl_id in
+  let trait_impl = TraitImplId.Map.find impl_id ctx.trait_impls in
   (* The substitution *)
-  let tr_self = T.UnknownTrait __FUNCTION__ in
+  let tr_self = UnknownTrait __FUNCTION__ in
   let subst =
-    Subst.make_subst_from_generics_no_regions trait_impl.generics generics
-      tr_self
+    Subst.make_subst_from_generics trait_impl.generics generics tr_self
   in
   (* Return *)
   (trait_impl, subst)
 
-let ctx_lookup_trait_impl_ty :
-      'r.
-      'r norm_ctx -> T.TraitImplId.id -> 'r T.generic_args -> string -> 'r T.ty
-    =
- fun ctx impl_id generics type_name ->
+let norm_ctx_lookup_trait_impl_ty (ctx : norm_ctx) (impl_id : TraitImplId.id)
+    (generics : generic_args) (type_name : string) : ty =
   (* Lookup the implementation *)
-  let trait_impl, subst = ctx_lookup_trait_impl ctx impl_id generics in
+  let trait_impl, subst = norm_ctx_lookup_trait_impl ctx impl_id generics in
   (* Lookup the type *)
   let ty = snd (List.assoc type_name trait_impl.types) in
-  (* Annoying: convert etype to an stype - TODO: how to avoid that? *)
-  let ty : T.sty = TypesUtils.ety_no_regions_to_gr_ty ty in
   (* Substitute *)
   Subst.ty_substitute subst ty
 
-let ctx_lookup_trait_impl_parent_clause :
-      'r.
-      'r norm_ctx ->
-      T.TraitImplId.id ->
-      'r T.generic_args ->
-      T.TraitClauseId.id ->
-      'r T.trait_ref =
- fun ctx impl_id generics clause_id ->
+let norm_ctx_lookup_trait_impl_parent_clause (ctx : norm_ctx)
+    (impl_id : TraitImplId.id) (generics : generic_args)
+    (clause_id : TraitClauseId.id) : trait_ref =
   (* Lookup the implementation *)
-  let trait_impl, subst = ctx_lookup_trait_impl ctx impl_id generics in
+  let trait_impl, subst = norm_ctx_lookup_trait_impl ctx impl_id generics in
   (* Lookup the clause *)
-  let clause = T.TraitClauseId.nth trait_impl.parent_trait_refs clause_id in
+  let clause = TraitClauseId.nth trait_impl.parent_trait_refs clause_id in
   (* Sanity check: the clause necessarily refers to an impl *)
   let _ = TypesUtils.trait_instance_id_as_trait_impl clause.trait_id in
   (* Substitute *)
   Subst.trait_ref_substitute subst clause
 
-let ctx_lookup_trait_impl_item_clause :
-      'r.
-      'r norm_ctx ->
-      T.TraitImplId.id ->
-      'r T.generic_args ->
-      string ->
-      T.TraitClauseId.id ->
-      'r T.trait_ref =
- fun ctx impl_id generics item_name clause_id ->
+let norm_ctx_lookup_trait_impl_item_clause (ctx : norm_ctx)
+    (impl_id : TraitImplId.id) (generics : generic_args) (item_name : string)
+    (clause_id : TraitClauseId.id) : trait_ref =
   (* Lookup the implementation *)
-  let trait_impl, subst = ctx_lookup_trait_impl ctx impl_id generics in
+  let trait_impl, subst = norm_ctx_lookup_trait_impl ctx impl_id generics in
   (* Lookup the item then its clause *)
   let item = List.assoc item_name trait_impl.types in
-  let clause = T.TraitClauseId.nth (fst item) clause_id in
+  let clause = TraitClauseId.nth (fst item) clause_id in
   (* Sanity check: the clause necessarily refers to an impl *)
   let _ = TypesUtils.trait_instance_id_as_trait_impl clause.trait_id in
-  (* Annoying: convert etype to an stype - TODO: how to avoid that? *)
-  let clause : T.strait_ref =
-    TypesUtils.etrait_ref_no_regions_to_gr_trait_ref clause
-  in
   (* Substitute *)
   Subst.trait_ref_substitute subst clause
 
@@ -270,89 +206,88 @@ let ctx_lookup_trait_impl_item_clause :
     and choosing a representative when there are equalities between types
     enforced by local clauses (i.e., `where Trait1::T = Trait2::U`.
 
-    See the comments for {!ctx_normalize_trait_instance_id}.
+    See the comments for {!norm_ctx_normalize_trait_instance_id}.
   *)
-let rec ctx_normalize_ty : 'r. 'r norm_ctx -> 'r T.ty -> 'r T.ty =
- fun ctx ty ->
-  log#ldebug (lazy ("ctx_normalize_ty: " ^ ctx.ty_to_string ty));
+let rec norm_ctx_normalize_ty (ctx : norm_ctx) (ty : ty) : ty =
+  log#ldebug (lazy ("norm_ctx_normalize_ty: " ^ ty_to_string ctx ty));
   match ty with
-  | T.Adt (id, generics) -> Adt (id, ctx_normalize_generic_args ctx generics)
-  | TypeVar _ | Literal _ | Never -> ty
-  | Ref (r, ty, rkind) ->
-      let ty = ctx_normalize_ty ctx ty in
-      T.Ref (r, ty, rkind)
-  | RawPtr (ty, rkind) ->
-      let ty = ctx_normalize_ty ctx ty in
-      RawPtr (ty, rkind)
-  | Arrow (inputs, output) ->
-      let inputs = List.map (ctx_normalize_ty ctx) inputs in
-      let output = ctx_normalize_ty ctx output in
-      Arrow (inputs, output)
-  | TraitType (trait_ref, generics, type_name) -> (
+  | TAdt (id, generics) ->
+      TAdt (id, norm_ctx_normalize_generic_args ctx generics)
+  | TVar _ | TLiteral _ | TNever -> ty
+  | TRef (r, ty, rkind) ->
+      let ty = norm_ctx_normalize_ty ctx ty in
+      TRef (r, ty, rkind)
+  | TRawPtr (ty, rkind) ->
+      let ty = norm_ctx_normalize_ty ctx ty in
+      TRawPtr (ty, rkind)
+  | TArrow (inputs, output) ->
+      let inputs = List.map (norm_ctx_normalize_ty ctx) inputs in
+      let output = norm_ctx_normalize_ty ctx output in
+      TArrow (inputs, output)
+  | TTraitType (trait_ref, generics, type_name) -> (
       log#ldebug
         (lazy
-          ("ctx_normalize_ty:\n- trait type: " ^ ctx.ty_to_string ty
+          ("norm_ctx_normalize_ty:\n- trait type: " ^ ty_to_string ctx ty
          ^ "\n- trait_ref: "
-          ^ ctx.trait_ref_to_string trait_ref
-          ^ "\n- raw trait ref:\n"
-          ^ T.show_trait_ref ctx.pp_r trait_ref
+          ^ trait_ref_to_string ctx trait_ref
+          ^ "\n- raw trait ref:\n" ^ show_trait_ref trait_ref
           ^ "\n- generics:\n"
-          ^ ctx.generic_args_to_string generics));
+          ^ generic_args_to_string ctx generics));
       (* Normalize and attempt to project the type from the trait ref *)
-      let trait_ref = ctx_normalize_trait_ref ctx trait_ref in
-      let generics = ctx_normalize_generic_args ctx generics in
+      let trait_ref = norm_ctx_normalize_trait_ref ctx trait_ref in
+      let generics = norm_ctx_normalize_generic_args ctx generics in
       (*  For now, we don't support higher order types *)
-      assert (generics = TypesUtils.mk_empty_generic_args);
-      let ty : 'r T.ty =
+      assert (generics = empty_generic_args);
+      let ty : ty =
         match trait_ref.trait_id with
-        | T.TraitRef
-            { T.trait_id = T.TraitImpl impl_id; generics = ref_generics; _ } ->
-            assert (ref_generics = TypesUtils.mk_empty_generic_args);
+        | TraitRef { trait_id = TraitImpl impl_id; generics = ref_generics; _ }
+          ->
+            assert (ref_generics = empty_generic_args);
             log#ldebug
               (lazy
-                ("ctx_normalize_ty: trait type: trait ref: "
-               ^ ctx.ty_to_string ty));
+                ("norm_ctx_normalize_ty: trait type: trait ref: "
+               ^ ty_to_string ctx ty));
             (* Lookup the type *)
             let ty =
-              ctx_lookup_trait_impl_ty ctx impl_id trait_ref.generics type_name
+              norm_ctx_lookup_trait_impl_ty ctx impl_id trait_ref.generics
+                type_name
             in
             (* Normalize *)
-            ctx_normalize_ty ctx ty
-        | T.TraitImpl impl_id ->
+            norm_ctx_normalize_ty ctx ty
+        | TraitImpl impl_id ->
             log#ldebug
               (lazy
-                ("ctx_normalize_ty (trait impl):\n- trait type: "
-               ^ ctx.ty_to_string ty ^ "\n- trait_ref: "
-                ^ ctx.trait_ref_to_string trait_ref
-                ^ "\n- raw trait ref:\n"
-                ^ T.show_trait_ref ctx.pp_r trait_ref));
+                ("norm_ctx_normalize_ty (trait impl):\n- trait type: "
+               ^ ty_to_string ctx ty ^ "\n- trait_ref: "
+                ^ trait_ref_to_string ctx trait_ref
+                ^ "\n- raw trait ref:\n" ^ show_trait_ref trait_ref));
             (* This happens. This doesn't come from the substitutions
                performed by Aeneas (the [TraitImpl] would be wrapped in a
                [TraitRef] but from non-normalized traits translated from
-               the Rustc AST.
+               the Rustc AS
                TODO: factor out with the branch above.
             *)
             (* Lookup the type *)
             let ty =
-              ctx_lookup_trait_impl_ty ctx impl_id trait_ref.generics type_name
+              norm_ctx_lookup_trait_impl_ty ctx impl_id trait_ref.generics
+                type_name
             in
             (* Normalize *)
-            ctx_normalize_ty ctx ty
+            norm_ctx_normalize_ty ctx ty
         | _ ->
             log#ldebug
               (lazy
-                ("ctx_normalize_ty: trait type: not a trait ref: "
-               ^ ctx.ty_to_string ty ^ "\n- trait_ref: "
-                ^ ctx.trait_ref_to_string trait_ref
-                ^ "\n- raw trait ref:\n"
-                ^ T.show_trait_ref ctx.pp_r trait_ref));
+                ("norm_ctx_normalize_ty: trait type: not a trait ref: "
+               ^ ty_to_string ctx ty ^ "\n- trait_ref: "
+                ^ trait_ref_to_string ctx trait_ref
+                ^ "\n- raw trait ref:\n" ^ show_trait_ref trait_ref));
             (* We can't project *)
             assert (trait_instance_id_is_local_clause trait_ref.trait_id);
-            T.TraitType (trait_ref, generics, type_name)
+            TTraitType (trait_ref, generics, type_name)
       in
-      let tr : 'r C.trait_type_ref = { C.trait_ref; type_name } in
+      let tr : trait_type_ref = { trait_ref; type_name } in
       (* Lookup the representative, if there is *)
-      match ctx.get_ty_repr tr with None -> ty | Some ty -> ty)
+      match norm_ctx_get_ty_repr ctx tr with None -> ty | Some ty -> ty)
 
 (** This returns the normalized trait instance id together with an optional
     reference to a trait **implementation** (the `trait_ref` we return has
@@ -398,12 +333,8 @@ let rec ctx_normalize_ty : 'r. 'r norm_ctx -> 'r T.ty -> 'r T.ty =
         In this case we can lookup the trait implementation and recursively project
         over it.
  *)
-and ctx_normalize_trait_instance_id :
-      'r.
-      'r norm_ctx ->
-      'r T.trait_instance_id ->
-      'r T.trait_instance_id * 'r T.trait_ref option =
- fun ctx id ->
+and norm_ctx_normalize_trait_instance_id (ctx : norm_ctx)
+    (id : trait_instance_id) : trait_instance_id * trait_ref option =
   match id with
   | Self -> (id, None)
   | TraitImpl _ ->
@@ -414,7 +345,7 @@ and ctx_normalize_trait_instance_id :
   | Clause _ -> (id, None)
   | BuiltinOrAuto _ -> (id, None)
   | ParentClause (inst_id, decl_id, clause_id) -> (
-      let inst_id, impl = ctx_normalize_trait_instance_id ctx inst_id in
+      let inst_id, impl = norm_ctx_normalize_trait_instance_id ctx inst_id in
       (* Check if the inst_id refers to a specific implementation, if yes project *)
       match impl with
       | None ->
@@ -438,14 +369,14 @@ and ctx_normalize_trait_instance_id :
             TypesUtils.trait_instance_id_as_trait_impl impl.trait_id
           in
           let clause =
-            ctx_lookup_trait_impl_parent_clause ctx impl_id impl.generics
+            norm_ctx_lookup_trait_impl_parent_clause ctx impl_id impl.generics
               clause_id
           in
           (* Normalize the clause *)
-          let clause = ctx_normalize_trait_ref ctx clause in
+          let clause = norm_ctx_normalize_trait_ref ctx clause in
           (TraitRef clause, Some clause))
   | ItemClause (inst_id, decl_id, item_name, clause_id) -> (
-      let inst_id, impl = ctx_normalize_trait_instance_id ctx inst_id in
+      let inst_id, impl = norm_ctx_normalize_trait_instance_id ctx inst_id in
       (* Check if the inst_id refers to a specific implementation, if yes project *)
       match impl with
       | None ->
@@ -469,30 +400,32 @@ and ctx_normalize_trait_instance_id :
             TypesUtils.trait_instance_id_as_trait_impl impl.trait_id
           in
           let clause =
-            ctx_lookup_trait_impl_item_clause ctx impl_id impl.generics
+            norm_ctx_lookup_trait_impl_item_clause ctx impl_id impl.generics
               item_name clause_id
           in
           (* Normalize the clause *)
-          let clause = ctx_normalize_trait_ref ctx clause in
+          let clause = norm_ctx_normalize_trait_ref ctx clause in
           (TraitRef clause, Some clause))
-  | TraitRef { T.trait_id = T.TraitImpl trait_id; generics; trait_decl_ref } ->
+  | TraitRef { trait_id = TraitImpl trait_id; generics; trait_decl_ref } ->
       (* We can't simplify the id *yet* : we will simplify it when projecting.
          However, we have an implementation to return *)
       (* Normalize the generics *)
-      let generics = ctx_normalize_generic_args ctx generics in
-      let trait_decl_ref = ctx_normalize_trait_decl_ref ctx trait_decl_ref in
-      let trait_ref : 'r T.trait_ref =
-        { T.trait_id = T.TraitImpl trait_id; generics; trait_decl_ref }
+      let generics = norm_ctx_normalize_generic_args ctx generics in
+      let trait_decl_ref =
+        norm_ctx_normalize_trait_decl_ref ctx trait_decl_ref
+      in
+      let trait_ref : trait_ref =
+        { trait_id = TraitImpl trait_id; generics; trait_decl_ref }
       in
       (TraitRef trait_ref, Some trait_ref)
   | TraitRef trait_ref ->
       (* The trait instance id necessarily refers to a local sub-clause. We
          can't project over it and can only peel off the [TraitRef] wrapper *)
       assert (trait_instance_id_is_local_clause trait_ref.trait_id);
-      assert (trait_ref.generics = TypesUtils.mk_empty_generic_args);
+      assert (trait_ref.generics = empty_generic_args);
       (trait_ref.trait_id, None)
   | FnPointer ty ->
-      let ty = ctx_normalize_ty ctx ty in
+      let ty = norm_ctx_normalize_ty ctx ty in
       (* TODO: we might want to return the ref to the function pointer,
          in order to later normalize a call to this function pointer *)
       (FnPointer ty, None)
@@ -500,182 +433,148 @@ and ctx_normalize_trait_instance_id :
       (* This is actually an error case *)
       (id, None)
 
-and ctx_normalize_generic_args (ctx : 'r norm_ctx)
-    (generics : 'r T.generic_args) : 'r T.generic_args =
-  let { T.regions; types; const_generics; trait_refs } = generics in
-  let types = List.map (ctx_normalize_ty ctx) types in
-  let trait_refs = List.map (ctx_normalize_trait_ref ctx) trait_refs in
-  { T.regions; types; const_generics; trait_refs }
+and norm_ctx_normalize_generic_args (ctx : norm_ctx) (generics : generic_args) :
+    generic_args =
+  let { regions; types; const_generics; trait_refs } = generics in
+  let types = List.map (norm_ctx_normalize_ty ctx) types in
+  let trait_refs = List.map (norm_ctx_normalize_trait_ref ctx) trait_refs in
+  { regions; types; const_generics; trait_refs }
 
-and ctx_normalize_trait_ref (ctx : 'r norm_ctx) (trait_ref : 'r T.trait_ref) :
-    'r T.trait_ref =
+and norm_ctx_normalize_trait_ref (ctx : norm_ctx) (trait_ref : trait_ref) :
+    trait_ref =
   log#ldebug
     (lazy
-      ("ctx_normalize_trait_ref: "
-      ^ ctx.trait_ref_to_string trait_ref
-      ^ "\n- raw trait ref:\n"
-      ^ T.show_trait_ref ctx.pp_r trait_ref));
-  let { T.trait_id; generics; trait_decl_ref } = trait_ref in
+      ("norm_ctx_normalize_trait_ref: "
+      ^ trait_ref_to_string ctx trait_ref
+      ^ "\n- raw trait ref:\n" ^ show_trait_ref trait_ref));
+  let { trait_id; generics; trait_decl_ref } = trait_ref in
   (* Check if the id is an impl, otherwise normalize it *)
-  let trait_id, norm_trait_ref = ctx_normalize_trait_instance_id ctx trait_id in
+  let trait_id, norm_trait_ref =
+    norm_ctx_normalize_trait_instance_id ctx trait_id
+  in
   match norm_trait_ref with
   | None ->
       log#ldebug
         (lazy
-          ("ctx_normalize_trait_ref: no norm: "
-          ^ ctx.trait_instance_id_to_string trait_id));
-      let generics = ctx_normalize_generic_args ctx generics in
-      let trait_decl_ref = ctx_normalize_trait_decl_ref ctx trait_decl_ref in
-      { T.trait_id; generics; trait_decl_ref }
+          ("norm_ctx_normalize_trait_ref: no norm: "
+          ^ trait_instance_id_to_string ctx trait_id));
+      let generics = norm_ctx_normalize_generic_args ctx generics in
+      let trait_decl_ref =
+        norm_ctx_normalize_trait_decl_ref ctx trait_decl_ref
+      in
+      { trait_id; generics; trait_decl_ref }
   | Some trait_ref ->
       log#ldebug
         (lazy
-          ("ctx_normalize_trait_ref: normalized to: "
-          ^ ctx.trait_ref_to_string trait_ref));
-      assert (generics = TypesUtils.mk_empty_generic_args);
+          ("norm_ctx_normalize_trait_ref: normalized to: "
+          ^ trait_ref_to_string ctx trait_ref));
+      assert (generics = empty_generic_args);
       trait_ref
 
 (* Not sure this one is really necessary *)
-and ctx_normalize_trait_decl_ref (ctx : 'r norm_ctx)
-    (trait_decl_ref : 'r T.trait_decl_ref) : 'r T.trait_decl_ref =
-  let { T.trait_decl_id; decl_generics } = trait_decl_ref in
-  let decl_generics = ctx_normalize_generic_args ctx decl_generics in
-  { T.trait_decl_id; decl_generics }
-
-let ctx_normalize_trait_type_constraint (ctx : 'r norm_ctx)
-    (ttc : 'r T.trait_type_constraint) : 'r T.trait_type_constraint =
-  let { T.trait_ref; generics; type_name; ty } = ttc in
-  let trait_ref = ctx_normalize_trait_ref ctx trait_ref in
-  let generics = ctx_normalize_generic_args ctx generics in
-  let ty = ctx_normalize_ty ctx ty in
-  { T.trait_ref; generics; type_name; ty }
-
-let generic_params_to_string ctx x =
-  "<" ^ String.concat ", " (fst (PA.generic_params_to_strings ctx x)) ^ ">"
-
-let mk_snorm_ctx (ctx : C.eval_ctx) : T.RegionVarId.id T.region norm_ctx =
-  let get_ty_repr x = C.STraitTypeRefMap.find_opt x ctx.norm_trait_stypes in
+and norm_ctx_normalize_trait_decl_ref (ctx : norm_ctx)
+    (trait_decl_ref : trait_decl_ref) : trait_decl_ref =
+  let { trait_decl_id; decl_generics } = trait_decl_ref in
+  let decl_generics = norm_ctx_normalize_generic_args ctx decl_generics in
+  { trait_decl_id; decl_generics }
+
+let norm_ctx_normalize_trait_type_constraint (ctx : norm_ctx)
+    (ttc : trait_type_constraint) : trait_type_constraint =
+  let { trait_ref; generics; type_name; ty } = ttc in
+  let trait_ref = norm_ctx_normalize_trait_ref ctx trait_ref in
+  let generics = norm_ctx_normalize_generic_args ctx generics in
+  let ty = norm_ctx_normalize_ty ctx ty in
+  { trait_ref; generics; type_name; ty }
+
+let mk_norm_ctx (ctx : eval_ctx) : norm_ctx =
   {
-    ctx;
-    get_ty_repr;
-    convert_ety = TypesUtils.ety_no_regions_to_sty;
-    convert_etrait_ref = TypesUtils.etrait_ref_no_regions_to_gr_trait_ref;
-    ty_to_string = PA.sty_to_string ctx;
-    generic_params_to_string = generic_params_to_string ctx;
-    generic_args_to_string = PA.sgeneric_args_to_string ctx;
-    trait_ref_to_string = PA.strait_ref_to_string ctx;
-    trait_instance_id_to_string = PA.strait_instance_id_to_string ctx;
-    pp_r = T.pp_region T.pp_region_var_id;
+    norm_trait_types = ctx.norm_trait_types;
+    type_decls = ctx.type_context.type_decls;
+    fun_decls = ctx.fun_context.fun_decls;
+    global_decls = ctx.global_context.global_decls;
+    trait_decls = ctx.trait_decls_context.trait_decls;
+    trait_impls = ctx.trait_impls_context.trait_impls;
+    type_vars = ctx.type_vars;
+    const_generic_vars = ctx.const_generic_vars;
   }
 
-let mk_rnorm_ctx (ctx : C.eval_ctx) : T.RegionId.id T.region norm_ctx =
-  let get_ty_repr x = C.RTraitTypeRefMap.find_opt x ctx.norm_trait_rtypes in
-  {
-    ctx;
-    get_ty_repr;
-    convert_ety = TypesUtils.ety_no_regions_to_rty;
-    convert_etrait_ref = TypesUtils.etrait_ref_no_regions_to_gr_trait_ref;
-    ty_to_string = PA.rty_to_string ctx;
-    generic_params_to_string = generic_params_to_string ctx;
-    generic_args_to_string = PA.rgeneric_args_to_string ctx;
-    trait_ref_to_string = PA.rtrait_ref_to_string ctx;
-    trait_instance_id_to_string = PA.rtrait_instance_id_to_string ctx;
-    pp_r = T.pp_region T.pp_region_id;
-  }
-
-let mk_enorm_ctx (ctx : C.eval_ctx) : T.erased_region norm_ctx =
-  let get_ty_repr x = C.ETraitTypeRefMap.find_opt x ctx.norm_trait_etypes in
-  {
-    ctx;
-    get_ty_repr;
-    convert_ety = (fun x -> x);
-    convert_etrait_ref = (fun x -> x);
-    ty_to_string = PA.ety_to_string ctx;
-    generic_params_to_string = generic_params_to_string ctx;
-    generic_args_to_string = PA.egeneric_args_to_string ctx;
-    trait_ref_to_string = PA.etrait_ref_to_string ctx;
-    trait_instance_id_to_string = PA.etrait_instance_id_to_string ctx;
-    pp_r = T.pp_erased_region;
-  }
+let ctx_normalize_ty (ctx : eval_ctx) (ty : ty) : ty =
+  norm_ctx_normalize_ty (mk_norm_ctx ctx) ty
 
-let ctx_normalize_sty (ctx : C.eval_ctx) (ty : T.sty) : T.sty =
-  ctx_normalize_ty (mk_snorm_ctx ctx) ty
-
-let ctx_normalize_rty (ctx : C.eval_ctx) (ty : T.rty) : T.rty =
-  ctx_normalize_ty (mk_rnorm_ctx ctx) ty
-
-let ctx_normalize_ety (ctx : C.eval_ctx) (ty : T.ety) : T.ety =
-  ctx_normalize_ty (mk_enorm_ctx ctx) ty
+(** Normalize a type and erase the regions at the same time *)
+let ctx_normalize_erase_ty (ctx : eval_ctx) (ty : ty) : ty =
+  let ty = ctx_normalize_ty ctx ty in
+  Subst.erase_regions ty
 
-let ctx_normalize_rtrait_type_constraint (ctx : C.eval_ctx)
-    (ttc : T.rtrait_type_constraint) : T.rtrait_type_constraint =
-  ctx_normalize_trait_type_constraint (mk_rnorm_ctx ctx) ttc
+let ctx_normalize_trait_type_constraint (ctx : eval_ctx)
+    (ttc : trait_type_constraint) : trait_type_constraint =
+  norm_ctx_normalize_trait_type_constraint (mk_norm_ctx ctx) ttc
 
-(** Same as [type_decl_get_instantiated_variants_fields_rtypes] but normalizes the types *)
-let type_decl_get_inst_norm_variants_fields_rtypes (ctx : C.eval_ctx)
-    (def : T.type_decl) (generics : T.rgeneric_args) :
-    (T.VariantId.id option * T.rty list) list =
+(** Same as [type_decl_get_instantiated_variants_fields_types] but normalizes the types *)
+let type_decl_get_inst_norm_variants_fields_rtypes (ctx : eval_ctx)
+    (def : type_decl) (generics : generic_args) :
+    (VariantId.id option * ty list) list =
   let res =
-    Subst.type_decl_get_instantiated_variants_fields_rtypes def generics
+    Subst.type_decl_get_instantiated_variants_fields_types def generics
   in
   List.map
     (fun (variant_id, types) ->
-      (variant_id, List.map (ctx_normalize_rty ctx) types))
+      (variant_id, List.map (ctx_normalize_ty ctx) types))
     res
 
-(** Same as [type_decl_get_instantiated_field_rtypes] but normalizes the types *)
-let type_decl_get_inst_norm_field_rtypes (ctx : C.eval_ctx) (def : T.type_decl)
-    (opt_variant_id : T.VariantId.id option) (generics : T.rgeneric_args) :
-    T.rty list =
+(** Same as [type_decl_get_instantiated_field_types] but normalizes the types *)
+let type_decl_get_inst_norm_field_rtypes (ctx : eval_ctx) (def : type_decl)
+    (opt_variant_id : VariantId.id option) (generics : generic_args) : ty list =
   let types =
-    Subst.type_decl_get_instantiated_field_rtypes def opt_variant_id generics
+    Subst.type_decl_get_instantiated_field_types def opt_variant_id generics
   in
-  List.map (ctx_normalize_rty ctx) types
+  List.map (ctx_normalize_ty ctx) types
 
 (** Same as [ctx_adt_value_get_instantiated_field_rtypes] but normalizes the types *)
-let ctx_adt_value_get_inst_norm_field_rtypes (ctx : C.eval_ctx)
-    (adt : V.adt_value) (id : T.type_id) (generics : T.rgeneric_args) :
-    T.rty list =
+let ctx_adt_value_get_inst_norm_field_rtypes (ctx : eval_ctx) (adt : adt_value)
+    (id : type_id) (generics : generic_args) : ty list =
   let types =
-    Subst.ctx_adt_value_get_instantiated_field_rtypes ctx adt id generics
+    Subst.ctx_adt_value_get_instantiated_field_types ctx adt id generics
   in
-  List.map (ctx_normalize_rty ctx) types
+  List.map (ctx_normalize_ty ctx) types
 
-(** Same as [ctx_adt_value_get_instantiated_field_etypes] but normalizes the types *)
-let type_decl_get_inst_norm_field_etypes (ctx : C.eval_ctx) (def : T.type_decl)
-    (opt_variant_id : T.VariantId.id option) (generics : T.egeneric_args) :
-    T.ety list =
+(** Same as [ctx_adt_value_get_instantiated_field_types] but normalizes the types
+    and erases the regions. *)
+let type_decl_get_inst_norm_field_etypes (ctx : eval_ctx) (def : type_decl)
+    (opt_variant_id : VariantId.id option) (generics : generic_args) : ty list =
   let types =
-    Subst.type_decl_get_instantiated_field_etypes def opt_variant_id generics
+    Subst.type_decl_get_instantiated_field_types def opt_variant_id generics
   in
-  List.map (ctx_normalize_ety ctx) types
+  let types = List.map (ctx_normalize_ty ctx) types in
+  List.map Subst.erase_regions types
 
-(** Same as [ctx_adt_get_instantiated_field_etypes] but normalizes the types *)
-let ctx_adt_get_inst_norm_field_etypes (ctx : C.eval_ctx)
-    (def_id : T.TypeDeclId.id) (opt_variant_id : T.VariantId.id option)
-    (generics : T.egeneric_args) : T.ety list =
+(** Same as [ctx_adt_get_instantiated_field_types] but normalizes the types and
+    erases the regions. *)
+let ctx_adt_get_inst_norm_field_etypes (ctx : eval_ctx) (def_id : TypeDeclId.id)
+    (opt_variant_id : VariantId.id option) (generics : generic_args) : ty list =
   let types =
-    Subst.ctx_adt_get_instantiated_field_etypes ctx def_id opt_variant_id
+    Subst.ctx_adt_get_instantiated_field_types ctx def_id opt_variant_id
       generics
   in
-  List.map (ctx_normalize_ety ctx) types
+  let types = List.map (ctx_normalize_ty ctx) types in
+  List.map Subst.erase_regions types
 
 (** Same as [substitute_signature] but normalizes the types *)
-let ctx_subst_norm_signature (ctx : C.eval_ctx)
-    (asubst : T.RegionGroupId.id -> V.AbstractionId.id)
-    (r_subst : T.RegionVarId.id -> T.RegionId.id)
-    (ty_subst : T.TypeVarId.id -> T.rty)
-    (cg_subst : T.ConstGenericVarId.id -> T.const_generic)
-    (tr_subst : T.TraitClauseId.id -> T.rtrait_instance_id)
-    (tr_self : T.rtrait_instance_id) (sg : A.fun_sig) : A.inst_fun_sig =
+let ctx_subst_norm_signature (ctx : eval_ctx)
+    (asubst : RegionGroupId.id -> AbstractionId.id)
+    (r_subst : RegionId.id -> RegionId.id) (ty_subst : TypeVarId.id -> ty)
+    (cg_subst : ConstGenericVarId.id -> const_generic)
+    (tr_subst : TraitClauseId.id -> trait_instance_id)
+    (tr_self : trait_instance_id) (sg : fun_sig)
+    (regions_hierarchy : region_groups) : inst_fun_sig =
   let sg =
     Subst.substitute_signature asubst r_subst ty_subst cg_subst tr_subst tr_self
-      sg
+      sg regions_hierarchy
   in
-  let { A.regions_hierarchy; inputs; output; trait_type_constraints } = sg in
-  let inputs = List.map (ctx_normalize_rty ctx) inputs in
-  let output = ctx_normalize_rty ctx output in
+  let { regions_hierarchy; inputs; output; trait_type_constraints } = sg in
+  let inputs = List.map (ctx_normalize_ty ctx) inputs in
+  let output = ctx_normalize_ty ctx output in
   let trait_type_constraints =
-    List.map (ctx_normalize_rtrait_type_constraint ctx) trait_type_constraints
+    List.map (ctx_normalize_trait_type_constraint ctx) trait_type_constraints
   in
   { regions_hierarchy; inputs; output; trait_type_constraints }
diff --git a/compiler/Assumed.ml b/compiler/Assumed.ml
index 79f6b0d4..48b7ee2b 100644
--- a/compiler/Assumed.ml
+++ b/compiler/Assumed.ml
@@ -29,59 +29,57 @@
     ]}
  *)
 
-open Names
+open Types
 open TypesUtils
-module T = Types
-module A = LlbcAst
+open LlbcAst
 
 module Sig = struct
   (** A few utilities *)
 
-  let rvar_id_0 = T.RegionVarId.of_int 0
-  let rvar_0 : T.RegionVarId.id T.region = T.Var rvar_id_0
-  let rg_id_0 = T.RegionGroupId.of_int 0
-  let tvar_id_0 = T.TypeVarId.of_int 0
-  let tvar_0 : T.sty = T.TypeVar tvar_id_0
-  let cgvar_id_0 = T.ConstGenericVarId.of_int 0
-  let cgvar_0 : T.const_generic = T.ConstGenericVar cgvar_id_0
+  let rvar_id_0 = RegionId.of_int 0
+  let rvar_0 : region = RVar rvar_id_0
+  let rg_id_0 = RegionGroupId.of_int 0
+  let tvar_id_0 = TypeVarId.of_int 0
+  let tvar_0 : ty = TVar tvar_id_0
+  let cgvar_id_0 = ConstGenericVarId.of_int 0
+  let cgvar_0 : const_generic = CgVar cgvar_id_0
 
   (** Region 'a of id 0 *)
-  let region_param_0 : T.region_var = { T.index = rvar_id_0; name = Some "'a" }
+  let region_param_0 : region_var = { index = rvar_id_0; name = Some "'a" }
 
   (** Region group: [{ parent={}; regions:{'a of id 0} }] *)
-  let region_group_0 : T.region_var_group =
-    { T.id = rg_id_0; regions = [ rvar_id_0 ]; parents = [] }
+  let region_group_0 : region_group =
+    { id = rg_id_0; regions = [ rvar_id_0 ]; parents = [] }
 
   (** Type parameter [T] of id 0 *)
-  let type_param_0 : T.type_var = { T.index = tvar_id_0; name = "T" }
+  let type_param_0 : type_var = { index = tvar_id_0; name = "T" }
 
-  let usize_ty : T.sty = T.Literal (Integer Usize)
+  let usize_ty : ty = TLiteral (TInteger Usize)
 
   (** Const generic parameter [const N : usize] of id 0 *)
-  let cg_param_0 : T.const_generic_var =
-    { T.index = cgvar_id_0; name = "N"; ty = Integer Usize }
+  let cg_param_0 : const_generic_var =
+    { index = cgvar_id_0; name = "N"; ty = TInteger Usize }
 
-  let empty_const_generic_params : T.const_generic_var list = []
+  let empty_const_generic_params : const_generic_var list = []
 
-  let mk_generic_args regions types const_generics : T.sgeneric_args =
+  let mk_generic_args regions types const_generics : generic_args =
     { regions; types; const_generics; trait_refs = [] }
 
-  let mk_generic_params regions types const_generics : T.generic_params =
+  let mk_generic_params regions types const_generics : generic_params =
     { regions; types; const_generics; trait_clauses = [] }
 
-  let mk_ref_ty (r : T.RegionVarId.id T.region) (ty : T.sty) (is_mut : bool) :
-      T.sty =
-    let ref_kind = if is_mut then T.Mut else T.Shared in
+  let mk_ref_ty (r : region) (ty : ty) (is_mut : bool) : ty =
+    let ref_kind = if is_mut then RMut else RShared in
     mk_ref_ty r ty ref_kind
 
-  let mk_array_ty (ty : T.sty) (cg : T.const_generic) : T.sty =
-    Adt (Assumed Array, mk_generic_args [] [ ty ] [ cg ])
+  let mk_array_ty (ty : ty) (cg : const_generic) : ty =
+    TAdt (TAssumed TArray, mk_generic_args [] [ ty ] [ cg ])
 
-  let mk_slice_ty (ty : T.sty) : T.sty =
-    Adt (Assumed Slice, mk_generic_args [] [ ty ] [])
+  let mk_slice_ty (ty : ty) : ty =
+    TAdt (TAssumed TSlice, mk_generic_args [] [ ty ] [])
 
-  let mk_sig generics regions_hierarchy inputs output : A.fun_sig =
-    let preds : T.predicates =
+  let mk_sig generics inputs output : fun_sig =
+    let preds : predicates =
       { regions_outlive = []; types_outlive = []; trait_type_constraints = [] }
     in
     {
@@ -89,26 +87,23 @@ module Sig = struct
       generics;
       preds;
       parent_params_info = None;
-      regions_hierarchy;
       inputs;
       output;
     }
 
   (** [fn<T>(T) -> Box<T>] *)
-  let box_new_sig : A.fun_sig =
+  let box_new_sig : fun_sig =
     let generics = mk_generic_params [] [ type_param_0 ] [] (* <T> *) in
-    let regions_hierarchy = [] in
     let inputs = [ tvar_0 (* T *) ] in
     let output = mk_box_ty tvar_0 (* Box<T> *) in
-    mk_sig generics regions_hierarchy inputs output
+    mk_sig generics inputs output
 
   (** [fn<T>(Box<T>) -> ()] *)
-  let box_free_sig : A.fun_sig =
+  let box_free_sig : fun_sig =
     let generics = mk_generic_params [] [ type_param_0 ] [] (* <T> *) in
-    let regions_hierarchy = [] in
     let inputs = [ mk_box_ty tvar_0 (* Box<T> *) ] in
     let output = mk_unit_ty (* () *) in
-    mk_sig generics regions_hierarchy inputs output
+    mk_sig generics inputs output
 
   (** Array/slice functions *)
 
@@ -124,13 +119,12 @@ module Sig = struct
       The [mut_borrow] boolean controls whether we use a shared or a mutable
       borrow.
    *)
-  let mk_array_slice_borrow_sig (cgs : T.const_generic_var list)
-      (input_ty : T.TypeVarId.id -> T.sty) (index_ty : T.sty option)
-      (output_ty : T.TypeVarId.id -> T.sty) (is_mut : bool) : A.fun_sig =
+  let mk_array_slice_borrow_sig (cgs : const_generic_var list)
+      (input_ty : TypeVarId.id -> ty) (index_ty : ty option)
+      (output_ty : TypeVarId.id -> ty) (is_mut : bool) : fun_sig =
     let generics =
       mk_generic_params [ region_param_0 ] [ type_param_0 ] cgs (* <'a, T> *)
     in
-    let regions_hierarchy = [ region_group_0 ] (* <'a> *) in
     let inputs =
       [
         mk_ref_ty rvar_0
@@ -146,29 +140,28 @@ module Sig = struct
         (output_ty type_param_0.index)
         is_mut (* &'a (mut) output_ty<T> *)
     in
-    mk_sig generics regions_hierarchy inputs output
+    mk_sig generics inputs output
 
-  let mk_array_slice_index_sig (is_array : bool) (is_mut : bool) : A.fun_sig =
+  let mk_array_slice_index_sig (is_array : bool) (is_mut : bool) : fun_sig =
     (* Array<T, N> *)
     let input_ty id =
-      if is_array then mk_array_ty (T.TypeVar id) cgvar_0
-      else mk_slice_ty (T.TypeVar id)
+      if is_array then mk_array_ty (TVar id) cgvar_0 else mk_slice_ty (TVar id)
     in
     (* usize *)
     let index_ty = usize_ty in
     (* T *)
-    let output_ty id = T.TypeVar id in
+    let output_ty id = TVar id in
     let cgs = if is_array then [ cg_param_0 ] else [] in
     mk_array_slice_borrow_sig cgs input_ty (Some index_ty) output_ty is_mut
 
   let array_index_sig (is_mut : bool) = mk_array_slice_index_sig true is_mut
   let slice_index_sig (is_mut : bool) = mk_array_slice_index_sig false is_mut
 
-  let array_to_slice_sig (is_mut : bool) : A.fun_sig =
+  let array_to_slice_sig (is_mut : bool) : fun_sig =
     (* Array<T, N> *)
-    let input_ty id = mk_array_ty (T.TypeVar id) cgvar_0 in
+    let input_ty id = mk_array_ty (TVar id) cgvar_0 in
     (* Slice<T> *)
-    let output_ty id = mk_slice_ty (T.TypeVar id) in
+    let output_ty id = mk_slice_ty (TVar id) in
     let cgs = [ cg_param_0 ] in
     mk_array_slice_borrow_sig cgs input_ty None output_ty is_mut
 
@@ -177,37 +170,35 @@ module Sig = struct
       (* <T, N> *)
       mk_generic_params [] [ type_param_0 ] [ cg_param_0 ]
     in
-    let regions_hierarchy = [] (* <> *) in
     let inputs = [ tvar_0 (* T *) ] in
     let output =
       (* [T; N] *)
       mk_array_ty tvar_0 cgvar_0
     in
-    mk_sig generics regions_hierarchy inputs output
+    mk_sig generics inputs output
 
   (** Helper:
       [fn<T>(&'a [T]) -> usize]
    *)
-  let slice_len_sig : A.fun_sig =
+  let slice_len_sig : fun_sig =
     let generics =
       mk_generic_params [ region_param_0 ] [ type_param_0 ] [] (* <'a, T> *)
     in
-    let regions_hierarchy = [ region_group_0 ] (* <'a> *) in
     let inputs =
       [ mk_ref_ty rvar_0 (mk_slice_ty tvar_0) false (* &'a [T] *) ]
     in
     let output = mk_usize_ty (* usize *) in
-    mk_sig generics regions_hierarchy inputs output
+    mk_sig generics inputs output
 end
 
 type raw_assumed_fun_info =
-  A.assumed_fun_id * A.fun_sig * bool * name * bool list option
+  assumed_fun_id * fun_sig * bool * string * bool list option
 
 type assumed_fun_info = {
-  fun_id : A.assumed_fun_id;
-  fun_sig : A.fun_sig;
+  fun_id : assumed_fun_id;
+  fun_sig : fun_sig;
   can_fail : bool;
-  name : name;
+  name : string;
   keep_types : bool list option;
       (** We may want to filter some type arguments.
 
@@ -233,70 +224,63 @@ let mk_assumed_fun_info (raw : raw_assumed_fun_info) : assumed_fun_info =
  *)
 let raw_assumed_fun_infos : raw_assumed_fun_info list =
   [
+    (* TODO: the names are not correct ("Box" should be an impl elem for instance)
+       but it's not important) *)
     ( BoxNew,
       Sig.box_new_sig,
       false,
-      to_name [ "alloc"; "boxed"; "Box"; "new" ],
+      "alloc::boxed::Box::new",
       Some [ true; false ] );
     (* BoxFree shouldn't be used *)
     ( BoxFree,
       Sig.box_free_sig,
       false,
-      to_name [ "alloc"; "boxed"; "Box"; "free" ],
+      "alloc::boxed::Box::free",
       Some [ true; false ] );
     (* Array Index *)
     ( ArrayIndexShared,
       Sig.array_index_sig false,
       true,
-      to_name [ "@ArrayIndexShared" ],
-      None );
-    ( ArrayIndexMut,
-      Sig.array_index_sig true,
-      true,
-      to_name [ "@ArrayIndexMut" ],
+      "@ArrayIndexShared",
       None );
+    (ArrayIndexMut, Sig.array_index_sig true, true, "@ArrayIndexMut", None);
     (* Array to slice*)
     ( ArrayToSliceShared,
       Sig.array_to_slice_sig false,
       true,
-      to_name [ "@ArrayToSliceShared" ],
+      "@ArrayToSliceShared",
       None );
     ( ArrayToSliceMut,
       Sig.array_to_slice_sig true,
       true,
-      to_name [ "@ArrayToSliceMut" ],
+      "@ArrayToSliceMut",
       None );
     (* Array Repeat *)
-    (ArrayRepeat, Sig.array_repeat_sig, false, to_name [ "@ArrayRepeat" ], None);
+    (ArrayRepeat, Sig.array_repeat_sig, false, "@ArrayRepeat", None);
     (* Slice Index *)
     ( SliceIndexShared,
       Sig.slice_index_sig false,
       true,
-      to_name [ "@SliceIndexShared" ],
-      None );
-    ( SliceIndexMut,
-      Sig.slice_index_sig true,
-      true,
-      to_name [ "@SliceIndexMut" ],
+      "@SliceIndexShared",
       None );
-    (SliceLen, Sig.slice_len_sig, false, to_name [ "@SliceLen" ], None);
+    (SliceIndexMut, Sig.slice_index_sig true, true, "@SliceIndexMut", None);
   ]
 
 let assumed_fun_infos : assumed_fun_info list =
   List.map mk_assumed_fun_info raw_assumed_fun_infos
 
-let get_assumed_fun_info (id : A.assumed_fun_id) : assumed_fun_info =
+let get_assumed_fun_info (id : assumed_fun_id) : assumed_fun_info =
   match List.find_opt (fun x -> id = x.fun_id) assumed_fun_infos with
   | Some info -> info
   | None ->
       raise
-        (Failure ("get_assumed_fun_info: not found: " ^ A.show_assumed_fun_id id))
+        (Failure ("get_assumed_fun_info: not found: " ^ show_assumed_fun_id id))
 
-let get_assumed_fun_sig (id : A.assumed_fun_id) : A.fun_sig =
+let get_assumed_fun_sig (id : assumed_fun_id) : fun_sig =
   (get_assumed_fun_info id).fun_sig
 
-let get_assumed_fun_name (id : A.assumed_fun_id) : fun_name =
+let get_assumed_fun_name (id : assumed_fun_id) : string =
   (get_assumed_fun_info id).name
 
-let assumed_fun_can_fail (id : A.assumed_fun_id) : bool =
+let assumed_fun_can_fail (id : assumed_fun_id) : bool =
   (get_assumed_fun_info id).can_fail
diff --git a/compiler/Config.ml b/compiler/Config.ml
index a487f9e2..fe110ee4 100644
--- a/compiler/Config.ml
+++ b/compiler/Config.ml
@@ -336,3 +336,30 @@ let type_check_pure_code = ref false
 (** Shall we fail hard if we encounter an issue, or should we attempt to go
     as far as possible while leaving "holes" in the generated code? *)
 let fail_hard = ref true
+
+(** if true, add the type name as a prefix
+    to the variant names.
+    Ex.:
+    In Rust:
+      {[
+        enum List = {
+          Cons(u32, Box<List>),x
+          Nil,
+        }
+      ]}
+
+    F*, if option activated:
+      {[
+        type list =
+        | ListCons : u32 -> list -> list
+        | ListNil : list
+      ]}
+
+    F*, if option not activated:
+      {[
+        type list =
+        | Cons : u32 -> list -> list
+        | Nil : list
+      ]}
+ *)
+let variant_concatenate_type_name = ref true
diff --git a/compiler/Contexts.ml b/compiler/Contexts.ml
index dac64a9a..a2ae4f16 100644
--- a/compiler/Contexts.ml
+++ b/compiler/Contexts.ml
@@ -2,7 +2,7 @@ open Types
 open Expressions
 open Values
 open LlbcAst
-module V = Values
+open LlbcAstUtils
 open ValuesUtils
 open Identifiers
 module L = Logging
@@ -112,16 +112,16 @@ let reset_global_counters () =
   fun_call_id_counter := FunCallId.generator_zero;
   dummy_var_id_counter := DummyVarId.generator_zero
 
-(** Ancestor for {!var_binder} iter visitor *)
-class ['self] iter_var_binder_base =
+(** Ancestor for {!env} iter visitor *)
+class ['self] iter_env_base =
   object (_self : 'self)
     inherit [_] iter_abs
     method visit_var_id : 'env -> var_id -> unit = fun _ _ -> ()
     method visit_dummy_var_id : 'env -> dummy_var_id -> unit = fun _ _ -> ()
   end
 
-(** Ancestor for {!var_binder} map visitor *)
-class ['self] map_var_binder_base =
+(** Ancestor for {!env} map visitor *)
+class ['self] map_env_base =
   object (_self : 'self)
     inherit [_] map_abs
     method visit_var_id : 'env -> var_id -> var_id = fun _ x -> x
@@ -135,97 +135,29 @@ type var_binder = {
   index : var_id;  (** Unique variable identifier *)
   name : string option;  (** Possible name *)
 }
-[@@deriving
-  show,
-    visitors
-      {
-        name = "iter_var_binder";
-        variety = "iter";
-        ancestors = [ "iter_var_binder_base" ];
-        nude = true (* Don't inherit {!VisitorsRuntime.iter} *);
-        concrete = true;
-      },
-    visitors
-      {
-        name = "map_var_binder";
-        variety = "map";
-        ancestors = [ "map_var_binder_base" ];
-        nude = true (* Don't inherit {!VisitorsRuntime.iter} *);
-        concrete = true;
-      }]
 
 (** A binder, for a "real" variable or a dummy variable *)
-type binder = VarBinder of var_binder | DummyBinder of dummy_var_id
-[@@deriving
-  show,
-    visitors
-      {
-        name = "iter_binder";
-        variety = "iter";
-        ancestors = [ "iter_var_binder" ];
-        nude = true (* Don't inherit {!VisitorsRuntime.iter} *);
-        concrete = true;
-      },
-    visitors
-      {
-        name = "map_binder";
-        variety = "map";
-        ancestors = [ "map_var_binder" ];
-        nude = true (* Don't inherit {!VisitorsRuntime.iter} *);
-        concrete = true;
-      }]
-
-(** Ancestor for {!env_elem} iter visitor *)
-class ['self] iter_env_elem_base =
-  object (_self : 'self)
-    inherit [_] iter_binder
-  end
-
-(** Ancestor for {!env_elem} map visitor *)
-class ['self] map_env_elem_base =
-  object (_self : 'self)
-    inherit [_] map_binder
-  end
+and binder = BVar of var_binder | BDummy of dummy_var_id
 
 (** Environment value: mapping from variable to value, abstraction (only
     used in symbolic mode) or stack frame delimiter.
-    
-    TODO: rename Var (-> Binding?)
  *)
-type env_elem =
-  | Var of binder * typed_value
+and env_elem =
+  | EBinding of binder * typed_value
       (** Variable binding - the binder is None if the variable is a dummy variable
           (we use dummy variables to store temporaries while doing bookkeeping such
            as ending borrows for instance). *)
-  | Abs of abs
-  | Frame
-[@@deriving
-  show,
-    visitors
-      {
-        name = "iter_env_elem";
-        variety = "iter";
-        ancestors = [ "iter_env_elem_base" ];
-        nude = true (* Don't inherit {!VisitorsRuntime.iter} *);
-        concrete = true;
-      },
-    visitors
-      {
-        name = "map_env_elem";
-        variety = "map";
-        ancestors = [ "map_env_elem_base" ];
-        nude = true (* Don't inherit {!VisitorsRuntime.iter} *);
-        concrete = true;
-      }]
+  | EAbs of abs
+  | EFrame
 
-type env = env_elem list
+and env = env_elem list
 [@@deriving
   show,
     visitors
       {
         name = "iter_env";
         variety = "iter";
-        ancestors = [ "iter_env_elem" ];
+        ancestors = [ "iter_env_base" ];
         nude = true (* Don't inherit {!VisitorsRuntime.iter} *);
         concrete = true;
       },
@@ -233,7 +165,7 @@ type env = env_elem list
       {
         name = "map_env";
         variety = "map";
-        ancestors = [ "map_env_elem" ];
+        ancestors = [ "map_env_base" ];
         nude = true (* Don't inherit {!VisitorsRuntime.iter} *);
         concrete = true;
       }]
@@ -258,6 +190,7 @@ type type_context = {
 type fun_context = {
   fun_decls : fun_decl FunDeclId.Map.t;
   fun_infos : FunsAnalysis.fun_info FunDeclId.Map.t;
+  regions_hierarchies : region_groups FunIdMap.t;
 }
 [@@deriving show]
 
@@ -280,48 +213,20 @@ type decls_ctx = {
 [@@deriving show]
 
 (** A reference to a trait associated type *)
-type 'r trait_type_ref = { trait_ref : 'r trait_ref; type_name : string }
-[@@deriving show, ord]
-
-type etrait_type_ref = erased_region trait_type_ref [@@deriving show, ord]
-
-type rtrait_type_ref = Types.RegionId.id Types.region trait_type_ref
-[@@deriving show, ord]
-
-type strait_type_ref = Types.RegionVarId.id Types.region trait_type_ref
+type trait_type_ref = { trait_ref : trait_ref; type_name : string }
 [@@deriving show, ord]
 
 (* TODO: correctly use the functors so as not to have a duplication below *)
-module ETraitTypeRefOrd = struct
-  type t = etrait_type_ref
+module TraitTypeRefOrd = struct
+  type t = trait_type_ref
 
-  let compare = compare_etrait_type_ref
-  let to_string = show_etrait_type_ref
-  let pp_t = pp_etrait_type_ref
-  let show_t = show_etrait_type_ref
+  let compare = compare_trait_type_ref
+  let to_string = show_trait_type_ref
+  let pp_t = pp_trait_type_ref
+  let show_t = show_trait_type_ref
 end
 
-module RTraitTypeRefOrd = struct
-  type t = rtrait_type_ref
-
-  let compare = compare_rtrait_type_ref
-  let to_string = show_rtrait_type_ref
-  let pp_t = pp_rtrait_type_ref
-  let show_t = show_rtrait_type_ref
-end
-
-module STraitTypeRefOrd = struct
-  type t = strait_type_ref
-
-  let compare = compare_strait_type_ref
-  let to_string = show_strait_type_ref
-  let pp_t = pp_strait_type_ref
-  let show_t = show_strait_type_ref
-end
-
-module ETraitTypeRefMap = Collections.MakeMap (ETraitTypeRefOrd)
-module RTraitTypeRefMap = Collections.MakeMap (RTraitTypeRefOrd)
-module STraitTypeRefMap = Collections.MakeMap (STraitTypeRefOrd)
+module TraitTypeRefMap = Collections.MakeMap (TraitTypeRefOrd)
 
 (** Evaluation context *)
 type eval_ctx = {
@@ -337,25 +242,10 @@ type eval_ctx = {
       (** The map from const generic vars to their values. Those values
           can be symbolic values or concrete values (in the latter case:
           if we run in interpreter mode) *)
-  norm_trait_etypes : ety ETraitTypeRefMap.t;
+  norm_trait_types : ty TraitTypeRefMap.t;
       (** The normalized trait types (a map from trait types to their representatives).
-          Note that this doesn't support account higher-order types. *)
-  norm_trait_rtypes : rty RTraitTypeRefMap.t;
-      (** We need this because we manipulate two kinds of types.
-          Note that we actually forbid regions from appearing both in the trait
-          references and in the constraints given to the associated types,
-          meaning that we don't have to worry about mismatches due to changes
-          in region ids.
-
-          TODO: how not to duplicate?
-       *)
-  norm_trait_stypes : sty STraitTypeRefMap.t;
-      (** We sometimes need to normalize types in non-instantiated signatures.
-
-          Note that we either need to use the etypes/rtypes maps, or the stypes map.
-          This means that we either compute the maps for etypes and rtypes, or compute
-          the one for stypes (we don't always compute and carry all the maps).
-       *)
+          Note that this doesn't take into account higher-order type constraints
+          (of the shape `for<'a> ...`). *)
   env : env;
   ended_regions : RegionId.Set.t;
 }
@@ -363,18 +253,14 @@ type eval_ctx = {
 
 let lookup_type_var_opt (ctx : eval_ctx) (vid : TypeVarId.id) : type_var option
     =
-  if TypeVarId.to_int vid < List.length ctx.type_vars then
-    Some (TypeVarId.nth ctx.type_vars vid)
-  else None
+  TypeVarId.nth_opt ctx.type_vars vid
 
 let lookup_type_var (ctx : eval_ctx) (vid : TypeVarId.id) : type_var =
   TypeVarId.nth ctx.type_vars vid
 
 let lookup_const_generic_var_opt (ctx : eval_ctx) (vid : ConstGenericVarId.id) :
     const_generic_var option =
-  if ConstGenericVarId.to_int vid < List.length ctx.const_generic_vars then
-    Some (ConstGenericVarId.nth ctx.const_generic_vars vid)
-  else None
+  ConstGenericVarId.nth_opt ctx.const_generic_vars vid
 
 let lookup_const_generic_var (ctx : eval_ctx) (vid : ConstGenericVarId.id) :
     const_generic_var =
@@ -389,10 +275,10 @@ let env_lookup_var (env : env) (vid : VarId.id) : var_binder * typed_value =
     match env with
     | [] ->
         raise (Invalid_argument ("Variable not found: " ^ VarId.to_string vid))
-    | Var (VarBinder var, v) :: env' ->
+    | EBinding (BVar var, v) :: env' ->
         if var.index = vid then (var, v) else lookup env'
-    | (Var (DummyBinder _, _) | Abs _) :: env' -> lookup env'
-    | Frame :: _ -> raise (Failure "End of frame")
+    | (EBinding (BDummy _, _) | EAbs _) :: env' -> lookup env'
+    | EFrame :: _ -> raise (Failure "End of frame")
   in
   lookup env
 
@@ -440,11 +326,11 @@ let env_update_var_value (env : env) (vid : VarId.id) (nv : typed_value) : env =
   let rec update env =
     match env with
     | [] -> raise (Failure "Unexpected")
-    | Var ((VarBinder b as var), v) :: env' ->
-        if b.index = vid then Var (var, nv) :: env'
-        else Var (var, v) :: update env'
-    | ((Var (DummyBinder _, _) | Abs _) as ee) :: env' -> ee :: update env'
-    | Frame :: _ -> raise (Failure "End of frame")
+    | EBinding ((BVar b as var), v) :: env' ->
+        if b.index = vid then EBinding (var, nv) :: env'
+        else EBinding (var, v) :: update env'
+    | ((EBinding (BDummy _, _) | EAbs _) as ee) :: env' -> ee :: update env'
+    | EFrame :: _ -> raise (Failure "End of frame")
   in
   update env
 
@@ -466,9 +352,9 @@ let ctx_update_var_value (ctx : eval_ctx) (vid : VarId.id) (nv : typed_value) :
     is important).
 *)
 let ctx_push_var (ctx : eval_ctx) (var : var) (v : typed_value) : eval_ctx =
-  assert (var.var_ty = v.ty);
+  assert (TypesUtils.ty_is_ety var.var_ty && var.var_ty = v.ty);
   let bv = var_to_binder var in
-  { ctx with env = Var (VarBinder bv, v) :: ctx.env }
+  { ctx with env = EBinding (BVar bv, v) :: ctx.env }
 
 (** Push a list of variables.
 
@@ -484,15 +370,16 @@ let ctx_push_vars (ctx : eval_ctx) (vars : (var * typed_value) list) : eval_ctx
           (List.map
              (fun (var, value) ->
                (* We can unfortunately not use Print because it depends on Contexts... *)
-               show_var var ^ " -> " ^ V.show_typed_value value)
+               show_var var ^ " -> " ^ show_typed_value value)
              vars)));
   assert (
     List.for_all
-      (fun (var, (value : typed_value)) -> var.var_ty = value.ty)
+      (fun (var, (value : typed_value)) ->
+        TypesUtils.ty_is_ety var.var_ty && var.var_ty = value.ty)
       vars);
   let vars =
     List.map
-      (fun (var, value) -> Var (VarBinder (var_to_binder var), value))
+      (fun (var, value) -> EBinding (BVar (var_to_binder var), value))
       vars
   in
   let vars = List.rev vars in
@@ -501,7 +388,7 @@ let ctx_push_vars (ctx : eval_ctx) (vars : (var * typed_value) list) : eval_ctx
 (** Push a dummy variable in the context's environment. *)
 let ctx_push_dummy_var (ctx : eval_ctx) (vid : DummyVarId.id) (v : typed_value)
     : eval_ctx =
-  { ctx with env = Var (DummyBinder vid, v) :: ctx.env }
+  { ctx with env = EBinding (BDummy vid, v) :: ctx.env }
 
 (** Remove a dummy variable from a context's environment. *)
 let ctx_remove_dummy_var (ctx : eval_ctx) (vid : DummyVarId.id) :
@@ -509,7 +396,7 @@ let ctx_remove_dummy_var (ctx : eval_ctx) (vid : DummyVarId.id) :
   let rec remove_var (env : env) : env * typed_value =
     match env with
     | [] -> raise (Failure "Could not lookup a dummy variable")
-    | Var (DummyBinder vid', v) :: env when vid' = vid -> (env, v)
+    | EBinding (BDummy vid', v) :: env when vid' = vid -> (env, v)
     | ee :: env ->
         let env, v = remove_var env in
         (ee :: env, v)
@@ -522,53 +409,61 @@ let ctx_lookup_dummy_var (ctx : eval_ctx) (vid : DummyVarId.id) : typed_value =
   let rec lookup_var (env : env) : typed_value =
     match env with
     | [] -> raise (Failure "Could not lookup a dummy variable")
-    | Var (DummyBinder vid', v) :: _env when vid' = vid -> v
+    | EBinding (BDummy vid', v) :: _env when vid' = vid -> v
     | _ :: env -> lookup_var env
   in
   lookup_var ctx.env
 
+let erase_regions (ty : ty) : ty =
+  let v =
+    object
+      inherit [_] map_ty
+      method! visit_region _ _ = RErased
+    end
+  in
+  v#visit_ty () ty
+
 (** Push an uninitialized variable (which thus maps to {!constructor:Values.value.Bottom}) *)
 let ctx_push_uninitialized_var (ctx : eval_ctx) (var : var) : eval_ctx =
-  ctx_push_var ctx var (mk_bottom var.var_ty)
+  ctx_push_var ctx var (mk_bottom (erase_regions var.var_ty))
 
 (** Push a list of uninitialized variables (which thus map to {!constructor:Values.value.Bottom}) *)
 let ctx_push_uninitialized_vars (ctx : eval_ctx) (vars : var list) : eval_ctx =
-  let vars = List.map (fun v -> (v, mk_bottom v.var_ty)) vars in
+  let vars = List.map (fun v -> (v, mk_bottom (erase_regions v.var_ty))) vars in
   ctx_push_vars ctx vars
 
-let env_find_abs (env : env) (pred : V.abs -> bool) : V.abs option =
+let env_find_abs (env : env) (pred : abs -> bool) : abs option =
   let rec lookup env =
     match env with
     | [] -> None
-    | Var (_, _) :: env' -> lookup env'
-    | Abs abs :: env' -> if pred abs then Some abs else lookup env'
-    | Frame :: env' -> lookup env'
+    | EBinding (_, _) :: env' -> lookup env'
+    | EAbs abs :: env' -> if pred abs then Some abs else lookup env'
+    | EFrame :: env' -> lookup env'
   in
   lookup env
 
-let env_lookup_abs (env : env) (abs_id : V.AbstractionId.id) : V.abs =
+let env_lookup_abs (env : env) (abs_id : AbstractionId.id) : abs =
   Option.get (env_find_abs env (fun abs -> abs.abs_id = abs_id))
 
 (** Remove an abstraction from the context, as well as all the references to
     this abstraction (for instance, remove the abs id from all the parent sets
     of all the other abstractions).
  *)
-let env_remove_abs (env : env) (abs_id : V.AbstractionId.id) :
-    env * V.abs option =
-  let rec remove (env : env) : env * V.abs option =
+let env_remove_abs (env : env) (abs_id : AbstractionId.id) : env * abs option =
+  let rec remove (env : env) : env * abs option =
     match env with
     | [] -> raise (Failure "Unreachable")
-    | Frame :: _ -> (env, None)
-    | Var (bv, v) :: env ->
+    | EFrame :: _ -> (env, None)
+    | EBinding (bv, v) :: env ->
         let env, abs_opt = remove env in
-        (Var (bv, v) :: env, abs_opt)
-    | Abs abs :: env ->
+        (EBinding (bv, v) :: env, abs_opt)
+    | EAbs abs :: env ->
         if abs.abs_id = abs_id then (env, Some abs)
         else
           let env, abs_opt = remove env in
           (* Update the parents set *)
-          let parents = V.AbstractionId.Set.remove abs_id abs.parents in
-          (Abs { abs with V.parents } :: env, abs_opt)
+          let parents = AbstractionId.Set.remove abs_id abs.parents in
+          (EAbs { abs with parents } :: env, abs_opt)
   in
   remove env
 
@@ -579,50 +474,50 @@ let env_remove_abs (env : env) (abs_id : V.AbstractionId.id) :
     we also substitute the abstraction id wherever it is used (i.e., in the
     parent sets of the other abstractions).
  *)
-let env_subst_abs (env : env) (abs_id : V.AbstractionId.id) (nabs : V.abs) :
-    env * V.abs option =
-  let rec update (env : env) : env * V.abs option =
+let env_subst_abs (env : env) (abs_id : AbstractionId.id) (nabs : abs) :
+    env * abs option =
+  let rec update (env : env) : env * abs option =
     match env with
     | [] -> raise (Failure "Unreachable")
-    | Frame :: _ -> (* We're done *) (env, None)
-    | Var (bv, v) :: env ->
+    | EFrame :: _ -> (* We're done *) (env, None)
+    | EBinding (bv, v) :: env ->
         let env, opt_abs = update env in
-        (Var (bv, v) :: env, opt_abs)
-    | Abs abs :: env ->
-        if abs.abs_id = abs_id then (Abs nabs :: env, Some abs)
+        (EBinding (bv, v) :: env, opt_abs)
+    | EAbs abs :: env ->
+        if abs.abs_id = abs_id then (EAbs nabs :: env, Some abs)
         else
           let env, opt_abs = update env in
           (* Update the parents set *)
           let parents = abs.parents in
           let parents =
-            if V.AbstractionId.Set.mem abs_id parents then
-              let parents = V.AbstractionId.Set.remove abs_id parents in
-              V.AbstractionId.Set.add nabs.abs_id parents
+            if AbstractionId.Set.mem abs_id parents then
+              let parents = AbstractionId.Set.remove abs_id parents in
+              AbstractionId.Set.add nabs.abs_id parents
             else parents
           in
-          (Abs { abs with V.parents } :: env, opt_abs)
+          (EAbs { abs with parents } :: env, opt_abs)
   in
   update env
 
-let ctx_lookup_abs (ctx : eval_ctx) (abs_id : V.AbstractionId.id) : V.abs =
+let ctx_lookup_abs (ctx : eval_ctx) (abs_id : AbstractionId.id) : abs =
   env_lookup_abs ctx.env abs_id
 
-let ctx_find_abs (ctx : eval_ctx) (p : V.abs -> bool) : V.abs option =
+let ctx_find_abs (ctx : eval_ctx) (p : abs -> bool) : abs option =
   env_find_abs ctx.env p
 
 (** See the comments for {!env_remove_abs} *)
-let ctx_remove_abs (ctx : eval_ctx) (abs_id : V.AbstractionId.id) :
-    eval_ctx * V.abs option =
+let ctx_remove_abs (ctx : eval_ctx) (abs_id : AbstractionId.id) :
+    eval_ctx * abs option =
   let env, abs = env_remove_abs ctx.env abs_id in
   ({ ctx with env }, abs)
 
 (** See the comments for {!env_subst_abs} *)
-let ctx_subst_abs (ctx : eval_ctx) (abs_id : V.AbstractionId.id) (nabs : V.abs)
-    : eval_ctx * V.abs option =
+let ctx_subst_abs (ctx : eval_ctx) (abs_id : AbstractionId.id) (nabs : abs) :
+    eval_ctx * abs option =
   let env, abs_opt = env_subst_abs ctx.env abs_id nabs in
   ({ ctx with env }, abs_opt)
 
-let ctx_set_abs_can_end (ctx : eval_ctx) (abs_id : V.AbstractionId.id)
+let ctx_set_abs_can_end (ctx : eval_ctx) (abs_id : AbstractionId.id)
     (can_end : bool) : eval_ctx =
   let abs = ctx_lookup_abs ctx abs_id in
   let abs = { abs with can_end } in
@@ -630,7 +525,7 @@ let ctx_set_abs_can_end (ctx : eval_ctx) (abs_id : V.AbstractionId.id)
 
 let ctx_type_decl_is_rec (ctx : eval_ctx) (id : TypeDeclId.id) : bool =
   let decl_group = TypeDeclId.Map.find id ctx.type_context.type_decls_groups in
-  match decl_group with Rec _ -> true | NonRec _ -> false
+  match decl_group with RecGroup _ -> true | NonRecGroup _ -> false
 
 (** Visitor to iterate over the values in the *current* frame *)
 class ['self] iter_frame =
@@ -641,7 +536,7 @@ class ['self] iter_frame =
       fun acc env ->
         match env with
         | [] -> ()
-        | Frame :: _ -> (* We stop here *) ()
+        | EFrame :: _ -> (* We stop here *) ()
         | em :: env ->
             self#visit_env_elem acc em;
             self#visit_env acc env
@@ -656,7 +551,7 @@ class ['self] map_frame_concrete =
       fun acc env ->
         match env with
         | [] -> []
-        | Frame :: env -> (* We stop here *) Frame :: env
+        | EFrame :: env -> (* We stop here *) EFrame :: env
         | em :: env ->
             let em = self#visit_env_elem acc em in
             let env = self#visit_env acc env in
@@ -683,20 +578,20 @@ class ['self] map_eval_ctx =
         { ctx with env }
   end
 
-let env_iter_abs (f : V.abs -> unit) (env : env) : unit =
+let env_iter_abs (f : abs -> unit) (env : env) : unit =
   List.iter
     (fun (ee : env_elem) ->
-      match ee with Var _ | Frame -> () | Abs abs -> f abs)
+      match ee with EBinding _ | EFrame -> () | EAbs abs -> f abs)
     env
 
-let env_map_abs (f : V.abs -> V.abs) (env : env) : env =
+let env_map_abs (f : abs -> abs) (env : env) : env =
   List.map
     (fun (ee : env_elem) ->
-      match ee with Var _ | Frame -> ee | Abs abs -> Abs (f abs))
+      match ee with EBinding _ | EFrame -> ee | EAbs abs -> EAbs (f abs))
     env
 
-let env_filter_abs (f : V.abs -> bool) (env : env) : env =
+let env_filter_abs (f : abs -> bool) (env : env) : env =
   List.filter
     (fun (ee : env_elem) ->
-      match ee with Var _ | Frame -> true | Abs abs -> f abs)
+      match ee with EBinding _ | EFrame -> true | EAbs abs -> f abs)
     env
diff --git a/compiler/Cps.ml b/compiler/Cps.ml
index c0dd0ae2..a3c8f1e1 100644
--- a/compiler/Cps.ml
+++ b/compiler/Cps.ml
@@ -1,10 +1,8 @@
 (** This module defines various utilities to write the interpretation functions
     in continuation passing style. *)
 
-module T = Types
-module V = Values
-module C = Contexts
-module SA = SymbolicAst
+open Values
+open Contexts
 
 (** TODO: change the name *)
 type eval_error = EPanic
@@ -16,9 +14,9 @@ type statement_eval_res =
   | Continue of int
   | Return
   | Panic
-  | LoopReturn of V.loop_id
+  | LoopReturn of loop_id
       (** We reached a return statement *while inside a loop* *)
-  | EndEnterLoop of V.loop_id * V.typed_value V.SymbolicValueId.Map.t
+  | EndEnterLoop of loop_id * typed_value SymbolicValueId.Map.t
       (** When we enter a loop, we delegate the end of the function is
           synthesized with a call to the loop translation. We use this
           evaluation result to transmit the fact that we end evaluation
@@ -27,7 +25,7 @@ type statement_eval_res =
           We provide the list of values for the translated loop function call
           (or to be more precise the input values instantiation).
        *)
-  | EndContinue of V.loop_id * V.typed_value V.SymbolicValueId.Map.t
+  | EndContinue of loop_id * typed_value SymbolicValueId.Map.t
       (** For loop translations: we end with a continue (i.e., a recursive call
           to the translation for the loop body).
 
@@ -36,21 +34,21 @@ type statement_eval_res =
        *)
 [@@deriving show]
 
-type eval_result = SA.expression option
+type eval_result = SymbolicAst.expression option
 
 (** Continuation function *)
-type m_fun = C.eval_ctx -> eval_result
+type m_fun = eval_ctx -> eval_result
 
 (** Continuation taking another continuation as parameter *)
 type cm_fun = m_fun -> m_fun
 
 (** Continuation taking a typed value as parameter - TODO: use more *)
-type typed_value_m_fun = V.typed_value -> m_fun
+type typed_value_m_fun = typed_value -> m_fun
 
 (** Continuation taking another continuation as parameter and a typed
     value as parameter.
  *)
-type typed_value_cm_fun = V.typed_value -> cm_fun
+type typed_value_cm_fun = typed_value -> cm_fun
 
 (** Type of a continuation used when evaluating a statement *)
 type st_m_fun = statement_eval_res -> m_fun
@@ -59,13 +57,13 @@ type st_m_fun = statement_eval_res -> m_fun
 type st_cm_fun = st_m_fun -> m_fun
 
 (** Convert a unit function to a cm function *)
-let unit_to_cm_fun (f : C.eval_ctx -> unit) : cm_fun =
+let unit_to_cm_fun (f : eval_ctx -> unit) : cm_fun =
  fun cf ctx ->
   f ctx;
   cf ctx
 
 (** *)
-let update_to_cm_fun (f : C.eval_ctx -> C.eval_ctx) : cm_fun =
+let update_to_cm_fun (f : eval_ctx -> eval_ctx) : cm_fun =
  fun cf ctx ->
   let ctx = f ctx in
   cf ctx
@@ -75,10 +73,10 @@ let update_to_cm_fun (f : C.eval_ctx -> C.eval_ctx) : cm_fun =
 let comp (f : 'c -> 'd -> 'e) (g : ('a -> 'b) -> 'c) : ('a -> 'b) -> 'd -> 'e =
  fun cf ctx -> f (g cf) ctx
 
-let comp_unit (f : cm_fun) (g : C.eval_ctx -> unit) : cm_fun =
+let comp_unit (f : cm_fun) (g : eval_ctx -> unit) : cm_fun =
   comp f (unit_to_cm_fun g)
 
-let comp_update (f : cm_fun) (g : C.eval_ctx -> C.eval_ctx) : cm_fun =
+let comp_update (f : cm_fun) (g : eval_ctx -> eval_ctx) : cm_fun =
   comp f (update_to_cm_fun g)
 
 (** This is just a test, to check that {!comp} is general enough to handle a case
@@ -88,8 +86,8 @@ let comp_update (f : cm_fun) (g : C.eval_ctx -> C.eval_ctx) : cm_fun =
     Keeping this here also makes it a good reference, when one wants to figure
     out the signatures he should use for such a composition.
  *)
-let comp_ret_val (f : (V.typed_value -> m_fun) -> m_fun)
-    (g : m_fun -> V.typed_value -> m_fun) : cm_fun =
+let comp_ret_val (f : (typed_value -> m_fun) -> m_fun)
+    (g : m_fun -> typed_value -> m_fun) : cm_fun =
   comp f g
 
 let apply (f : cm_fun) (g : m_fun) : m_fun = fun ctx -> f g ctx
diff --git a/compiler/Extract.ml b/compiler/Extract.ml
index d04f5c1d..c8c16c08 100644
--- a/compiler/Extract.ml
+++ b/compiler/Extract.ml
@@ -6,7 +6,6 @@
 open Pure
 open PureUtils
 open TranslateCore
-open ExtractBase
 open Config
 include ExtractTypes
 
@@ -27,8 +26,7 @@ let extract_fun_decl_register_names (ctx : extraction_ctx)
       let builtin =
         let open ExtractBuiltin in
         let funs_map = builtin_funs_map () in
-        let sname = name_to_simple_name def.fwd.f.basename in
-        SimpleNameMap.find_opt sname funs_map
+        match_name_find_opt ctx.trans_ctx def.fwd.f.llbc_name funs_map
       in
       (* Use the builtin names if necessary *)
       match builtin with
@@ -51,7 +49,7 @@ let extract_fun_decl_register_names (ctx : extraction_ctx)
             (fun ctx (f : fun_decl) ->
               let open ExtractBuiltin in
               let fun_id =
-                (Pure.FunId (Regular f.def_id), f.loop_id, f.back_id)
+                (Pure.FunId (FRegular f.def_id), f.loop_id, f.back_id)
               in
               let fun_info =
                 List.find_opt
@@ -65,7 +63,7 @@ let extract_fun_decl_register_names (ctx : extraction_ctx)
                   raise
                     (Failure
                        ("Not found: "
-                       ^ Names.name_to_string f.basename
+                       ^ name_to_string ctx f.llbc_name
                        ^ ", "
                        ^ Print.option_to_string Pure.show_loop_id f.loop_id
                        ^ Print.option_to_string Pure.show_region_group_id
@@ -124,7 +122,7 @@ let extract_adt_g_value
     (inside : bool) (variant_id : VariantId.id option) (field_values : 'v list)
     (ty : ty) : extraction_ctx =
   match ty with
-  | Adt (Tuple, generics) ->
+  | TAdt (TTuple, generics) ->
       (* Tuple *)
       (* For now, we only support fully applied tuple constructors *)
       assert (List.length generics.types = List.length field_values);
@@ -146,7 +144,7 @@ let extract_adt_g_value
         in
         F.pp_print_string fmt ")";
         ctx)
-  | Adt (adt_id, _) ->
+  | TAdt (adt_id, _) ->
       (* "Regular" ADT *)
 
       (* If we are generating a pattern for a let-binding and we target Lean,
@@ -178,7 +176,7 @@ let extract_adt_g_value
           | Some vid -> (
               (* In the case of Lean, we might have to add the type name as a prefix *)
               match (!backend, adt_id) with
-              | Lean, Assumed _ ->
+              | Lean, TAssumed _ ->
                   ctx_get_type adt_id ctx ^ "." ^ ctx_get_variant adt_id vid ctx
               | _ -> ctx_get_variant adt_id vid ctx)
           | None -> ctx_get_struct adt_id ctx
@@ -212,7 +210,7 @@ let fun_builtin_filter_types (id : FunDeclId.id) (types : 'a list)
         let decl = FunDeclId.Map.find id ctx.trans_funs in
         let err =
           "Ill-formed builtin information for function "
-          ^ Names.name_to_string decl.fwd.f.basename
+          ^ name_to_string ctx decl.fwd.f.llbc_name
           ^ ": "
           ^ string_of_int (List.length filter)
           ^ " filtering arguments provided for "
@@ -237,12 +235,10 @@ let rec extract_typed_pattern (ctx : extraction_ctx) (fmt : F.formatter)
     (is_let : bool) (inside : bool) (v : typed_pattern) : extraction_ctx =
   match v.value with
   | PatConstant cv ->
-      ctx.fmt.extract_literal fmt inside cv;
+      extract_literal fmt inside cv;
       ctx
   | PatVar (v, _) ->
-      let vname =
-        ctx.fmt.var_basename ctx.names_maps.names_map.names_set v.basename v.ty
-      in
+      let vname = ctx_compute_var_basename ctx v.basename v.ty in
       let ctx, vname = ctx_add_var vname v.id ctx in
       F.pp_print_string fmt vname;
       ctx
@@ -275,7 +271,7 @@ let rec extract_texpression (ctx : extraction_ctx) (fmt : F.formatter)
   | CVar var_id ->
       let var_name = ctx_get_const_generic_var var_id ctx in
       F.pp_print_string fmt var_name
-  | Const cv -> ctx.fmt.extract_literal fmt inside cv
+  | Const cv -> extract_literal fmt inside cv
   | App _ ->
       let app, args = destruct_apps e in
       extract_App ctx fmt inside app args
@@ -355,10 +351,10 @@ and extract_function_call (ctx : extraction_ctx) (fmt : F.formatter)
        * Note that the way we generate the translation, we shouldn't get the
        * case where we have no argument (all functions are fully instantiated,
        * and no AST transformation introduces partial calls). *)
-      ctx.fmt.extract_unop (extract_texpression ctx fmt) fmt inside unop arg
+      extract_unop (extract_texpression ctx fmt) fmt inside unop arg
   | Binop (binop, int_ty), [ arg0; arg1 ] ->
       (* Number of arguments: similar to unop *)
-      ctx.fmt.extract_binop
+      extract_binop
         (extract_texpression ctx fmt)
         fmt inside binop int_ty arg0 arg1
   | Fun fun_id, _ ->
@@ -441,7 +437,7 @@ and extract_function_call (ctx : extraction_ctx) (fmt : F.formatter)
             (* Provided method: we see it as a regular function call, and use
                the function name *)
             let fun_id =
-              FromLlbc (FunId (Regular method_id.id), lp_id, rg_id)
+              FromLlbc (FunId (FRegular method_id.id), lp_id, rg_id)
             in
             let fun_name = ctx_get_function fun_id ctx in
             F.pp_print_string fmt fun_name;
@@ -467,7 +463,7 @@ and extract_function_call (ctx : extraction_ctx) (fmt : F.formatter)
       *)
       let types =
         match fun_id with
-        | FromLlbc (FunId (Regular id), _, _) ->
+        | FromLlbc (FunId (FRegular id), _, _) ->
             fun_builtin_filter_types id generics.types ctx
         | _ -> Result.Ok generics.types
       in
@@ -506,7 +502,7 @@ and extract_function_call (ctx : extraction_ctx) (fmt : F.formatter)
 and extract_adt_cons (ctx : extraction_ctx) (fmt : F.formatter) (inside : bool)
     (adt_cons : adt_cons_id) (generics : generic_args) (args : texpression list)
     : unit =
-  let e_ty = Adt (adt_cons.adt_id, generics) in
+  let e_ty = TAdt (adt_cons.adt_id, generics) in
   let is_single_pat = false in
   let _ =
     extract_adt_g_value
@@ -871,7 +867,7 @@ and extract_StructUpdate (ctx : extraction_ctx) (fmt : F.formatter)
      thus extracted to unit. We need to check that by looking up the definition *)
   let extract_as_unit =
     match (!backend, supd.struct_id) with
-    | HOL4, AdtId adt_id ->
+    | HOL4, TAdtId adt_id ->
         let d = TypeDeclId.Map.find adt_id ctx.trans_ctx.type_ctx.type_decls in
         d.kind = Struct []
     | _ -> false
@@ -885,7 +881,7 @@ and extract_StructUpdate (ctx : extraction_ctx) (fmt : F.formatter)
        - this is an array
     *)
     match supd.struct_id with
-    | AdtId _ ->
+    | TAdtId _ ->
         F.pp_open_hvbox fmt 0;
         F.pp_open_hvbox fmt ctx.indent_incr;
         (* Inner/outer brackets: there are several syntaxes for the field updates.
@@ -966,7 +962,7 @@ and extract_StructUpdate (ctx : extraction_ctx) (fmt : F.formatter)
         if need_paren then F.pp_print_string fmt ")";
         print_bracket false orb;
         F.pp_close_box fmt ()
-    | Assumed Array ->
+    | TAssumed TArray ->
         (* Open the boxes *)
         F.pp_open_hvbox fmt ctx.indent_incr;
         let need_paren = inside in
@@ -974,7 +970,7 @@ and extract_StructUpdate (ctx : extraction_ctx) (fmt : F.formatter)
         (* Open the box for `Array.replicate T N [` *)
         F.pp_open_hovbox fmt ctx.indent_incr;
         (* Print the array constructor *)
-        let cs = ctx_get_struct (Assumed Array) ctx in
+        let cs = ctx_get_struct (TAssumed TArray) ctx in
         F.pp_print_string fmt cs;
         (* Print the parameters *)
         let _, generics = ty_as_adt e_ty in
@@ -1048,7 +1044,8 @@ let extract_fun_parameters (space : bool ref) (ctx : extraction_ctx)
   (* Add the type parameters - note that we need those bindings only for the
    * body translation (they are not top-level) *)
   let ctx, type_params, cg_params, trait_clauses =
-    ctx_add_generic_params def.signature.generics ctx
+    ctx_add_generic_params def.llbc_name def.signature.llbc_generics
+      def.signature.generics ctx
   in
   (* Print the generics *)
   (* Open a box for the generics *)
@@ -1136,8 +1133,9 @@ let extract_template_fstar_decreases_clause (ctx : extraction_ctx)
   (* Add a break before *)
   F.pp_print_break fmt 0 0;
   (* Print a comment to link the extracted type to its original rust definition *)
-  extract_comment fmt
-    [ "[" ^ Print.fun_name_to_string def.basename ^ "]: decreases clause" ];
+  extract_comment_with_span fmt
+    [ "[" ^ name_to_string ctx def.llbc_name ^ "]: decreases clause" ]
+    def.meta.span;
   F.pp_print_space fmt ();
   (* Open a box for the definition, so that whenever possible it gets printed on
    * one line *)
@@ -1198,8 +1196,9 @@ let extract_template_lean_termination_and_decreasing (ctx : extraction_ctx)
   (* Add a break before *)
   F.pp_print_break fmt 0 0;
   (* Print a comment to link the extracted type to its original rust definition *)
-  extract_comment fmt
-    [ "[" ^ Print.fun_name_to_string def.basename ^ "]: termination measure" ];
+  extract_comment_with_span fmt
+    [ "[" ^ name_to_string ctx def.llbc_name ^ "]: termination measure" ]
+    def.meta.span;
   F.pp_print_space fmt ();
   (* Open a box for the definition, so that whenever possible it gets printed on
    * one line *)
@@ -1252,8 +1251,9 @@ let extract_template_lean_termination_and_decreasing (ctx : extraction_ctx)
   let def_name = ctx_get_decreases_proof def.def_id def.loop_id ctx in
   (* syntax <def_name> term ... term : tactic *)
   F.pp_print_break fmt 0 0;
-  extract_comment fmt
-    [ "[" ^ Print.fun_name_to_string def.basename ^ "]: decreases_by tactic" ];
+  extract_comment_with_span fmt
+    [ "[" ^ name_to_string ctx def.llbc_name ^ "]: decreases_by tactic" ]
+    def.meta.span;
   F.pp_print_space fmt ();
   F.pp_open_hvbox fmt 0;
   F.pp_print_string fmt "syntax \"";
@@ -1286,10 +1286,10 @@ let extract_fun_comment (ctx : extraction_ctx) (fmt : F.formatter)
     (def : fun_decl) : unit =
   let { keep_fwd; num_backs } =
     PureUtils.RegularFunIdMap.find
-      (Pure.FunId (Regular def.def_id), def.loop_id, def.back_id)
+      (Pure.FunId (FRegular def.def_id), def.loop_id, def.back_id)
       ctx.fun_name_info
   in
-  let comment_pre = "[" ^ Print.fun_name_to_string def.basename ^ "]: " in
+  let comment_pre = "[" ^ name_to_string ctx def.llbc_name ^ "]: " in
   let comment =
     let loop_comment =
       match def.loop_id with
@@ -1314,7 +1314,7 @@ let extract_fun_comment (ctx : extraction_ctx) (fmt : F.formatter)
     | [ s ] -> [ comment_pre ^ loop_comment ^ s ]
     | s :: sl -> (comment_pre ^ loop_comment ^ s) :: sl
   in
-  extract_comment fmt comment
+  extract_comment_with_span fmt comment def.meta.span
 
 (** Extract a function declaration.
 
@@ -1357,7 +1357,7 @@ let extract_fun_decl_gen (ctx : extraction_ctx) (fmt : F.formatter)
     is_opaque_coq && def.signature.generics <> empty_generic_params
   in
   (* Print the qualifier ("assume", etc.). *)
-  let qualif = ctx.fmt.fun_decl_kind_to_qualif kind in
+  let qualif = fun_decl_kind_to_qualif kind in
   (match qualif with
   | Some qualif ->
       F.pp_print_string fmt qualif;
@@ -1579,7 +1579,10 @@ let extract_fun_decl_hol4_opaque (ctx : extraction_ctx) (fmt : F.formatter)
   assert (def.signature.generics.const_generics = []);
   (* Add the type/const gen parameters - note that we need those bindings
      only for the generation of the type (they are not top-level) *)
-  let ctx, _, _, _ = ctx_add_generic_params def.signature.generics ctx in
+  let ctx, _, _, _ =
+    ctx_add_generic_params def.llbc_name def.signature.llbc_generics
+      def.signature.generics ctx
+  in
   (* Add breaks to insert new lines between definitions *)
   F.pp_print_break fmt 0 0;
   (* Open a box for the whole definition *)
@@ -1653,7 +1656,7 @@ let extract_global_decl_body_gen (ctx : extraction_ctx) (fmt : F.formatter)
   (* Open "QUALIF NAME : TYPE =" box (depth=1) *)
   F.pp_open_hovbox fmt ctx.indent_incr;
   (* Print "QUALIF NAME " *)
-  (match ctx.fmt.fun_decl_kind_to_qualif kind with
+  (match fun_decl_kind_to_qualif kind with
   | Some qualif ->
       F.pp_print_string fmt qualif;
       F.pp_print_space fmt ()
@@ -1766,13 +1769,15 @@ let extract_global_decl (ctx : extraction_ctx) (fmt : F.formatter)
 
   (* Add a break then the name of the corresponding LLBC declaration *)
   F.pp_print_break fmt 0 0;
-  extract_comment fmt [ "[" ^ Print.global_name_to_string global.name ^ "]" ];
+  extract_comment_with_span fmt
+    [ "[" ^ name_to_string ctx global.name ^ "]" ]
+    global.meta.span;
   F.pp_print_space fmt ();
 
   let decl_name = ctx_get_global global.def_id ctx in
   let body_name =
     ctx_get_function
-      (FromLlbc (Pure.FunId (Regular global.body_id), None, None))
+      (FromLlbc (Pure.FunId (FRegular global.body), None, None))
       ctx
   in
 
@@ -1820,11 +1825,11 @@ let extract_trait_decl_register_parent_clause_names (ctx : extraction_ctx)
     | None ->
         List.map
           (fun (c : trait_clause) ->
-            let name = ctx.fmt.trait_parent_clause_name trait_decl c in
+            let name = ctx_compute_trait_parent_clause_name ctx trait_decl c in
             (* Add a prefix if necessary *)
             let name =
               if !Config.record_fields_short_names then name
-              else ctx.fmt.trait_decl_name trait_decl ^ name
+              else ctx_compute_trait_decl_name ctx trait_decl ^ name
             in
             (c.clause_id, name))
           trait_decl.parent_clauses
@@ -1851,11 +1856,11 @@ let extract_trait_decl_register_constant_names (ctx : extraction_ctx)
     | None ->
         List.map
           (fun (item_name, _) ->
-            let name = ctx.fmt.trait_const_name trait_decl item_name in
+            let name = ctx_compute_trait_const_name ctx trait_decl item_name in
             (* Add a prefix if necessary *)
             let name =
               if !Config.record_fields_short_names then name
-              else ctx.fmt.trait_decl_name trait_decl ^ name
+              else ctx_compute_trait_decl_name ctx trait_decl ^ name
             in
             (item_name, name))
           consts
@@ -1883,19 +1888,21 @@ let extract_trait_decl_type_names (ctx : extraction_ctx)
     match builtin_info with
     | None ->
         let compute_type_name (item_name : string) : string =
-          let type_name = ctx.fmt.trait_type_name trait_decl item_name in
+          let type_name =
+            ctx_compute_trait_type_name ctx trait_decl item_name
+          in
           if !Config.record_fields_short_names then type_name
-          else ctx.fmt.trait_decl_name trait_decl ^ type_name
+          else ctx_compute_trait_decl_name ctx trait_decl ^ type_name
         in
         let compute_clause_name (item_name : string) (clause : trait_clause) :
             TraitClauseId.id * string =
           let name =
-            ctx.fmt.trait_type_clause_name trait_decl item_name clause
+            ctx_compute_trait_type_clause_name ctx trait_decl item_name clause
           in
           (* Add a prefix if necessary *)
           let name =
             if !Config.record_fields_short_names then name
-            else ctx.fmt.trait_decl_name trait_decl ^ name
+            else ctx_compute_trait_decl_name ctx trait_decl ^ name
           in
           (clause.clause_id, name)
         in
@@ -1958,14 +1965,16 @@ let extract_trait_decl_method_names (ctx : extraction_ctx)
               =
             (* We do something special to reuse the [ctx_compute_fun_decl]
                function. TODO: make it cleaner. *)
-            let basename : name = [ Ident item_name ] in
-            let f = { f with basename } in
+            let llbc_name : Types.name =
+              [ Types.PeIdent (item_name, Disambiguator.zero) ]
+            in
+            let f = { f with llbc_name } in
             let trans = A.FunDeclId.Map.find f.def_id ctx.trans_funs in
             let name = ctx_compute_fun_name trans f ctx in
             (* Add a prefix if necessary *)
             let name =
               if !Config.record_fields_short_names then name
-              else ctx.fmt.trait_decl_name trait_decl ^ "_" ^ name
+              else ctx_compute_trait_decl_name ctx trait_decl ^ "_" ^ name
             in
             (f.back_id, name)
           in
@@ -1991,7 +2000,7 @@ let extract_trait_decl_method_names (ctx : extraction_ctx)
               | None ->
                   let err =
                     "Ill-formed builtin information for trait decl \""
-                    ^ Names.name_to_string trait_decl.name
+                    ^ name_to_string ctx trait_decl.llbc_name
                     ^ "\", method \"" ^ item_name
                     ^ "\": could not find name for region "
                     ^ Print.option_to_string Pure.show_region_group_id
@@ -2022,16 +2031,16 @@ let extract_trait_decl_register_names (ctx : extraction_ctx)
     (trait_decl : trait_decl) : extraction_ctx =
   (* Lookup the information if this is a builtin trait *)
   let open ExtractBuiltin in
-  let sname = name_to_simple_name trait_decl.name in
   let builtin_info =
-    SimpleNameMap.find_opt sname (builtin_trait_decls_map ())
+    match_name_find_opt ctx.trans_ctx trait_decl.llbc_name
+      (builtin_trait_decls_map ())
   in
   let ctx =
     let trait_name, trait_constructor =
       match builtin_info with
       | None ->
-          ( ctx.fmt.trait_decl_name trait_decl,
-            ctx.fmt.trait_decl_constructor trait_decl )
+          ( ctx_compute_trait_decl_name ctx trait_decl,
+            ctx_compute_trait_decl_constructor ctx trait_decl )
       | Some info -> (info.extract_name, info.constructor)
     in
     let ctx = ctx_add (TraitDeclId trait_decl.def_id) trait_name ctx in
@@ -2059,9 +2068,14 @@ let extract_trait_impl_register_names (ctx : extraction_ctx)
   (* Check if the trait implementation is builtin *)
   let builtin_info =
     let open ExtractBuiltin in
-    let type_sname = name_to_simple_name trait_impl.name in
-    let trait_sname = name_to_simple_name trait_decl.name in
-    SimpleNamePairMap.find_opt (type_sname, trait_sname)
+    (* Lookup the original Rust impl to retrieve the original trait ref (we
+       use it to derive the name)*)
+    let trait_impl =
+      TraitImplId.Map.find trait_impl.def_id ctx.crate.trait_impls
+    in
+    let decl_ref = trait_impl.impl_trait in
+    match_name_with_generics_find_opt ctx.trans_ctx trait_decl.llbc_name
+      decl_ref.decl_generics
       (builtin_trait_impls_map ())
   in
   (* Register some builtin information (if necessary) *)
@@ -2090,7 +2104,7 @@ let extract_trait_impl_register_names (ctx : extraction_ctx)
   (* Compute the name *)
   let name =
     match builtin_info with
-    | None -> ctx.fmt.trait_impl_name trait_decl trait_impl
+    | None -> ctx_compute_trait_impl_name ctx trait_decl trait_impl
     | Some name -> name
   in
   ctx_add (TraitImplId trait_impl.def_id) name ctx
@@ -2154,8 +2168,14 @@ let extract_trait_decl_method_items (ctx : extraction_ctx) (fmt : F.formatter)
         generic_params_drop_prefix ~drop_trait_clauses decl.generics
           f.signature.generics
       in
+      (* Note that we do not filter the LLBC generic parameters.
+         This is ok because:
+         - we only use them to find meaningful names for the trait clauses
+         - we only generate trait clauses for the clauses we find in the
+           pure generics *)
       let ctx, type_params, cg_params, trait_clauses =
-        ctx_add_generic_params generics ctx
+        ctx_add_generic_params f.llbc_name f.signature.llbc_generics generics
+          ctx
       in
       let backend_uses_forall =
         match !backend with Coq | Lean -> true | FStar | HOL4 -> false
@@ -2184,8 +2204,9 @@ let extract_trait_decl (ctx : extraction_ctx) (fmt : F.formatter)
   (* Add a break before *)
   F.pp_print_break fmt 0 0;
   (* Print a comment to link the extracted type to its original rust definition *)
-  extract_comment fmt
-    [ "Trait declaration: [" ^ Print.name_to_string decl.name ^ "]" ];
+  extract_comment_with_span fmt
+    [ "Trait declaration: [" ^ name_to_string ctx decl.llbc_name ^ "]" ]
+    decl.meta.span;
   F.pp_print_break fmt 0 0;
   (* Open two outer boxes for the definition, so that whenever possible it gets printed on
      one line and indents are correct.
@@ -2202,7 +2223,7 @@ let extract_trait_decl (ctx : extraction_ctx) (fmt : F.formatter)
   (* Open the box for the name + generics *)
   F.pp_open_hovbox fmt ctx.indent_incr;
   let qualif =
-    Option.get (ctx.fmt.type_decl_kind_to_qualif SingleNonRec (Some Struct))
+    Option.get (type_decl_kind_to_qualif SingleNonRec (Some Struct))
   in
   (* When checking if the trait declaration is empty: we ignore the provided
      methods, because for now they are extracted separately *)
@@ -2218,7 +2239,7 @@ let extract_trait_decl (ctx : extraction_ctx) (fmt : F.formatter)
   (* Add the type and const generic params - note that we need those bindings only for the
    * body translation (they are not top-level) *)
   let ctx, type_params, cg_params, trait_clauses =
-    ctx_add_generic_params generics ctx
+    ctx_add_generic_params decl.llbc_name decl.llbc_generics generics ctx
   in
   extract_generic_params ctx fmt TypeDeclId.Set.empty generics type_params
     cg_params trait_clauses;
@@ -2437,8 +2458,17 @@ let extract_trait_impl_method_items (ctx : extraction_ctx) (fmt : F.formatter)
           { impl.generics with types = impl_types }
           f_generics
       in
-      (* Register and print the quantified generics *)
-      let ctx, f_tys, f_cgs, f_tcs = ctx_add_generic_params f_generics ctx in
+      (* Register and print the quantified generics.
+
+         Note that we do not filter the LLBC generic parameters.
+         This is ok because:
+         - we only use them to find meaningful names for the trait clauses
+         - we only generate trait clauses for the clauses we find in the
+           pure generics *)
+      let ctx, f_tys, f_cgs, f_tcs =
+        ctx_add_generic_params f.llbc_name f.signature.llbc_generics f_generics
+          ctx
+      in
       let use_forall = f_generics <> empty_generic_params in
       extract_generic_params ctx fmt TypeDeclId.Set.empty ~use_forall f_generics
         f_tys f_cgs f_tcs;
@@ -2466,14 +2496,15 @@ let extract_trait_impl_method_items (ctx : extraction_ctx) (fmt : F.formatter)
 (** Extract a trait implementation *)
 let extract_trait_impl (ctx : extraction_ctx) (fmt : F.formatter)
     (impl : trait_impl) : unit =
-  log#ldebug (lazy ("extract_trait_impl: " ^ Names.name_to_string impl.name));
+  log#ldebug (lazy ("extract_trait_impl: " ^ name_to_string ctx impl.llbc_name));
   (* Retrieve the impl name *)
   let impl_name = ctx_get_trait_impl impl.def_id ctx in
   (* Add a break before *)
   F.pp_print_break fmt 0 0;
   (* Print a comment to link the extracted type to its original rust definition *)
-  extract_comment fmt
-    [ "Trait implementation: [" ^ Print.name_to_string impl.name ^ "]" ];
+  extract_comment_with_span fmt
+    [ "Trait implementation: [" ^ name_to_string ctx impl.llbc_name ^ "]" ]
+    impl.meta.span;
   F.pp_print_break fmt 0 0;
 
   (* Open two outer boxes for the definition, so that whenever possible it gets printed on
@@ -2492,7 +2523,7 @@ let extract_trait_impl (ctx : extraction_ctx) (fmt : F.formatter)
   (* `let (....) : Trait ... =` *)
   (* Open the box for the name + generics *)
   F.pp_open_hovbox fmt ctx.indent_incr;
-  (match ctx.fmt.fun_decl_kind_to_qualif SingleNonRec with
+  (match fun_decl_kind_to_qualif SingleNonRec with
   | Some qualif ->
       F.pp_print_string fmt qualif;
       F.pp_print_space fmt ()
@@ -2503,7 +2534,7 @@ let extract_trait_impl (ctx : extraction_ctx) (fmt : F.formatter)
   (* Add the type and const generic params - note that we need those bindings only for the
    * body translation (they are not top-level) *)
   let ctx, type_params, cg_params, trait_clauses =
-    ctx_add_generic_params impl.generics ctx
+    ctx_add_generic_params impl.llbc_name impl.llbc_generics impl.generics ctx
   in
   let all_generics = (type_params, cg_params, trait_clauses) in
   extract_generic_params ctx fmt TypeDeclId.Set.empty impl.generics type_params
@@ -2640,7 +2671,7 @@ let extract_unit_test_if_unit_fun (ctx : extraction_ctx) (fmt : F.formatter)
     F.pp_print_break fmt 0 0;
     (* Print a comment *)
     extract_comment fmt
-      [ "Unit test for [" ^ Print.fun_name_to_string def.basename ^ "]" ];
+      [ "Unit test for [" ^ name_to_string ctx def.llbc_name ^ "]" ];
     F.pp_print_space fmt ();
     (* Open a box for the test *)
     F.pp_open_hovbox fmt ctx.indent_incr;
@@ -2662,7 +2693,7 @@ let extract_unit_test_if_unit_fun (ctx : extraction_ctx) (fmt : F.formatter)
         F.pp_print_space fmt ();
         F.pp_print_string fmt "=";
         F.pp_print_space fmt ();
-        let success = ctx_get_variant (Assumed Result) result_return_id ctx in
+        let success = ctx_get_variant (TAssumed TResult) result_return_id ctx in
         F.pp_print_string fmt (success ^ " ())")
     | Coq ->
         F.pp_print_string fmt "Check";
@@ -2691,7 +2722,7 @@ let extract_unit_test_if_unit_fun (ctx : extraction_ctx) (fmt : F.formatter)
         F.pp_print_space fmt ();
         F.pp_print_string fmt "==";
         F.pp_print_space fmt ();
-        let success = ctx_get_variant (Assumed Result) result_return_id ctx in
+        let success = ctx_get_variant (TAssumed TResult) result_return_id ctx in
         F.pp_print_string fmt ("." ^ success ^ " ())")
     | HOL4 ->
         F.pp_print_string fmt "val _ = assert_return (";
diff --git a/compiler/ExtractBase.ml b/compiler/ExtractBase.ml
index 31b1a447..c6158847 100644
--- a/compiler/ExtractBase.ml
+++ b/compiler/ExtractBase.ml
@@ -1,14 +1,15 @@
 (** Define base utilities for the extraction *)
 
+open Contexts
 open Pure
-open TranslateCore
-module C = Contexts
-module RegionVarId = T.RegionVarId
+open StringUtils
+open Config
 module F = Format
 open ExtractBuiltin
+open TranslateCore
 
 (** The local logger *)
-let log = L.extract_log
+let log = Logging.extract_log
 
 type region_group_info = {
   id : RegionGroupId.id;
@@ -25,11 +26,6 @@ type region_group_info = {
 module StringSet = Collections.StringSet
 module StringMap = Collections.StringMap
 
-type name = Names.name
-type type_name = Names.type_name
-type global_name = Names.global_name
-type fun_name = Names.fun_name
-
 (** Characterizes a declaration.
 
     Is in particular useful to derive the proper keywords to introduce the
@@ -115,225 +111,6 @@ let decl_is_not_last_from_group (kind : decl_kind) : bool =
 
 type type_decl_kind = Enum | Struct [@@deriving show]
 
-(* TODO: this should be a module we give to a functor! *)
-
-(** A formatter's role is twofold:
-    1. Come up with name suggestions.
-    For instance, provided some information about a function (its basename,
-    information about the region group, etc.) it should come up with an
-    appropriate name for the forward/backward function.
-
-    It can of course apply many transformations, like changing to camel case/
-    snake case, adding prefixes/suffixes, etc.
-
-    2. Format some specific terms, like constants.
-
-    TODO: unclear that this is useful now that all the backends are so much
-    entangled in Extract.ml
- *)
-type formatter = {
-  bool_name : string;
-  char_name : string;
-  int_name : integer_type -> string;
-  str_name : string;
-  type_decl_kind_to_qualif :
-    decl_kind -> type_decl_kind option -> string option;
-      (** Compute the qualified for a type definition/declaration.
-
-          For instance: "type", "and", etc.
-
-          Remark: can return [None] for some backends like HOL4.
-       *)
-  fun_decl_kind_to_qualif : decl_kind -> string option;
-      (** Compute the qualified for a function definition/declaration.
-
-          For instance: "let", "let rec", "and", etc.
-
-          Remark: can return [None] for some backends like HOL4.
-       *)
-  field_name : name -> FieldId.id -> string option -> string;
-      (** Inputs:
-          - type name
-          - field id
-          - field name
-
-          Note that fields don't always have names, but we still need to
-          generate some names if we want to extract the structures to records...
-          We might want to extract such structures to tuples, later, but field
-          access then causes trouble because not all provers accept syntax like
-          [x.3] where [x] is a tuple.
-       *)
-  variant_name : name -> string -> string;
-      (** Inputs:
-          - type name
-          - variant name
-       *)
-  struct_constructor : name -> string;
-      (** Structure constructors are used when constructing structure values.
-
-          For instance, in F*:
-          {[
-            type pair = { x : nat; y : nat }
-            let p : pair = Mkpair 0 1
-          ]}
-
-          Inputs:
-          - type name
-       *)
-  type_name : type_name -> string;
-      (** Provided a basename, compute a type name. *)
-  global_name : global_name -> string;
-      (** Provided a basename, compute a global name. *)
-  fun_name :
-    fun_name ->
-    int ->
-    LoopId.id option ->
-    int ->
-    region_group_info option ->
-    bool * int ->
-    string;
-      (** Compute the name of a regular (non-assumed) function.
-
-          Inputs:
-          - function basename (TODO: shouldn't appear for assumed functions?...)
-          - number of loops in the function (useful to check if we need to use
-            indices to derive unique names for the loops for instance - if there is
-            exactly one loop, we don't need to use indices)
-          - loop id (if pertinent)
-          - number of region groups
-          - region group information in case of a backward function
-            ([None] if forward function)
-          - pair:
-            - do we generate the forward function (it may have been filtered)?
-            - the number of *extracted backward functions* (same comment as for
-              the number of loops)
-              The number of extracted backward functions if not necessarily
-              equal to the number of region groups, because we may have
-              filtered some of them.
-          TODO: use the fun id for the assumed functions.
-       *)
-  termination_measure_name :
-    A.FunDeclId.id -> fun_name -> int -> LoopId.id option -> string;
-      (** Generates the name of the termination measure used to prove/reason about
-          termination. The generated code uses this clause where needed,
-          but its body must be defined by the user.
-
-          F* and Lean only.
-
-          Inputs:
-          - function id: this is especially useful to identify whether the
-            function is an assumed function or a local function
-          - function basename
-          - the number of loops in the parent function. This is used for
-            the same purpose as in {!field:fun_name}.
-          - loop identifier, if this is for a loop
-       *)
-  decreases_proof_name :
-    A.FunDeclId.id -> fun_name -> int -> LoopId.id option -> string;
-      (** Generates the name of the proof used to prove/reason about
-          termination. The generated code uses this clause where needed,
-          but its body must be defined by the user.
-
-          Lean only.
-
-          Inputs:
-          - function id: this is especially useful to identify whether the
-            function is an assumed function or a local function
-          - function basename
-          - the number of loops in the parent function. This is used for
-            the same purpose as in {!field:fun_name}.
-          - loop identifier, if this is for a loop
-       *)
-  trait_decl_name : trait_decl -> string;
-  trait_impl_name : trait_decl -> trait_impl -> string;
-  trait_decl_constructor : trait_decl -> string;
-  trait_parent_clause_name : trait_decl -> trait_clause -> string;
-  trait_const_name : trait_decl -> string -> string;
-  trait_type_name : trait_decl -> string -> string;
-  trait_method_name : trait_decl -> string -> string;
-  trait_type_clause_name : trait_decl -> string -> trait_clause -> string;
-  var_basename : StringSet.t -> string option -> ty -> string;
-      (** Generates a variable basename.
-
-          Inputs:
-          - the set of names used in the context so far
-          - the basename we got from the symbolic execution, if we have one
-          - the type of the variable (can be useful for heuristics, in order
-            not to always use "x" for instance, whenever naming anonymous
-            variables)
-
-          Note that once the formatter generated a basename, we add an index
-          if necessary to prevent name clashes: the burden of name clashes checks
-          is thus on the caller's side.
-       *)
-  type_var_basename : StringSet.t -> string -> string;
-      (** Generates a type variable basename. *)
-  const_generic_var_basename : StringSet.t -> string -> string;
-      (** Generates a const generic variable basename. *)
-  trait_self_clause_basename : string;
-  trait_clause_basename : StringSet.t -> trait_clause -> string;
-      (** Return a base name for a trait clause. We might add a suffix to prevent
-          collisions.
-
-          In the traduction we explicitely manipulate the trait clause instances,
-          that is we introduce one input variable for each trait clause.
-       *)
-  append_index : string -> int -> string;
-      (** Appends an index to a name - we use this to generate unique
-          names: when doing so, the role of the formatter is just to concatenate
-          indices to names, the responsability of finding a proper index is
-          delegated to helper functions.
-       *)
-  extract_literal : F.formatter -> bool -> literal -> unit;
-      (** Format a constant value.
-
-          Inputs:
-          - formatter
-          - [inside]: if [true], the value should be wrapped in parentheses
-            if it is made of an application (ex.: [U32 3])
-          - the constant value
-       *)
-  extract_unop :
-    (bool -> texpression -> unit) ->
-    F.formatter ->
-    bool ->
-    unop ->
-    texpression ->
-    unit;
-      (** Format a unary operation
-
-          Inputs:
-          - a formatter for expressions (called on the argument of the unop)
-          - extraction context (see below)
-          - formatter
-          - expression formatter
-          - [inside]
-          - unop
-          - argument
-       *)
-  extract_binop :
-    (bool -> texpression -> unit) ->
-    F.formatter ->
-    bool ->
-    E.binop ->
-    integer_type ->
-    texpression ->
-    texpression ->
-    unit;
-      (** Format a binary operation
-
-          Inputs:
-          - a formatter for expressions (called on the arguments of the binop)
-          - extraction context (see below)
-          - formatter
-          - expression formatter
-          - [inside]
-          - binop
-          - argument 0
-          - argument 1
-       *)
-}
-
 (** We use identifiers to look for name clashes *)
 type id =
   | GlobalId of A.GlobalDeclId.id
@@ -596,6 +373,152 @@ type names_maps = {
        *)
 }
 
+(** Return [true] if we are strict on collisions for this id (i.e., we forbid
+    collisions even with the ids in the unsafe names map) *)
+let strict_collisions (id : id) : bool =
+  match id with UnknownId | TypeId _ -> true | _ -> false
+
+(** We might not check for collisions for some specific ids (ex.: field names) *)
+let allow_collisions (id : id) : bool =
+  match id with
+  | FieldId _ | TraitItemClauseId _ | TraitParentClauseId _ | TraitItemId _
+  | TraitMethodId _ ->
+      !Config.record_fields_short_names
+  | FunId (Pure _ | FromLlbc (FunId (FAssumed _), _, _)) ->
+      (* We map several assumed functions to the same id *)
+      true
+  | _ -> false
+
+(** The [id_to_string] function to print nice debugging messages if there are
+    collisions *)
+let names_maps_add (id_to_string : id -> string) (id : id) (name : string)
+    (nm : names_maps) : names_maps =
+  (* We do not use the same name map if we allow/disallow collisions.
+     We notably use it for field names: some backends like Lean can use the
+     type information to disambiguate field projections.
+
+     Remark: we still need to check that those "unsafe" ids don't collide with
+     the ids that we mark as "strict on collision".
+
+     For instance, we don't allow naming a field "let". We enforce this by
+     not checking collision between ids for which we permit collisions (ex.:
+     between fields), but still checking collisions between those ids and the
+     others (ex.: fields and keywords).
+  *)
+  if allow_collisions id then (
+    (* Check with the ids which are considered to be strict on collisions *)
+    names_map_check_collision id_to_string id name nm.strict_names_map;
+    {
+      nm with
+      unsafe_names_map = unsafe_names_map_add id name nm.unsafe_names_map;
+    })
+  else
+    (* Remark: if we are strict on collisions:
+       - we add the id to the strict collisions map
+       - we check that the id doesn't collide with the unsafe map
+       TODO: we might not check that:
+       - a user defined function doesn't collide with an assumed function
+       - two trait decl items don't collide with each other
+    *)
+    let strict_names_map =
+      if strict_collisions id then
+        names_map_add id_to_string id name nm.strict_names_map
+      else nm.strict_names_map
+    in
+    let names_map = names_map_add id_to_string id name nm.names_map in
+    { nm with strict_names_map; names_map }
+
+(** The [id_to_string] function to print nice debugging messages if there are
+    collisions *)
+let names_maps_get (id_to_string : id -> string) (id : id) (nm : names_maps) :
+    string =
+  (* We do not use the same name map if we allow/disallow collisions *)
+  let map_to_string (m : string IdMap.t) : string =
+    "[\n"
+    ^ String.concat ","
+        (List.map
+           (fun (id, n) -> "\n  " ^ id_to_string id ^ " -> " ^ n)
+           (IdMap.bindings m))
+    ^ "\n]"
+  in
+  if allow_collisions id then (
+    let m = nm.unsafe_names_map.id_to_name in
+    match IdMap.find_opt id m with
+    | Some s -> s
+    | None ->
+        let err =
+          "Could not find: " ^ id_to_string id ^ "\nNames map:\n"
+          ^ map_to_string m
+        in
+        log#serror err;
+        if !Config.fail_hard then raise (Failure err)
+        else "(%%%ERROR: unknown identifier\": " ^ id_to_string id ^ "\"%%%)")
+  else
+    let m = nm.names_map.id_to_name in
+    match IdMap.find_opt id m with
+    | Some s -> s
+    | None ->
+        let err =
+          "Could not find: " ^ id_to_string id ^ "\nNames map:\n"
+          ^ map_to_string m
+        in
+        log#serror err;
+        if !Config.fail_hard then raise (Failure err)
+        else "(ERROR: \"" ^ id_to_string id ^ "\")"
+
+type names_map_init = {
+  keywords : string list;
+  assumed_adts : (assumed_ty * string) list;
+  assumed_structs : (assumed_ty * string) list;
+  assumed_variants : (assumed_ty * VariantId.id * string) list;
+  assumed_llbc_functions :
+    (A.assumed_fun_id * RegionGroupId.id option * string) list;
+  assumed_pure_functions : (pure_assumed_fun_id * string) list;
+}
+
+let names_maps_add_assumed_type (id_to_string : id -> string) (id : assumed_ty)
+    (name : string) (nm : names_maps) : names_maps =
+  names_maps_add id_to_string (TypeId (TAssumed id)) name nm
+
+let names_maps_add_assumed_struct (id_to_string : id -> string)
+    (id : assumed_ty) (name : string) (nm : names_maps) : names_maps =
+  names_maps_add id_to_string (StructId (TAssumed id)) name nm
+
+let names_maps_add_assumed_variant (id_to_string : id -> string)
+    (id : assumed_ty) (variant_id : VariantId.id) (name : string)
+    (nm : names_maps) : names_maps =
+  names_maps_add id_to_string (VariantId (TAssumed id, variant_id)) name nm
+
+let names_maps_add_function (id_to_string : id -> string) (fid : fun_id)
+    (name : string) (nm : names_maps) : names_maps =
+  names_maps_add id_to_string (FunId fid) name nm
+
+let bool_name () = if !backend = Lean then "Bool" else "bool"
+let char_name () = if !backend = Lean then "Char" else "char"
+let str_name () = if !backend = Lean then "String" else "string"
+
+(** Small helper to compute the name of an int type *)
+let int_name (int_ty : integer_type) =
+  let isize, usize, i_format, u_format =
+    match !backend with
+    | FStar | Coq | HOL4 ->
+        ("isize", "usize", format_of_string "i%d", format_of_string "u%d")
+    | Lean -> ("Isize", "Usize", format_of_string "I%d", format_of_string "U%d")
+  in
+  match int_ty with
+  | Isize -> isize
+  | I8 -> Printf.sprintf i_format 8
+  | I16 -> Printf.sprintf i_format 16
+  | I32 -> Printf.sprintf i_format 32
+  | I64 -> Printf.sprintf i_format 64
+  | I128 -> Printf.sprintf i_format 128
+  | Usize -> usize
+  | U8 -> Printf.sprintf u_format 8
+  | U16 -> Printf.sprintf u_format 16
+  | U32 -> Printf.sprintf u_format 32
+  | U64 -> Printf.sprintf u_format 64
+  | U128 -> Printf.sprintf u_format 128
+
 (** Extraction context.
 
     Note that the extraction context contains information coming from the
@@ -607,7 +530,6 @@ type extraction_ctx = {
   crate : A.crate;
   trans_ctx : trans_ctx;
   names_maps : names_maps;
-  fmt : formatter;
   indent_incr : int;
       (** The indent increment we insert whenever we need to indent more *)
   use_dep_ite : bool;
@@ -654,72 +576,47 @@ type extraction_ctx = {
       (** Same as {!types_filter_type_args_map}, but for trait implementations *)
 }
 
+let extraction_ctx_to_fmt_env (ctx : extraction_ctx) : PrintPure.fmt_env =
+  TranslateCore.trans_ctx_to_pure_fmt_env ctx.trans_ctx
+
+let name_to_string (ctx : extraction_ctx) =
+  PrintPure.name_to_string (extraction_ctx_to_fmt_env ctx)
+
+let trait_decl_id_to_string (ctx : extraction_ctx) =
+  PrintPure.trait_decl_id_to_string (extraction_ctx_to_fmt_env ctx)
+
+let type_id_to_string (ctx : extraction_ctx) =
+  PrintPure.type_id_to_string (extraction_ctx_to_fmt_env ctx)
+
+let global_decl_id_to_string (ctx : extraction_ctx) =
+  PrintPure.global_decl_id_to_string (extraction_ctx_to_fmt_env ctx)
+
+let llbc_fun_id_to_string (ctx : extraction_ctx) =
+  PrintPure.llbc_fun_id_to_string (extraction_ctx_to_fmt_env ctx)
+
+let fun_id_to_string (ctx : extraction_ctx) =
+  PrintPure.regular_fun_id_to_string (extraction_ctx_to_fmt_env ctx)
+
+let adt_variant_to_string (ctx : extraction_ctx) =
+  PrintPure.adt_variant_to_string (extraction_ctx_to_fmt_env ctx)
+
+let adt_field_to_string (ctx : extraction_ctx) =
+  PrintPure.adt_field_to_string (extraction_ctx_to_fmt_env ctx)
+
 (** Debugging function, used when communicating name collisions to the user,
     and also to print ids for internal debugging (in case of lookup miss for
     instance).
  *)
 let id_to_string (id : id) (ctx : extraction_ctx) : string =
-  let global_decls = ctx.trans_ctx.global_ctx.global_decls in
-  let fun_decls = ctx.trans_ctx.fun_ctx.fun_decls in
-  let type_decls = ctx.trans_ctx.type_ctx.type_decls in
-  let trait_decls = ctx.trans_ctx.trait_decls_ctx.trait_decls in
   let trait_decl_id_to_string (id : A.TraitDeclId.id) : string =
-    let trait_name =
-      Print.fun_name_to_string (A.TraitDeclId.Map.find id trait_decls).name
-    in
+    let trait_name = trait_decl_id_to_string ctx id in
     "trait_decl: " ^ trait_name ^ " (id: " ^ A.TraitDeclId.to_string id ^ ")"
   in
-  (* TODO: factorize the pretty-printing with what is in PrintPure *)
-  let get_type_name (id : type_id) : string =
-    match id with
-    | AdtId id ->
-        let def = TypeDeclId.Map.find id type_decls in
-        Print.name_to_string def.name
-    | Assumed aty -> show_assumed_ty aty
-    | Tuple -> raise (Failure "Unreachable")
-  in
   match id with
-  | GlobalId gid ->
-      let name = (A.GlobalDeclId.Map.find gid global_decls).name in
-      "global name: " ^ Print.global_name_to_string name
-  | FunId fid -> (
-      match fid with
-      | FromLlbc (fid, lp_id, rg_id) ->
-          let fun_name =
-            match fid with
-            | FunId (Regular fid) ->
-                Print.fun_name_to_string
-                  (A.FunDeclId.Map.find fid fun_decls).name
-            | FunId (Assumed aid) -> A.show_assumed_fun_id aid
-            | TraitMethod (trait_ref, method_name, _) ->
-                (* Shouldn't happen *)
-                if !Config.fail_hard then raise (Failure "Unexpected")
-                else
-                  "Trait method: decl: "
-                  ^ TraitDeclId.to_string trait_ref.trait_decl_ref.trait_decl_id
-                  ^ ", method_name: " ^ method_name
-          in
-
-          let lp_kind =
-            match lp_id with
-            | None -> ""
-            | Some lp_id -> "loop " ^ LoopId.to_string lp_id ^ ", "
-          in
-
-          let fwd_back_kind =
-            match rg_id with
-            | None -> "forward"
-            | Some rg_id -> "backward " ^ RegionGroupId.to_string rg_id
-          in
-          "fun name (" ^ lp_kind ^ fwd_back_kind ^ "): " ^ fun_name
-      | Pure fid -> PrintPure.pure_assumed_fun_id_to_string fid)
+  | GlobalId gid -> global_decl_id_to_string ctx gid
+  | FunId fid -> fun_id_to_string ctx fid
   | DecreasesProofId (fid, lid) ->
-      let fun_name =
-        match fid with
-        | Regular fid ->
-            Print.fun_name_to_string (A.FunDeclId.Map.find fid fun_decls).name
-        | Assumed aid -> A.show_assumed_fun_id aid
-      in
+      let fun_name = llbc_fun_id_to_string ctx fid in
       let loop =
         match lid with
         | None -> ""
@@ -727,72 +624,20 @@ let id_to_string (id : id) (ctx : extraction_ctx) : string =
       in
       "decreases proof for function: " ^ fun_name ^ loop
   | TerminationMeasureId (fid, lid) ->
-      let fun_name =
-        match fid with
-        | Regular fid ->
-            Print.fun_name_to_string (A.FunDeclId.Map.find fid fun_decls).name
-        | Assumed aid -> A.show_assumed_fun_id aid
-      in
+      let fun_name = llbc_fun_id_to_string ctx fid in
       let loop =
         match lid with
         | None -> ""
         | Some lid -> ", loop: " ^ LoopId.to_string lid
       in
       "termination measure for function: " ^ fun_name ^ loop
-  | TypeId id -> "type name: " ^ get_type_name id
-  | StructId id -> "struct constructor of: " ^ get_type_name id
+  | TypeId id -> "type name: " ^ type_id_to_string ctx id
+  | StructId id -> "struct constructor of: " ^ type_id_to_string ctx id
   | VariantId (id, variant_id) ->
-      let variant_name =
-        match id with
-        | Tuple -> raise (Failure "Unreachable")
-        | Assumed Result ->
-            if variant_id = result_return_id then "@result::Return"
-            else if variant_id = result_fail_id then "@result::Fail"
-            else raise (Failure "Unreachable")
-        | Assumed Error ->
-            if variant_id = error_failure_id then "@error::Failure"
-            else if variant_id = error_out_of_fuel_id then "@error::OutOfFuel"
-            else raise (Failure "Unreachable")
-        | Assumed Fuel ->
-            if variant_id = fuel_zero_id then "@fuel::0"
-            else if variant_id = fuel_succ_id then "@fuel::Succ"
-            else raise (Failure "Unreachable")
-        | Assumed (State | Array | Slice | Str | RawPtr _) ->
-            raise
-              (Failure
-                 ("Unreachable: variant id ("
-                 ^ VariantId.to_string variant_id
-                 ^ ") for " ^ show_type_id id))
-        | AdtId id -> (
-            let def = TypeDeclId.Map.find id type_decls in
-            match def.kind with
-            | Struct _ | Opaque -> raise (Failure "Unreachable")
-            | Enum variants ->
-                let variant = VariantId.nth variants variant_id in
-                Print.name_to_string def.name ^ "::" ^ variant.variant_name)
-      in
+      let variant_name = adt_variant_to_string ctx id (Some variant_id) in
       "variant name: " ^ variant_name
   | FieldId (id, field_id) ->
-      let field_name =
-        match id with
-        | Tuple -> raise (Failure "Unreachable")
-        | Assumed
-            (State | Result | Error | Fuel | Array | Slice | Str | RawPtr _) ->
-            (* We can't directly have access to the fields of those types *)
-            raise (Failure "Unreachable")
-        | AdtId id -> (
-            let def = TypeDeclId.Map.find id type_decls in
-            match def.kind with
-            | Enum _ | Opaque -> raise (Failure "Unreachable")
-            | Struct fields ->
-                let field = FieldId.nth fields field_id in
-                let field_name =
-                  match field.field_name with
-                  | None -> FieldId.to_string field_id
-                  | Some name -> name
-                in
-                Print.name_to_string def.name ^ "." ^ field_name)
-      in
+      let field_name = adt_field_to_string ctx id field_id in
       "field name: " ^ field_name
   | UnknownId -> "keyword"
   | TypeVarId id -> "type_var_id: " ^ TypeVarId.to_string id
@@ -824,125 +669,15 @@ let id_to_string (id : id) (ctx : extraction_ctx) : string =
       ^ ", method name (" ^ fwd_back_kind ^ "): " ^ fun_name
   | TraitSelfClauseId -> "trait_self_clause"
 
-(** Return [true] if we are strict on collisions for this id (i.e., we forbid
-    collisions even with the ids in the unsafe names map) *)
-let strict_collisions (id : id) : bool =
-  match id with UnknownId | TypeId _ -> true | _ -> false
-
-(** We might not check for collisions for some specific ids (ex.: field names) *)
-let allow_collisions (id : id) : bool =
-  match id with
-  | FieldId _ | TraitItemClauseId _ | TraitParentClauseId _ | TraitItemId _
-  | TraitMethodId _ ->
-      !Config.record_fields_short_names
-  | FunId (Pure _ | FromLlbc (FunId (Assumed _), _, _)) ->
-      (* We map several assumed functions to the same id *)
-      true
-  | _ -> false
-
-(** The [id_to_string] function to print nice debugging messages if there are
-    collisions *)
-let names_maps_add (id_to_string : id -> string) (id : id) (name : string)
-    (nm : names_maps) : names_maps =
-  (* We do not use the same name map if we allow/disallow collisions.
-     We notably use it for field names: some backends like Lean can use the
-     type information to disambiguate field projections.
-
-     Remark: we still need to check that those "unsafe" ids don't collide with
-     the ids that we mark as "strict on collision".
-
-     For instance, we don't allow naming a field "let". We enforce this by
-     not checking collision between ids for which we permit collisions (ex.:
-     between fields), but still checking collisions between those ids and the
-     others (ex.: fields and keywords).
-  *)
-  if allow_collisions id then (
-    (* Check with the ids which are considered to be strict on collisions *)
-    names_map_check_collision id_to_string id name nm.strict_names_map;
-    {
-      nm with
-      unsafe_names_map = unsafe_names_map_add id name nm.unsafe_names_map;
-    })
-  else
-    (* Remark: if we are strict on collisions:
-       - we add the id to the strict collisions map
-       - we check that the id doesn't collide with the unsafe map
-       TODO: we might not check that:
-       - a user defined function doesn't collide with an assumed function
-       - two trait decl items don't collide with each other
-    *)
-    let strict_names_map =
-      if strict_collisions id then
-        names_map_add id_to_string id name nm.strict_names_map
-      else nm.strict_names_map
-    in
-    let names_map = names_map_add id_to_string id name nm.names_map in
-    { nm with strict_names_map; names_map }
-
 let ctx_add (id : id) (name : string) (ctx : extraction_ctx) : extraction_ctx =
   let id_to_string (id : id) : string = id_to_string id ctx in
   let names_maps = names_maps_add id_to_string id name ctx.names_maps in
   { ctx with names_maps }
 
-(** The [id_to_string] function to print nice debugging messages if there are
-    collisions *)
-let names_maps_get (id_to_string : id -> string) (id : id) (nm : names_maps) :
-    string =
-  (* We do not use the same name map if we allow/disallow collisions *)
-  let map_to_string (m : string IdMap.t) : string =
-    "[\n"
-    ^ String.concat ","
-        (List.map
-           (fun (id, n) -> "\n  " ^ id_to_string id ^ " -> " ^ n)
-           (IdMap.bindings m))
-    ^ "\n]"
-  in
-  if allow_collisions id then (
-    let m = nm.unsafe_names_map.id_to_name in
-    match IdMap.find_opt id m with
-    | Some s -> s
-    | None ->
-        let err =
-          "Could not find: " ^ id_to_string id ^ "\nNames map:\n"
-          ^ map_to_string m
-        in
-        log#serror err;
-        if !Config.fail_hard then raise (Failure err)
-        else "(%%%ERROR: unknown identifier\": " ^ id_to_string id ^ "\"%%%)")
-  else
-    let m = nm.names_map.id_to_name in
-    match IdMap.find_opt id m with
-    | Some s -> s
-    | None ->
-        let err =
-          "Could not find: " ^ id_to_string id ^ "\nNames map:\n"
-          ^ map_to_string m
-        in
-        log#serror err;
-        if !Config.fail_hard then raise (Failure err)
-        else "(ERROR: \"" ^ id_to_string id ^ "\")"
-
 let ctx_get (id : id) (ctx : extraction_ctx) : string =
   let id_to_string (id : id) : string = id_to_string id ctx in
   names_maps_get id_to_string id ctx.names_maps
 
-let names_maps_add_assumed_type (id_to_string : id -> string) (id : assumed_ty)
-    (name : string) (nm : names_maps) : names_maps =
-  names_maps_add id_to_string (TypeId (Assumed id)) name nm
-
-let names_maps_add_assumed_struct (id_to_string : id -> string)
-    (id : assumed_ty) (name : string) (nm : names_maps) : names_maps =
-  names_maps_add id_to_string (StructId (Assumed id)) name nm
-
-let names_maps_add_assumed_variant (id_to_string : id -> string)
-    (id : assumed_ty) (variant_id : VariantId.id) (name : string)
-    (nm : names_maps) : names_maps =
-  names_maps_add id_to_string (VariantId (Assumed id, variant_id)) name nm
-
-let names_maps_add_function (id_to_string : id -> string) (fid : fun_id)
-    (name : string) (nm : names_maps) : names_maps =
-  names_maps_add id_to_string (FunId fid) name nm
-
 let ctx_get_global (id : A.GlobalDeclId.id) (ctx : extraction_ctx) : string =
   ctx_get (GlobalId id) ctx
 
@@ -951,17 +686,17 @@ let ctx_get_function (id : fun_id) (ctx : extraction_ctx) : string =
 
 let ctx_get_local_function (id : A.FunDeclId.id) (lp : LoopId.id option)
     (rg : RegionGroupId.id option) (ctx : extraction_ctx) : string =
-  ctx_get_function (FromLlbc (FunId (Regular id), lp, rg)) ctx
+  ctx_get_function (FromLlbc (FunId (FRegular id), lp, rg)) ctx
 
 let ctx_get_type (id : type_id) (ctx : extraction_ctx) : string =
-  assert (id <> Tuple);
+  assert (id <> TTuple);
   ctx_get (TypeId id) ctx
 
 let ctx_get_local_type (id : TypeDeclId.id) (ctx : extraction_ctx) : string =
-  ctx_get_type (AdtId id) ctx
+  ctx_get_type (TAdtId id) ctx
 
 let ctx_get_assumed_type (id : assumed_ty) (ctx : extraction_ctx) : string =
-  ctx_get_type (Assumed id) ctx
+  ctx_get_type (TAssumed id) ctx
 
 let ctx_get_trait_constructor (id : trait_decl_id) (ctx : extraction_ctx) :
     string =
@@ -1027,21 +762,1043 @@ let ctx_get_variant (def_id : type_id) (variant_id : VariantId.id)
 
 let ctx_get_decreases_proof (def_id : A.FunDeclId.id)
     (loop_id : LoopId.id option) (ctx : extraction_ctx) : string =
-  ctx_get (DecreasesProofId (Regular def_id, loop_id)) ctx
+  ctx_get (DecreasesProofId (FRegular def_id, loop_id)) ctx
 
 let ctx_get_termination_measure (def_id : A.FunDeclId.id)
     (loop_id : LoopId.id option) (ctx : extraction_ctx) : string =
-  ctx_get (TerminationMeasureId (Regular def_id, loop_id)) ctx
+  ctx_get (TerminationMeasureId (FRegular def_id, loop_id)) ctx
+
+(** Small helper to compute the name of a unary operation *)
+let unop_name (unop : unop) : string =
+  match unop with
+  | Not -> (
+      match !backend with FStar | Lean -> "not" | Coq -> "negb" | HOL4 -> "~")
+  | Neg (int_ty : integer_type) -> (
+      match !backend with Lean -> "-" | _ -> int_name int_ty ^ "_neg")
+  | Cast _ ->
+      (* We never directly use the unop name in this case *)
+      raise (Failure "Unsupported")
+
+(** Small helper to compute the name of a binary operation (note that many
+    binary operations like "less than" are extracted to primitive operations,
+    like [<]).
+ *)
+let named_binop_name (binop : E.binop) (int_ty : integer_type) : string =
+  let binop =
+    match binop with
+    | Div -> "div"
+    | Rem -> "rem"
+    | Add -> "add"
+    | Sub -> "sub"
+    | Mul -> "mul"
+    | Lt -> "lt"
+    | Le -> "le"
+    | Ge -> "ge"
+    | Gt -> "gt"
+    | BitXor -> "xor"
+    | BitAnd -> "and"
+    | BitOr -> "or"
+    | Shl -> "lsl"
+    | Shr ->
+        "asr"
+        (* NOTE: make sure arithmetic shift right is implemented, i.e. OCaml's asr operator, not lsr *)
+    | _ -> raise (Failure "Unreachable")
+  in
+  (* Remark: the Lean case is actually not used *)
+  match !backend with
+  | Lean -> int_name int_ty ^ "." ^ binop
+  | FStar | Coq | HOL4 -> int_name int_ty ^ "_" ^ binop
+
+(** A list of keywords/identifiers used by the backend and with which we
+    want to check collision.
+
+    Remark: this is useful mostly to look for collisions when generating
+    names for *variables*.
+ *)
+let keywords () =
+  let named_unops =
+    unop_name Not
+    :: List.map (fun it -> unop_name (Neg it)) T.all_signed_int_types
+  in
+  let named_binops = [ E.Div; Rem; Add; Sub; Mul ] in
+  let named_binops =
+    List.concat_map
+      (fun bn -> List.map (fun it -> named_binop_name bn it) T.all_int_types)
+      named_binops
+  in
+  let misc =
+    match !backend with
+    | FStar ->
+        [
+          "assert";
+          "assert_norm";
+          "assume";
+          "else";
+          "fun";
+          "fn";
+          "FStar";
+          "FStar.Mul";
+          "if";
+          "in";
+          "include";
+          "int";
+          "let";
+          "list";
+          "match";
+          "open";
+          "rec";
+          "scalar_cast";
+          "then";
+          "type";
+          "Type0";
+          "Type";
+          "unit";
+          "val";
+          "with";
+        ]
+    | Coq ->
+        [
+          "assert";
+          "Arguments";
+          "Axiom";
+          "char_of_byte";
+          "Check";
+          "Declare";
+          "Definition";
+          "else";
+          "End";
+          "fun";
+          "Fixpoint";
+          "if";
+          "in";
+          "int";
+          "Inductive";
+          "Import";
+          "let";
+          "Lemma";
+          "match";
+          "Module";
+          "not";
+          "Notation";
+          "Proof";
+          "Qed";
+          "rec";
+          "Record";
+          "Require";
+          "Scope";
+          "Search";
+          "SearchPattern";
+          "Set";
+          "then";
+          (* [tt] is unit *)
+          "tt";
+          "type";
+          "Type";
+          "unit";
+          "with";
+        ]
+    | Lean ->
+        [
+          "by";
+          "class";
+          "decreasing_by";
+          "def";
+          "deriving";
+          "do";
+          "else";
+          "end";
+          "for";
+          "have";
+          "if";
+          "inductive";
+          "instance";
+          "import";
+          "let";
+          "macro";
+          "match";
+          "namespace";
+          "opaque";
+          "open";
+          "run_cmd";
+          "set_option";
+          "simp";
+          "structure";
+          "syntax";
+          "termination_by";
+          "then";
+          "Type";
+          "unsafe";
+          "where";
+          "with";
+          "opaque_defs";
+        ]
+    | HOL4 ->
+        [
+          "Axiom";
+          "case";
+          "Definition";
+          "else";
+          "End";
+          "fix";
+          "fix_exec";
+          "fn";
+          "fun";
+          "if";
+          "in";
+          "int";
+          "Inductive";
+          "let";
+          "of";
+          "Proof";
+          "QED";
+          "then";
+          "Theorem";
+        ]
+  in
+  List.concat [ named_unops; named_binops; misc ]
+
+let assumed_adts () : (assumed_ty * string) list =
+  match !backend with
+  | Lean ->
+      [
+        (TState, "State");
+        (TResult, "Result");
+        (TError, "Error");
+        (TFuel, "Nat");
+        (TArray, "Array");
+        (TSlice, "Slice");
+        (TStr, "Str");
+        (TRawPtr Mut, "MutRawPtr");
+        (TRawPtr Const, "ConstRawPtr");
+      ]
+  | Coq | FStar | HOL4 ->
+      [
+        (TState, "state");
+        (TResult, "result");
+        (TError, "error");
+        (TFuel, if !backend = HOL4 then "num" else "nat");
+        (TArray, "array");
+        (TSlice, "slice");
+        (TStr, "str");
+        (TRawPtr Mut, "mut_raw_ptr");
+        (TRawPtr Const, "const_raw_ptr");
+      ]
+
+let assumed_struct_constructors () : (assumed_ty * string) list =
+  match !backend with
+  | Lean -> [ (TArray, "Array.make") ]
+  | Coq -> [ (TArray, "mk_array") ]
+  | FStar -> [ (TArray, "mk_array") ]
+  | HOL4 -> [ (TArray, "mk_array") ]
+
+let assumed_variants () : (assumed_ty * VariantId.id * string) list =
+  match !backend with
+  | FStar ->
+      [
+        (TResult, result_return_id, "Return");
+        (TResult, result_fail_id, "Fail");
+        (TError, error_failure_id, "Failure");
+        (TError, error_out_of_fuel_id, "OutOfFuel");
+        (* No Fuel::Zero on purpose *)
+        (* No Fuel::Succ on purpose *)
+      ]
+  | Coq ->
+      [
+        (TResult, result_return_id, "Return");
+        (TResult, result_fail_id, "Fail_");
+        (TError, error_failure_id, "Failure");
+        (TError, error_out_of_fuel_id, "OutOfFuel");
+        (TFuel, fuel_zero_id, "O");
+        (TFuel, fuel_succ_id, "S");
+      ]
+  | Lean ->
+      [
+        (TResult, result_return_id, "ret");
+        (TResult, result_fail_id, "fail");
+        (TError, error_failure_id, "panic");
+        (* No Fuel::Zero on purpose *)
+        (* No Fuel::Succ on purpose *)
+      ]
+  | HOL4 ->
+      [
+        (TResult, result_return_id, "Return");
+        (TResult, result_fail_id, "Fail");
+        (TError, error_failure_id, "Failure");
+        (* No Fuel::Zero on purpose *)
+        (* No Fuel::Succ on purpose *)
+      ]
+
+let assumed_llbc_functions () :
+    (A.assumed_fun_id * T.RegionGroupId.id option * string) list =
+  let rg0 = Some T.RegionGroupId.zero in
+  match !backend with
+  | FStar | Coq | HOL4 ->
+      [
+        (ArrayIndexShared, None, "array_index_usize");
+        (ArrayIndexMut, None, "array_index_usize");
+        (ArrayIndexMut, rg0, "array_update_usize");
+        (ArrayToSliceShared, None, "array_to_slice");
+        (ArrayToSliceMut, None, "array_to_slice");
+        (ArrayToSliceMut, rg0, "array_from_slice");
+        (ArrayRepeat, None, "array_repeat");
+        (SliceIndexShared, None, "slice_index_usize");
+        (SliceIndexMut, None, "slice_index_usize");
+        (SliceIndexMut, rg0, "slice_update_usize");
+      ]
+  | Lean ->
+      [
+        (ArrayIndexShared, None, "Array.index_usize");
+        (ArrayIndexMut, None, "Array.index_usize");
+        (ArrayIndexMut, rg0, "Array.update_usize");
+        (ArrayToSliceShared, None, "Array.to_slice");
+        (ArrayToSliceMut, None, "Array.to_slice");
+        (ArrayToSliceMut, rg0, "Array.from_slice");
+        (ArrayRepeat, None, "Array.repeat");
+        (SliceIndexShared, None, "Slice.index_usize");
+        (SliceIndexMut, None, "Slice.index_usize");
+        (SliceIndexMut, rg0, "Slice.update_usize");
+      ]
+
+let assumed_pure_functions () : (pure_assumed_fun_id * string) list =
+  match !backend with
+  | FStar ->
+      [
+        (Return, "return");
+        (Fail, "fail");
+        (Assert, "massert");
+        (FuelDecrease, "decrease");
+        (FuelEqZero, "is_zero");
+      ]
+  | Coq ->
+      (* We don't provide [FuelDecrease] and [FuelEqZero] on purpose *)
+      [ (Return, "return_"); (Fail, "fail_"); (Assert, "massert") ]
+  | Lean ->
+      (* We don't provide [FuelDecrease] and [FuelEqZero] on purpose *)
+      [ (Return, "return"); (Fail, "fail_"); (Assert, "massert") ]
+  | HOL4 ->
+      (* We don't provide [FuelDecrease] and [FuelEqZero] on purpose *)
+      [ (Return, "return"); (Fail, "fail"); (Assert, "massert") ]
+
+let names_map_init () : names_map_init =
+  {
+    keywords = keywords ();
+    assumed_adts = assumed_adts ();
+    assumed_structs = assumed_struct_constructors ();
+    assumed_variants = assumed_variants ();
+    assumed_llbc_functions = assumed_llbc_functions ();
+    assumed_pure_functions = assumed_pure_functions ();
+  }
+
+(** Initialize names maps with a proper set of keywords/names coming from the
+    target language/prover. *)
+let initialize_names_maps () : names_maps =
+  let init = names_map_init () in
+  let int_names = List.map int_name T.all_int_types in
+  let keywords =
+    List.concat
+      [ [ bool_name (); char_name (); str_name () ]; int_names; init.keywords ]
+  in
+  let names_set = StringSet.empty in
+  let name_to_id = StringMap.empty in
+  (* We fist initialize [id_to_name] as empty, because the id of a keyword is [UnknownId].
+   * Also note that we don't need this mapping for keywords: we insert keywords only
+   * to check collisions. *)
+  let id_to_name = IdMap.empty in
+  let names_map = { id_to_name; name_to_id; names_set } in
+  let unsafe_names_map = empty_unsafe_names_map in
+  let strict_names_map = empty_names_map in
+  (* For debugging - we are creating bindings for assumed types and functions, so
+   * it is ok if we simply use the "show" function (those aren't simply identified
+   * by numbers) *)
+  let id_to_string = show_id in
+  (* Add the keywords as strict collisions *)
+  let strict_names_map =
+    List.fold_left
+      (fun nm name ->
+        (* There is duplication in the keywords so we don't check the collisions
+           while registering them (what is important is that there are no collisions
+           between keywords and user-defined identifiers) *)
+        names_map_add_unchecked UnknownId name nm)
+      strict_names_map keywords
+  in
+  let nm = { names_map; unsafe_names_map; strict_names_map } in
+  (* Then we add:
+   * - the assumed types
+   * - the assumed struct constructors
+   * - the assumed variants
+   * - the assumed functions
+   *)
+  let nm =
+    List.fold_left
+      (fun nm (type_id, name) ->
+        names_maps_add_assumed_type id_to_string type_id name nm)
+      nm init.assumed_adts
+  in
+  let nm =
+    List.fold_left
+      (fun nm (type_id, name) ->
+        names_maps_add_assumed_struct id_to_string type_id name nm)
+      nm init.assumed_structs
+  in
+  let nm =
+    List.fold_left
+      (fun nm (type_id, variant_id, name) ->
+        names_maps_add_assumed_variant id_to_string type_id variant_id name nm)
+      nm init.assumed_variants
+  in
+  let assumed_functions =
+    List.map
+      (fun (fid, rg, name) ->
+        (FromLlbc (Pure.FunId (FAssumed fid), None, rg), name))
+      init.assumed_llbc_functions
+    @ List.map (fun (fid, name) -> (Pure fid, name)) init.assumed_pure_functions
+  in
+  let nm =
+    List.fold_left
+      (fun nm (fid, name) -> names_maps_add_function id_to_string fid name nm)
+      nm assumed_functions
+  in
+  (* Return *)
+  nm
+
+(** Compute the qualified for a type definition/declaration.
+
+    For instance: "type", "and", etc.
+
+    Remark: can return [None] for some backends like HOL4.
+ *)
+let type_decl_kind_to_qualif (kind : decl_kind)
+    (type_kind : type_decl_kind option) : string option =
+  match !backend with
+  | FStar -> (
+      match kind with
+      | SingleNonRec -> Some "type"
+      | SingleRec -> Some "type"
+      | MutRecFirst -> Some "type"
+      | MutRecInner -> Some "and"
+      | MutRecLast -> Some "and"
+      | Assumed -> Some "assume type"
+      | Declared -> Some "val")
+  | Coq -> (
+      match (kind, type_kind) with
+      | SingleNonRec, Some Enum -> Some "Inductive"
+      | SingleNonRec, Some Struct -> Some "Record"
+      | (SingleRec | MutRecFirst), Some _ -> Some "Inductive"
+      | (MutRecInner | MutRecLast), Some _ ->
+          (* Coq doesn't support groups of mutually recursive definitions which mix
+           * records and inducties: we convert everything to records if this happens
+           *)
+          Some "with"
+      | (Assumed | Declared), None -> Some "Axiom"
+      | SingleNonRec, None ->
+          (* This is for traits *)
+          Some "Record"
+      | _ ->
+          raise
+            (Failure
+               ("Unexpected: (" ^ show_decl_kind kind ^ ", "
+               ^ Print.option_to_string show_type_decl_kind type_kind
+               ^ ")")))
+  | Lean -> (
+      match kind with
+      | SingleNonRec ->
+          if type_kind = Some Struct then Some "structure" else Some "inductive"
+      | SingleRec -> Some "inductive"
+      | MutRecFirst -> Some "inductive"
+      | MutRecInner -> Some "inductive"
+      | MutRecLast -> Some "inductive"
+      | Assumed -> Some "axiom"
+      | Declared -> Some "axiom")
+  | HOL4 -> None
+
+(** Compute the qualified for a function definition/declaration.
+
+    For instance: "let", "let rec", "and", etc.
+
+    Remark: can return [None] for some backends like HOL4.
+ *)
+let fun_decl_kind_to_qualif (kind : decl_kind) : string option =
+  match !backend with
+  | FStar -> (
+      match kind with
+      | SingleNonRec -> Some "let"
+      | SingleRec -> Some "let rec"
+      | MutRecFirst -> Some "let rec"
+      | MutRecInner -> Some "and"
+      | MutRecLast -> Some "and"
+      | Assumed -> Some "assume val"
+      | Declared -> Some "val")
+  | Coq -> (
+      match kind with
+      | SingleNonRec -> Some "Definition"
+      | SingleRec -> Some "Fixpoint"
+      | MutRecFirst -> Some "Fixpoint"
+      | MutRecInner -> Some "with"
+      | MutRecLast -> Some "with"
+      | Assumed -> Some "Axiom"
+      | Declared -> Some "Axiom")
+  | Lean -> (
+      match kind with
+      | SingleNonRec -> Some "def"
+      | SingleRec -> Some "divergent def"
+      | MutRecFirst -> Some "mutual divergent def"
+      | MutRecInner -> Some "divergent def"
+      | MutRecLast -> Some "divergent def"
+      | Assumed -> Some "axiom"
+      | Declared -> Some "axiom")
+  | HOL4 -> None
+
+(** The type of types.
+
+    TODO: move inside the formatter?
+ *)
+let type_keyword () =
+  match !backend with
+  | FStar -> "Type0"
+  | Coq | Lean -> "Type"
+  | HOL4 -> raise (Failure "Unexpected")
+
+(** Helper *)
+let name_last_elem_as_ident (n : llbc_name) : string =
+  match Collections.List.last n with
+  | PeIdent (s, _) -> s
+  | PeImpl _ -> raise (Failure "Unexpected")
+
+(** Helper
+
+    Prepare a name.
+    The first id elem is always the crate: if it is the local crate,
+    we remove it. We ignore disambiguators (there may be collisions, but we
+    check if there are).
+ *)
+let ctx_compute_simple_name (ctx : extraction_ctx) (name : llbc_name) :
+    string list =
+  (* Rmk.: initially we only filtered the disambiguators equal to 0 *)
+  match name with
+  | (PeIdent (crate, _) as id) :: name ->
+      let name = if crate = ctx.crate.name then name else id :: name in
+      name_to_simple_name ctx.trans_ctx name
+  | _ ->
+      raise
+        (Failure
+           ("Unexpected name shape: "
+           ^ TranslateCore.name_to_string ctx.trans_ctx name))
+
+(** Helper *)
+let ctx_compute_simple_type_name = ctx_compute_simple_name
+
+(** Helper *)
+let ctx_compute_type_name_no_suffix (ctx : extraction_ctx) (name : llbc_name) :
+    string =
+  flatten_name (ctx_compute_simple_type_name ctx name)
+
+(** Provided a basename, compute a type name. *)
+let ctx_compute_type_name (ctx : extraction_ctx) (name : llbc_name) =
+  let name = ctx_compute_type_name_no_suffix ctx name in
+  match !backend with
+  | FStar -> StringUtils.lowercase_first_letter (name ^ "_t")
+  | Coq | HOL4 -> name ^ "_t"
+  | Lean -> name
+
+(** Inputs:
+    - type name
+    - field id
+    - field name
+
+    Note that fields don't always have names, but we still need to
+    generate some names if we want to extract the structures to records...
+    We might want to extract such structures to tuples, later, but field
+    access then causes trouble because not all provers accept syntax like
+    [x.3] where [x] is a tuple.
+ *)
+let ctx_compute_field_name (ctx : extraction_ctx) (def_name : llbc_name)
+    (field_id : FieldId.id) (field_name : string option) : string =
+  let field_name_s =
+    match field_name with
+    | Some field_name -> field_name
+    | None ->
+        (* TODO: extract structs with no field names to tuples *)
+        FieldId.to_string field_id
+  in
+  if !Config.record_fields_short_names then
+    if field_name = None then (* TODO: this is a bit ugly *)
+      "_" ^ field_name_s
+    else field_name_s
+  else
+    let def_name =
+      ctx_compute_type_name_no_suffix ctx def_name ^ "_" ^ field_name_s
+    in
+    match !backend with
+    | Lean | HOL4 -> def_name
+    | Coq | FStar -> StringUtils.lowercase_first_letter def_name
+
+(** Inputs:
+    - type name
+    - variant name
+ *)
+let ctx_compute_variant_name (ctx : extraction_ctx) (def_name : llbc_name)
+    (variant : string) : string =
+  match !backend with
+  | FStar | Coq | HOL4 ->
+      let variant = to_camel_case variant in
+      if !variant_concatenate_type_name then
+        StringUtils.capitalize_first_letter
+          (ctx_compute_type_name_no_suffix ctx def_name ^ "_" ^ variant)
+      else variant
+  | Lean -> variant
+
+(** Structure constructors are used when constructing structure values.
+
+    For instance, in F*:
+    {[
+      type pair = { x : nat; y : nat }
+      let p : pair = Mkpair 0 1
+    ]}
+
+    Inputs:
+    - type name
+*)
+let ctx_compute_struct_constructor (ctx : extraction_ctx) (basename : llbc_name)
+    : string =
+  let tname = ctx_compute_type_name ctx basename in
+  ExtractBuiltin.mk_struct_constructor tname
+
+let ctx_compute_fun_name_no_suffix (ctx : extraction_ctx) (fname : llbc_name) :
+    string =
+  let fname = ctx_compute_simple_name ctx fname in
+  (* TODO: don't convert to snake case for Coq, HOL4, F* *)
+  let fname = flatten_name fname in
+  match !backend with
+  | FStar | Coq | HOL4 -> StringUtils.lowercase_first_letter fname
+  | Lean -> fname
+
+(** Provided a basename, compute the name of a global declaration. *)
+let ctx_compute_global_name (ctx : extraction_ctx) (name : llbc_name) : string =
+  (* Converting to snake case also lowercases the letters (in Rust, global
+   * names are written in capital letters). *)
+  let parts = List.map to_snake_case (ctx_compute_simple_name ctx name) in
+  String.concat "_" parts
+
+(** Helper function: generate a suffix for a function name, i.e., generates
+    a suffix like "_loop", "loop1", etc. to append to a function name.
+ *)
+let default_fun_loop_suffix (num_loops : int) (loop_id : LoopId.id option) :
+    string =
+  match loop_id with
+  | None -> ""
+  | Some loop_id ->
+      (* If this is for a loop, generally speaking, we append the loop index.
+         If this function admits only one loop, we omit it. *)
+      if num_loops = 1 then "_loop" else "_loop" ^ LoopId.to_string loop_id
+
+(** A helper function: generates a function suffix from a region group
+    information.
+    TODO: move all those helpers.
+*)
+let default_fun_suffix (num_loops : int) (loop_id : LoopId.id option)
+    (num_region_groups : int) (rg : region_group_info option)
+    ((keep_fwd, num_backs) : bool * int) : string =
+  let lp_suff = default_fun_loop_suffix num_loops loop_id in
+
+  (* There are several cases:
+     - [rg] is [Some]: this is a forward function:
+       - we add "_fwd"
+     - [rg] is [None]: this is a backward function:
+       - this function has one extracted backward function:
+         - if the forward function has been filtered, we add "_fwd_back":
+           the forward function is useless, so the unique backward function
+           takes its place, in a way
+         - otherwise we add "_back"
+       - this function has several backward functions: we add "_back" and an
+         additional suffix to identify the precise backward function
+     Note that we always add a suffix (in case there are no region groups,
+     we could not add the "_fwd" suffix) to prevent name clashes between
+     definitions (in particular between type and function definitions).
+  *)
+  let rg_suff =
+    (* TODO: make all the backends match what is done for Lean *)
+    match rg with
+    | None ->
+        if
+          (* In order to avoid name conflicts:
+           * - if the forward is eliminated, we add the suffix "_fwd" (it won't be used)
+           * - otherwise, no suffix (because the backward functions will have a suffix)
+           *)
+          num_backs = 1 && not keep_fwd
+        then "_fwd"
+        else ""
+    | Some rg ->
+        assert (num_region_groups > 0 && num_backs > 0);
+        if num_backs = 1 then
+          (* Exactly one backward function *)
+          if not keep_fwd then "" else "_back"
+        else if
+          (* Several region groups/backward functions:
+             - if all the regions in the group have names, we use those names
+             - otherwise we use an index
+          *)
+          List.for_all Option.is_some rg.region_names
+        then
+          (* Concatenate the region names *)
+          "_back" ^ String.concat "" (List.map Option.get rg.region_names)
+        else (* Use the region index *)
+          "_back" ^ RegionGroupId.to_string rg.id
+  in
+  lp_suff ^ rg_suff
+
+(** Compute the name of a regular (non-assumed) function.
+
+    Inputs:
+    - function basename (TODO: shouldn't appear for assumed functions?...)
+    - number of loops in the function (useful to check if we need to use
+      indices to derive unique names for the loops for instance - if there is
+      exactly one loop, we don't need to use indices)
+    - loop id (if pertinent)
+    - number of region groups
+    - region group information in case of a backward function
+      ([None] if forward function)
+    - pair:
+      - do we generate the forward function (it may have been filtered)?
+      - the number of *extracted backward functions* (same comment as for
+        the number of loops)
+        The number of extracted backward functions if not necessarily
+        equal to the number of region groups, because we may have
+        filtered some of them.
+    TODO: use the fun id for the assumed functions.
+ *)
+let ctx_compute_fun_name (ctx : extraction_ctx) (fname : llbc_name)
+    (num_loops : int) (loop_id : LoopId.id option) (num_rgs : int)
+    (rg : region_group_info option) (filter_info : bool * int) : string =
+  let fname = ctx_compute_fun_name_no_suffix ctx fname in
+  (* Compute the suffix *)
+  let suffix = default_fun_suffix num_loops loop_id num_rgs rg filter_info in
+  (* Concatenate *)
+  fname ^ suffix
+
+let ctx_compute_trait_decl_name (ctx : extraction_ctx) (trait_decl : trait_decl)
+    : string =
+  ctx_compute_type_name ctx trait_decl.llbc_name
+
+let ctx_compute_trait_impl_name (ctx : extraction_ctx) (trait_decl : trait_decl)
+    (trait_impl : trait_impl) : string =
+  (* We derive the trait impl name from the implemented trait.
+     For instance, if this implementation is an instance of `trait::Trait`
+     for `<foo::Foo, u32>`, we generate the name: "trait.TraitFooFooU32Inst".
+     Importantly, it is to be noted that the name is independent of the place
+     where the instance has been defined (it is indepedent of the file, etc.).
+  *)
+  let name =
+    let params = trait_impl.llbc_generics in
+    let args = trait_impl.llbc_impl_trait.decl_generics in
+    trait_name_with_generics_to_simple_name ctx.trans_ctx trait_decl.llbc_name
+      params args
+  in
+  let name = flatten_name name in
+  match !backend with
+  | FStar -> StringUtils.lowercase_first_letter name
+  | Coq | HOL4 | Lean -> name
+
+let ctx_compute_trait_decl_constructor (ctx : extraction_ctx)
+    (trait_decl : trait_decl) : string =
+  let name = ctx_compute_trait_decl_name ctx trait_decl in
+  ExtractBuiltin.mk_struct_constructor name
+
+(** Helper to derive names for parent trait clauses and for variables
+    for trait instances.
+
+    We derive the name from the type of the clause (i.e., the trait ref
+    the clause implements).
+    For instance, if a trait clause is for the trait ref "Trait<Box<usize>",
+    we generate a name like "traitBoxUsizeInst". This is more meaningful
+    that giving it a generic name with an index (such as "parent_clause_1"
+    or "inst3").
+
+    Because we want to be precise when deriving the name, we use the
+    original LLBC types, that is the types from before the translation
+    to pure, which simplifies types like boxes and references.
+ *)
+let ctx_compute_trait_clause_name (ctx : extraction_ctx)
+    (current_def_name : Types.name) (params : Types.generic_params)
+    (clauses : Types.trait_clause list) (clause_id : trait_clause_id) : string =
+  (* We derive the name of the clause from the trait instance.
+     For instance, if the clause gives us an instance of `Foo<u32>`,
+     we generate a name along the lines of "fooU32Inst".
+  *)
+  let clause =
+    (* If the current def and the trait decl referenced by the clause
+       are in the same namespace, we try to simplify the names. We do so by
+       removing the common prefixes in their names.
+
+       For instance, if we have:
+       {[
+         // This is file traits.rs
+         trait Parent {}
+
+         trait Child : Parent {}
+       ]}
+       For the parent clause of trait [Child] we would like to generate
+       the name: "ParentInst", rather than "traitParentInst".
+    *)
+    let prefix = Some current_def_name in
+    let clause =
+      List.find
+        (fun (c : Types.trait_clause) -> c.clause_id = clause_id)
+        clauses
+    in
+    let trait_id = clause.trait_id in
+    let impl_trait_decl = TraitDeclId.Map.find trait_id ctx.crate.trait_decls in
+    let args = clause.clause_generics in
+    trait_name_with_generics_to_simple_name ctx.trans_ctx ~prefix
+      impl_trait_decl.name params args
+  in
+  String.concat "" clause
+
+let ctx_compute_trait_parent_clause_name (ctx : extraction_ctx)
+    (trait_decl : trait_decl) (clause : trait_clause) : string =
+  (* We derive the name of the clause from the trait instance.
+     For instance, if the clause gives us an instance of `Foo<u32>`,
+     we generate a name along the lines of "fooU32Inst".
+  *)
+  (* We need to lookup the LLBC definitions, to have the original instantiation *)
+  let clause =
+    let current_def_name = trait_decl.llbc_name in
+    let params = trait_decl.llbc_generics in
+    ctx_compute_trait_clause_name ctx current_def_name params
+      trait_decl.llbc_parent_clauses clause.clause_id
+  in
+  let clause =
+    if !Config.record_fields_short_names then clause
+    else ctx_compute_trait_decl_name ctx trait_decl ^ "_" ^ clause
+  in
+  match !backend with
+  | FStar -> StringUtils.lowercase_first_letter clause
+  | Coq | HOL4 | Lean -> clause
+
+let ctx_compute_trait_type_name (ctx : extraction_ctx) (trait_decl : trait_decl)
+    (item : string) : string =
+  let name =
+    if !Config.record_fields_short_names then item
+    else ctx_compute_trait_decl_name ctx trait_decl ^ "_" ^ item
+  in
+  (* Constants are usually all capital letters.
+     Some backends do not support field names starting with a capital letter,
+     and it may be weird to lowercase everything (especially as it may lead
+     to more name collisions): we add a prefix when necessary.
+     For instance, it gives: "U" -> "tU"
+     Note that for some backends we prepend the type name (because those backends
+     can't disambiguate fields coming from different ADTs if they have the same
+     names), and thus don't need to add a prefix starting with a lowercase.
+  *)
+  match !backend with FStar -> "t" ^ name | Coq | Lean | HOL4 -> name
+
+let ctx_compute_trait_const_name (ctx : extraction_ctx)
+    (trait_decl : trait_decl) (item : string) : string =
+  let name =
+    if !Config.record_fields_short_names then item
+    else ctx_compute_trait_decl_name ctx trait_decl ^ "_" ^ item
+  in
+  (* See [trait_type_name] *)
+  match !backend with FStar -> "c" ^ name | Coq | Lean | HOL4 -> name
+
+let ctx_compute_trait_method_name (ctx : extraction_ctx)
+    (trait_decl : trait_decl) (item : string) : string =
+  if !Config.record_fields_short_names then item
+  else ctx_compute_trait_decl_name ctx trait_decl ^ "_" ^ item
+
+let ctx_compute_trait_type_clause_name (ctx : extraction_ctx)
+    (trait_decl : trait_decl) (item : string) (clause : trait_clause) : string =
+  (* TODO: improve - it would be better to not use indices *)
+  ctx_compute_trait_type_name ctx trait_decl item
+  ^ "_clause_"
+  ^ TraitClauseId.to_string clause.clause_id
+
+(** Generates the name of the termination measure used to prove/reason about
+    termination. The generated code uses this clause where needed,
+    but its body must be defined by the user.
+
+    F* and Lean only.
+
+    Inputs:
+    - function id: this is especially useful to identify whether the
+      function is an assumed function or a local function
+    - function basename
+    - the number of loops in the parent function. This is used for
+      the same purpose as in {!field:llbc_name}.
+    - loop identifier, if this is for a loop
+ *)
+let ctx_compute_termination_measure_name (ctx : extraction_ctx)
+    (_fid : A.FunDeclId.id) (fname : llbc_name) (num_loops : int)
+    (loop_id : LoopId.id option) : string =
+  let fname = ctx_compute_fun_name_no_suffix ctx fname in
+  let lp_suffix = default_fun_loop_suffix num_loops loop_id in
+  (* Compute the suffix *)
+  let suffix =
+    match !Config.backend with
+    | FStar -> "_decreases"
+    | Lean -> "_terminates"
+    | Coq | HOL4 -> raise (Failure "Unexpected")
+  in
+  (* Concatenate *)
+  fname ^ lp_suffix ^ suffix
+
+(** Generates the name of the proof used to prove/reason about
+    termination. The generated code uses this clause where needed,
+    but its body must be defined by the user.
+
+    Lean only.
+
+    Inputs:
+    - function id: this is especially useful to identify whether the
+      function is an assumed function or a local function
+    - function basename
+    - the number of loops in the parent function. This is used for
+      the same purpose as in {!field:llbc_name}.
+    - loop identifier, if this is for a loop
+ *)
+let ctx_compute_decreases_proof_name (ctx : extraction_ctx)
+    (_fid : A.FunDeclId.id) (fname : llbc_name) (num_loops : int)
+    (loop_id : LoopId.id option) : string =
+  let fname = ctx_compute_fun_name_no_suffix ctx fname in
+  let lp_suffix = default_fun_loop_suffix num_loops loop_id in
+  (* Compute the suffix *)
+  let suffix =
+    match !Config.backend with
+    | Lean -> "_decreases"
+    | FStar | Coq | HOL4 -> raise (Failure "Unexpected")
+  in
+  (* Concatenate *)
+  fname ^ lp_suffix ^ suffix
+
+(** Generates a variable basename.
+
+    Inputs:
+    - the set of names used in the context so far
+    - the basename we got from the symbolic execution, if we have one
+    - the type of the variable (can be useful for heuristics, in order
+      not to always use "x" for instance, whenever naming anonymous
+      variables)
+
+    Note that once the formatter generated a basename, we add an index
+    if necessary to prevent name clashes: the burden of name clashes checks
+    is thus on the caller's side.
+ *)
+let ctx_compute_var_basename (ctx : extraction_ctx) (basename : string option)
+    (ty : ty) : string =
+  (* Small helper to derive var names from ADT type names.
+
+     We do the following:
+     - convert the type name to snake case
+     - take the first letter of every "letter group"
+     Ex.: "HashMap" -> "hash_map" -> "hm"
+  *)
+  let name_from_type_ident (name : string) : string =
+    let cl = to_snake_case name in
+    let cl = String.split_on_char '_' cl in
+    let cl = List.filter (fun s -> String.length s > 0) cl in
+    assert (List.length cl > 0);
+    let cl = List.map (fun s -> s.[0]) cl in
+    StringUtils.string_of_chars cl
+  in
+  (* If there is a basename, we use it *)
+  match basename with
+  | Some basename ->
+      (* This should be a no-op *)
+      to_snake_case basename
+  | None -> (
+      (* No basename: we use the first letter of the type *)
+      match ty with
+      | TAdt (type_id, generics) -> (
+          match type_id with
+          | TTuple ->
+              (* The "pair" case is frequent enough to have its special treatment *)
+              if List.length generics.types = 2 then "p" else "t"
+          | TAssumed TResult -> "r"
+          | TAssumed TError -> ConstStrings.error_basename
+          | TAssumed TFuel -> ConstStrings.fuel_basename
+          | TAssumed TArray -> "a"
+          | TAssumed TSlice -> "s"
+          | TAssumed TStr -> "s"
+          | TAssumed TState -> ConstStrings.state_basename
+          | TAssumed (TRawPtr _) -> "p"
+          | TAdtId adt_id ->
+              let def =
+                TypeDeclId.Map.find adt_id ctx.trans_ctx.type_ctx.type_decls
+              in
+              (* Derive the var name from the last ident of the type name
+                 Ex.: ["hashmap"; "HashMap"] ~~> "HashMap" -> "hash_map" -> "hm"
+              *)
+              (* The name shouldn't be empty, and its last element should
+               * be an ident *)
+              let cl = Collections.List.last def.name in
+              name_from_type_ident (TypesUtils.as_ident cl))
+      | TVar _ -> (
+          (* TODO: use "t" also for F* *)
+          match !backend with
+          | FStar -> "x" (* lacking inspiration here... *)
+          | Coq | Lean | HOL4 -> "t" (* lacking inspiration here... *))
+      | TLiteral lty -> (
+          match lty with TBool -> "b" | TChar -> "c" | TInteger _ -> "i")
+      | TArrow _ -> "f"
+      | TTraitType (_, _, name) -> name_from_type_ident name)
+
+(** Generates a type variable basename. *)
+let ctx_compute_type_var_basename (_ctx : extraction_ctx) (basename : string) :
+    string =
+  (* Rust type variables are snake-case and start with a capital letter *)
+  match !backend with
+  | FStar ->
+      (* This is *not* a no-op: this removes the capital letter *)
+      to_snake_case basename
+  | HOL4 ->
+      (* In HOL4, type variable names must start with "'" *)
+      "'" ^ to_snake_case basename
+  | Coq | Lean -> basename
+
+(** Generates a const generic variable basename. *)
+let ctx_compute_const_generic_var_basename (_ctx : extraction_ctx)
+    (basename : string) : string =
+  (* Rust type variables are snake-case and start with a capital letter *)
+  match !backend with
+  | FStar | HOL4 ->
+      (* This is *not* a no-op: this removes the capital letter *)
+      to_snake_case basename
+  | Coq | Lean -> basename
+
+(** Return a base name for a trait clause. We might add a suffix to prevent
+    collisions.
+
+    In the traduction we explicitely manipulate the trait clause instances,
+    that is we introduce one input variable for each trait clause.
+ *)
+let ctx_compute_trait_clause_basename (ctx : extraction_ctx)
+    (current_def_name : Types.name) (params : Types.generic_params)
+    (clause_id : trait_clause_id) : string =
+  (* This is similar to {!ctx_compute_trait_parent_clause_name}: we
+     derive the name from the trait reference (i.e., from the type) *)
+  let clause =
+    ctx_compute_trait_clause_name ctx current_def_name params
+      params.trait_clauses clause_id
+  in
+  match !backend with
+  | FStar | Coq | HOL4 -> StringUtils.lowercase_first_letter clause
+  | Lean -> clause
+
+let trait_self_clause_basename = "self_clause"
+
+(** Appends an index to a name - we use this to generate unique
+    names: when doing so, the role of the formatter is just to concatenate
+    indices to names, the responsability of finding a proper index is
+    delegated to helper functions.
+ *)
+let name_append_index (basename : string) (i : int) : string =
+  basename ^ string_of_int i
 
 (** Generate a unique type variable name and add it to the context *)
 let ctx_add_type_var (basename : string) (id : TypeVarId.id)
     (ctx : extraction_ctx) : extraction_ctx * string =
+  let name = ctx_compute_type_var_basename ctx basename in
   let name =
-    ctx.fmt.type_var_basename ctx.names_maps.names_map.names_set basename
-  in
-  let name =
-    basename_to_unique ctx.names_maps.names_map.names_set ctx.fmt.append_index
-      name
+    basename_to_unique ctx.names_maps.names_map.names_set name_append_index name
   in
   let ctx = ctx_add (TypeVarId id) name ctx in
   (ctx, name)
@@ -1049,13 +1806,9 @@ let ctx_add_type_var (basename : string) (id : TypeVarId.id)
 (** Generate a unique const generic variable name and add it to the context *)
 let ctx_add_const_generic_var (basename : string) (id : ConstGenericVarId.id)
     (ctx : extraction_ctx) : extraction_ctx * string =
+  let name = ctx_compute_const_generic_var_basename ctx basename in
   let name =
-    ctx.fmt.const_generic_var_basename ctx.names_maps.names_map.names_set
-      basename
-  in
-  let name =
-    basename_to_unique ctx.names_maps.names_map.names_set ctx.fmt.append_index
-      name
+    basename_to_unique ctx.names_maps.names_map.names_set name_append_index name
   in
   let ctx = ctx_add (ConstGenericVarId id) name ctx in
   (ctx, name)
@@ -1071,7 +1824,7 @@ let ctx_add_type_vars (vars : (string * TypeVarId.id) list)
 let ctx_add_var (basename : string) (id : VarId.id) (ctx : extraction_ctx) :
     extraction_ctx * string =
   let name =
-    basename_to_unique ctx.names_maps.names_map.names_set ctx.fmt.append_index
+    basename_to_unique ctx.names_maps.names_map.names_set name_append_index
       basename
   in
   let ctx = ctx_add (VarId id) name ctx in
@@ -1079,9 +1832,9 @@ let ctx_add_var (basename : string) (id : VarId.id) (ctx : extraction_ctx) :
 
 (** Generate a unique variable name for the trait self clause and add it to the context *)
 let ctx_add_trait_self_clause (ctx : extraction_ctx) : extraction_ctx * string =
-  let basename = ctx.fmt.trait_self_clause_basename in
+  let basename = trait_self_clause_basename in
   let name =
-    basename_to_unique ctx.names_maps.names_map.names_set ctx.fmt.append_index
+    basename_to_unique ctx.names_maps.names_map.names_set name_append_index
       basename
   in
   let ctx = ctx_add TraitSelfClauseId name ctx in
@@ -1091,7 +1844,7 @@ let ctx_add_trait_self_clause (ctx : extraction_ctx) : extraction_ctx * string =
 let ctx_add_local_trait_clause (basename : string) (id : TraitClauseId.id)
     (ctx : extraction_ctx) : extraction_ctx * string =
   let name =
-    basename_to_unique ctx.names_maps.names_map.names_set ctx.fmt.append_index
+    basename_to_unique ctx.names_maps.names_map.names_set name_append_index
       basename
   in
   let ctx = ctx_add (LocalTraitClauseId id) name ctx in
@@ -1102,9 +1855,7 @@ let ctx_add_vars (vars : var list) (ctx : extraction_ctx) :
     extraction_ctx * string list =
   List.fold_left_map
     (fun ctx (v : var) ->
-      let name =
-        ctx.fmt.var_basename ctx.names_maps.names_map.names_set v.basename v.ty
-      in
+      let name = ctx_compute_var_basename ctx v.basename v.ty in
       ctx_add_var name v.id ctx)
     ctx vars
 
@@ -1121,12 +1872,23 @@ let ctx_add_const_generic_params (vars : const_generic_var list)
       ctx_add_const_generic_var var.name var.index ctx)
     ctx vars
 
-let ctx_add_local_trait_clauses (clauses : trait_clause list)
+(** Returns the lists of names for:
+    - the type variables
+    - the const generic variables
+    - the trait clauses
+
+    For the [current_name_def] and the [llbc_generics]: we use them to derive
+    pretty names for the trait clauses. See {!ctx_compute_trait_clause_name}
+    for additional information.
+  *)
+let ctx_add_local_trait_clauses (current_def_name : Types.name)
+    (llbc_generics : Types.generic_params) (clauses : trait_clause list)
     (ctx : extraction_ctx) : extraction_ctx * string list =
   List.fold_left_map
     (fun ctx (c : trait_clause) ->
       let basename =
-        ctx.fmt.trait_clause_basename ctx.names_maps.names_map.names_set c
+        ctx_compute_trait_clause_basename ctx current_def_name llbc_generics
+          c.clause_id
       in
       ctx_add_local_trait_clause basename c.clause_id ctx)
     ctx clauses
@@ -1135,30 +1897,38 @@ let ctx_add_local_trait_clauses (clauses : trait_clause list)
     - the type variables
     - the const generic variables
     - the trait clauses
+
+    For the [current_name_def] and the [llbc_generics]: we use them to derive
+    pretty names for the trait clauses. See {!ctx_compute_trait_clause_name}
+    for additional information.
   *)
-let ctx_add_generic_params (generics : generic_params) (ctx : extraction_ctx) :
+let ctx_add_generic_params (current_def_name : Types.name)
+    (llbc_generics : Types.generic_params) (generics : generic_params)
+    (ctx : extraction_ctx) :
     extraction_ctx * string list * string list * string list =
   let { types; const_generics; trait_clauses } = generics in
   let ctx, tys = ctx_add_type_params types ctx in
   let ctx, cgs = ctx_add_const_generic_params const_generics ctx in
-  let ctx, tcs = ctx_add_local_trait_clauses trait_clauses ctx in
+  let ctx, tcs =
+    ctx_add_local_trait_clauses current_def_name llbc_generics trait_clauses ctx
+  in
   (ctx, tys, cgs, tcs)
 
 let ctx_add_decreases_proof (def : fun_decl) (ctx : extraction_ctx) :
     extraction_ctx =
   let name =
-    ctx.fmt.decreases_proof_name def.def_id def.basename def.num_loops
+    ctx_compute_decreases_proof_name ctx def.def_id def.llbc_name def.num_loops
       def.loop_id
   in
-  ctx_add (DecreasesProofId (Regular def.def_id, def.loop_id)) name ctx
+  ctx_add (DecreasesProofId (FRegular def.def_id, def.loop_id)) name ctx
 
 let ctx_add_termination_measure (def : fun_decl) (ctx : extraction_ctx) :
     extraction_ctx =
   let name =
-    ctx.fmt.termination_measure_name def.def_id def.basename def.num_loops
-      def.loop_id
+    ctx_compute_termination_measure_name ctx def.def_id def.llbc_name
+      def.num_loops def.loop_id
   in
-  ctx_add (TerminationMeasureId (Regular def.def_id, def.loop_id)) name ctx
+  ctx_add (TerminationMeasureId (FRegular def.def_id, def.loop_id)) name ctx
 
 let ctx_add_global_decl_and_body (def : A.global_decl) (ctx : extraction_ctx) :
     extraction_ctx =
@@ -1168,15 +1938,14 @@ let ctx_add_global_decl_and_body (def : A.global_decl) (ctx : extraction_ctx) :
   (* Check if the global corresponds to an assumed global that we should map
      to a custom definition in our standard library (for instance, happens
      with "core::num::usize::MAX") *)
-  let sname = name_to_simple_name def.name in
-  match SimpleNameMap.find_opt sname builtin_globals_map with
+  match match_name_find_opt ctx.trans_ctx def.name builtin_globals_map with
   | Some name ->
       (* Yes: register the custom binding *)
       ctx_add decl name ctx
   | None ->
       (* Not the case: "standard" registration *)
-      let name = ctx.fmt.global_name def.name in
-      let body = FunId (FromLlbc (FunId (Regular def.body_id), None, None)) in
+      let name = ctx_compute_global_name ctx def.name in
+      let body = FunId (FromLlbc (FunId (FRegular def.body), None, None)) in
       let ctx = ctx_add decl (name ^ "_c") ctx in
       let ctx = ctx_add body (name ^ "_body") ctx in
       ctx
@@ -1187,24 +1956,28 @@ let ctx_compute_fun_name (trans_group : pure_fun_translation) (def : fun_decl)
   let def_id = def.def_id in
   let llbc_def = A.FunDeclId.Map.find def_id ctx.trans_ctx.fun_ctx.fun_decls in
   let sg = llbc_def.signature in
-  let num_rgs = List.length sg.regions_hierarchy in
+  let regions_hierarchy =
+    LlbcAstUtils.FunIdMap.find (FRegular def_id)
+      ctx.trans_ctx.fun_ctx.regions_hierarchies
+  in
+  let num_rgs = List.length regions_hierarchy in
   let { keep_fwd; fwd = _; backs } = trans_group in
   let num_backs = List.length backs in
   let rg_info =
     match def.back_id with
     | None -> None
     | Some rg_id ->
-        let rg = T.RegionGroupId.nth sg.regions_hierarchy rg_id in
+        let rg = T.RegionGroupId.nth regions_hierarchy rg_id in
         let region_names =
           List.map
-            (fun rid -> (T.RegionVarId.nth sg.generics.regions rid).name)
+            (fun rid -> (T.RegionId.nth sg.generics.regions rid).name)
             rg.regions
         in
         Some { id = rg_id; region_names }
   in
   (* Add the function name *)
-  ctx.fmt.fun_name def.basename def.num_loops def.loop_id num_rgs rg_info
-    (keep_fwd, num_backs)
+  ctx_compute_fun_name ctx def.llbc_name def.num_loops def.loop_id num_rgs
+    rg_info (keep_fwd, num_backs)
 
 (* TODO: move to Extract *)
 let ctx_add_fun_decl (trans_group : pure_fun_translation) (def : fun_decl)
@@ -1218,7 +1991,7 @@ let ctx_add_fun_decl (trans_group : pure_fun_translation) (def : fun_decl)
   let num_backs = List.length backs in
   (* Add the function name *)
   let def_name = ctx_compute_fun_name trans_group def ctx in
-  let fun_id = (Pure.FunId (Regular def_id), def.loop_id, def.back_id) in
+  let fun_id = (Pure.FunId (FRegular def_id), def.loop_id, def.back_id) in
   let ctx = ctx_add (FunId (FromLlbc fun_id)) def_name ctx in
   (* Add the name info *)
   {
@@ -1228,156 +2001,6 @@ let ctx_add_fun_decl (trans_group : pure_fun_translation) (def : fun_decl)
         ctx.fun_name_info;
   }
 
-type names_map_init = {
-  keywords : string list;
-  assumed_adts : (assumed_ty * string) list;
-  assumed_structs : (assumed_ty * string) list;
-  assumed_variants : (assumed_ty * VariantId.id * string) list;
-  assumed_llbc_functions :
-    (A.assumed_fun_id * RegionGroupId.id option * string) list;
-  assumed_pure_functions : (pure_assumed_fun_id * string) list;
-}
-
-(** Initialize names maps with a proper set of keywords/names coming from the
-    target language/prover. *)
-let initialize_names_maps (fmt : formatter) (init : names_map_init) : names_maps
+let ctx_compute_type_decl_name (ctx : extraction_ctx) (def : type_decl) : string
     =
-  let int_names = List.map fmt.int_name T.all_int_types in
-  let keywords =
-    List.concat
-      [
-        [ fmt.bool_name; fmt.char_name; fmt.str_name ]; int_names; init.keywords;
-      ]
-  in
-  let names_set = StringSet.empty in
-  let name_to_id = StringMap.empty in
-  (* We fist initialize [id_to_name] as empty, because the id of a keyword is [UnknownId].
-   * Also note that we don't need this mapping for keywords: we insert keywords only
-   * to check collisions. *)
-  let id_to_name = IdMap.empty in
-  let names_map = { id_to_name; name_to_id; names_set } in
-  let unsafe_names_map = empty_unsafe_names_map in
-  let strict_names_map = empty_names_map in
-  (* For debugging - we are creating bindings for assumed types and functions, so
-   * it is ok if we simply use the "show" function (those aren't simply identified
-   * by numbers) *)
-  let id_to_string = show_id in
-  (* Add the keywords as strict collisions *)
-  let strict_names_map =
-    List.fold_left
-      (fun nm name ->
-        (* There is duplication in the keywords so we don't check the collisions
-           while registering them (what is important is that there are no collisions
-           between keywords and user-defined identifiers) *)
-        names_map_add_unchecked UnknownId name nm)
-      strict_names_map keywords
-  in
-  let nm = { names_map; unsafe_names_map; strict_names_map } in
-  (* Then we add:
-   * - the assumed types
-   * - the assumed struct constructors
-   * - the assumed variants
-   * - the assumed functions
-   *)
-  let nm =
-    List.fold_left
-      (fun nm (type_id, name) ->
-        names_maps_add_assumed_type id_to_string type_id name nm)
-      nm init.assumed_adts
-  in
-  let nm =
-    List.fold_left
-      (fun nm (type_id, name) ->
-        names_maps_add_assumed_struct id_to_string type_id name nm)
-      nm init.assumed_structs
-  in
-  let nm =
-    List.fold_left
-      (fun nm (type_id, variant_id, name) ->
-        names_maps_add_assumed_variant id_to_string type_id variant_id name nm)
-      nm init.assumed_variants
-  in
-  let assumed_functions =
-    List.map
-      (fun (fid, rg, name) ->
-        (FromLlbc (Pure.FunId (Assumed fid), None, rg), name))
-      init.assumed_llbc_functions
-    @ List.map (fun (fid, name) -> (Pure fid, name)) init.assumed_pure_functions
-  in
-  let nm =
-    List.fold_left
-      (fun nm (fid, name) -> names_maps_add_function id_to_string fid name nm)
-      nm assumed_functions
-  in
-  (* Return *)
-  nm
-
-let compute_type_decl_name (fmt : formatter) (def : type_decl) : string =
-  fmt.type_name def.name
-
-(** Helper function: generate a suffix for a function name, i.e., generates
-    a suffix like "_loop", "loop1", etc. to append to a function name.
- *)
-let default_fun_loop_suffix (num_loops : int) (loop_id : LoopId.id option) :
-    string =
-  match loop_id with
-  | None -> ""
-  | Some loop_id ->
-      (* If this is for a loop, generally speaking, we append the loop index.
-         If this function admits only one loop, we omit it. *)
-      if num_loops = 1 then "_loop" else "_loop" ^ LoopId.to_string loop_id
-
-(** A helper function: generates a function suffix from a region group
-    information.
-    TODO: move all those helpers.
-*)
-let default_fun_suffix (num_loops : int) (loop_id : LoopId.id option)
-    (num_region_groups : int) (rg : region_group_info option)
-    ((keep_fwd, num_backs) : bool * int) : string =
-  let lp_suff = default_fun_loop_suffix num_loops loop_id in
-
-  (* There are several cases:
-     - [rg] is [Some]: this is a forward function:
-       - we add "_fwd"
-     - [rg] is [None]: this is a backward function:
-       - this function has one extracted backward function:
-         - if the forward function has been filtered, we add "_fwd_back":
-           the forward function is useless, so the unique backward function
-           takes its place, in a way
-         - otherwise we add "_back"
-       - this function has several backward functions: we add "_back" and an
-         additional suffix to identify the precise backward function
-     Note that we always add a suffix (in case there are no region groups,
-     we could not add the "_fwd" suffix) to prevent name clashes between
-     definitions (in particular between type and function definitions).
-  *)
-  let rg_suff =
-    (* TODO: make all the backends match what is done for Lean *)
-    match rg with
-    | None ->
-        if
-          (* In order to avoid name conflicts:
-           * - if the forward is eliminated, we add the suffix "_fwd" (it won't be used)
-           * - otherwise, no suffix (because the backward functions will have a suffix)
-           *)
-          num_backs = 1 && not keep_fwd
-        then "_fwd"
-        else ""
-    | Some rg ->
-        assert (num_region_groups > 0 && num_backs > 0);
-        if num_backs = 1 then
-          (* Exactly one backward function *)
-          if not keep_fwd then "" else "_back"
-        else if
-          (* Several region groups/backward functions:
-             - if all the regions in the group have names, we use those names
-             - otherwise we use an index
-          *)
-          List.for_all Option.is_some rg.region_names
-        then
-          (* Concatenate the region names *)
-          "_back" ^ String.concat "" (List.map Option.get rg.region_names)
-        else (* Use the region index *)
-          "_back" ^ RegionGroupId.to_string rg.id
-  in
-  lp_suff ^ rg_suff
+  ctx_compute_type_name ctx def.llbc_name
diff --git a/compiler/ExtractBuiltin.ml b/compiler/ExtractBuiltin.ml
index a54ab604..30ec7c19 100644
--- a/compiler/ExtractBuiltin.ml
+++ b/compiler/ExtractBuiltin.ml
@@ -4,32 +4,11 @@
     TODO: there misses trait **implementations**
  *)
 
-open Names
 open Config
+open Charon.NameMatcher (* TODO: include? *)
+include ExtractName (* TODO: only open? *)
 
-type simple_name = string list [@@deriving show, ord]
-
-let name_to_simple_name (s : name) : simple_name =
-  (* We simply ignore the disambiguators *)
-  List.filter_map (function Ident id -> Some id | Disambiguator _ -> None) s
-
-(** Small helper which cuts a string at the occurrences of "::" *)
-let string_to_simple_name (s : string) : simple_name =
-  (* No function to split by using string separator?? *)
-  let name = String.split_on_char ':' s in
-  List.filter (fun s -> s <> "") name
-
-module SimpleNameOrd = struct
-  type t = simple_name
-
-  let compare = compare_simple_name
-  let to_string = show_simple_name
-  let pp_t = pp_simple_name
-  let show_t = show_simple_name
-end
-
-module SimpleNameMap = Collections.MakeMap (SimpleNameOrd)
-module SimpleNameSet = Collections.MakeSet (SimpleNameOrd)
+let log = Logging.builtin_log
 
 (** Small utility to memoize some computations *)
 let mk_memoized (f : unit -> 'a) : unit -> 'a =
@@ -44,6 +23,18 @@ let mk_memoized (f : unit -> 'a) : unit -> 'a =
   in
   g
 
+let split_on_separator (s : string) : string list =
+  Str.split (Str.regexp "\\(::\\|\\.\\)") s
+
+let flatten_name (name : string list) : string =
+  match !backend with
+  | FStar | Coq | HOL4 -> String.concat "_" name
+  | Lean -> String.concat "." name
+
+let () =
+  assert (split_on_separator "x::y::z" = [ "x"; "y"; "z" ]);
+  assert (split_on_separator "x.y.z" = [ "x"; "y"; "z" ])
+
 (** Switch between two values depending on the target backend.
 
     We often compute the same value (typically: a name) if the target
@@ -55,36 +46,36 @@ let backend_choice (fstar_coq_hol4 : 'a) (lean : 'a) : 'a =
 let builtin_globals : (string * string) list =
   [
     (* Min *)
-    ("core::num::usize::MIN", "core_usize_min");
-    ("core::num::u8::MIN", "core_u8_min");
-    ("core::num::u16::MIN", "core_u16_min");
-    ("core::num::u32::MIN", "core_u32_min");
-    ("core::num::u64::MIN", "core_u64_min");
-    ("core::num::u128::MIN", "core_u128_min");
-    ("core::num::isize::MIN", "core_isize_min");
-    ("core::num::i8::MIN", "core_i8_min");
-    ("core::num::i16::MIN", "core_i16_min");
-    ("core::num::i32::MIN", "core_i32_min");
-    ("core::num::i64::MIN", "core_i64_min");
-    ("core::num::i128::MIN", "core_i128_min");
+    ("core::num::{usize}::MIN", "core_usize_min");
+    ("core::num::{u8}::MIN", "core_u8_min");
+    ("core::num::{u16}::MIN", "core_u16_min");
+    ("core::num::{u32}::MIN", "core_u32_min");
+    ("core::num::{u64}::MIN", "core_u64_min");
+    ("core::num::{u128}::MIN", "core_u128_min");
+    ("core::num::{isize}::MIN", "core_isize_min");
+    ("core::num::{i8}::MIN", "core_i8_min");
+    ("core::num::{i16}::MIN", "core_i16_min");
+    ("core::num::{i32}::MIN", "core_i32_min");
+    ("core::num::{i64}::MIN", "core_i64_min");
+    ("core::num::{i128}::MIN", "core_i128_min");
     (* Max *)
-    ("core::num::usize::MAX", "core_usize_max");
-    ("core::num::u8::MAX", "core_u8_max");
-    ("core::num::u16::MAX", "core_u16_max");
-    ("core::num::u32::MAX", "core_u32_max");
-    ("core::num::u64::MAX", "core_u64_max");
-    ("core::num::u128::MAX", "core_u128_max");
-    ("core::num::isize::MAX", "core_isize_max");
-    ("core::num::i8::MAX", "core_i8_max");
-    ("core::num::i16::MAX", "core_i16_max");
-    ("core::num::i32::MAX", "core_i32_max");
-    ("core::num::i64::MAX", "core_i64_max");
-    ("core::num::i128::MAX", "core_i128_max");
+    ("core::num::{usize}::MAX", "core_usize_max");
+    ("core::num::{u8}::MAX", "core_u8_max");
+    ("core::num::{u16}::MAX", "core_u16_max");
+    ("core::num::{u32}::MAX", "core_u32_max");
+    ("core::num::{u64}::MAX", "core_u64_max");
+    ("core::num::{u128}::MAX", "core_u128_max");
+    ("core::num::{isize}::MAX", "core_isize_max");
+    ("core::num::{i8}::MAX", "core_i8_max");
+    ("core::num::{i16}::MAX", "core_i16_max");
+    ("core::num::{i32}::MAX", "core_i32_max");
+    ("core::num::{i64}::MAX", "core_i64_max");
+    ("core::num::{i128}::MAX", "core_i128_max");
   ]
 
-let builtin_globals_map : string SimpleNameMap.t =
-  SimpleNameMap.of_list
-    (List.map (fun (x, y) -> (string_to_simple_name x, y)) builtin_globals)
+let builtin_globals_map : string NameMatcherMap.t =
+  NameMatcherMap.of_list
+    (List.map (fun (x, y) -> (parse_pattern x, y)) builtin_globals)
 
 type builtin_variant_info = { fields : (string * string) list }
 [@@deriving show]
@@ -104,7 +95,7 @@ type builtin_type_body_info =
 [@@deriving show]
 
 type builtin_type_info = {
-  rust_name : string list;
+  rust_name : pattern;
   extract_name : string;
   keep_params : bool list option;
       (** We might want to filter some of the type parameters.
@@ -136,12 +127,9 @@ let mk_struct_constructor (type_name : string) : string =
     a type parameter for the allocator to use, which we want to filter.
  *)
 let builtin_types () : builtin_type_info list =
-  let mk_type (rust_name : string list) ?(keep_params : bool list option = None)
+  let mk_type (rust_name : string) ?(keep_params : bool list option = None)
       ?(kind : type_variant_kind = KOpaque) () : builtin_type_info =
-    let extract_name =
-      let sep = backend_choice "_" "." in
-      String.concat sep rust_name
-    in
+    let extract_name = flatten_name (split_on_separator rust_name) in
     let body_info : builtin_type_body_info option =
       match kind with
       | KOpaque -> None
@@ -159,17 +147,17 @@ let builtin_types () : builtin_type_info list =
           Some (Struct (constructor, fields))
       | KEnum -> raise (Failure "TODO")
     in
+    let rust_name = parse_pattern rust_name in
     { rust_name; extract_name; keep_params; body_info }
   in
 
   [
     (* Alloc *)
-    mk_type [ "alloc"; "alloc"; "Global" ] ();
+    mk_type "alloc::alloc::Global" ();
     (* Vec *)
-    mk_type [ "alloc"; "vec"; "Vec" ] ~keep_params:(Some [ true; false ]) ();
+    mk_type "alloc::vec::Vec" ~keep_params:(Some [ true; false ]) ();
     (* Range *)
-    mk_type
-      [ "core"; "ops"; "range"; "Range" ]
+    mk_type "core::ops::range::Range"
       ~kind:(KStruct [ ("start", "start"); ("end", "end_") ])
       ();
     (* Option
@@ -178,7 +166,7 @@ let builtin_types () : builtin_type_info list =
        the target backend.
     *)
     {
-      rust_name = [ "core"; "option"; "Option" ];
+      rust_name = parse_pattern "core::option::Option";
       extract_name =
         (match !backend with
         | Lean -> "Option"
@@ -211,7 +199,7 @@ let builtin_types () : builtin_type_info list =
   ]
 
 let mk_builtin_types_map () =
-  SimpleNameMap.of_list
+  NameMatcherMap.of_list
     (List.map (fun info -> (info.rust_name, info)) (builtin_types ()))
 
 let builtin_types_map = mk_memoized mk_builtin_types_map
@@ -228,21 +216,24 @@ type builtin_fun_info = {
     parameters. For instance, in the case of the `Vec` functions, there is
     a type parameter for the allocator to use, which we want to filter.
  *)
-let builtin_funs () :
-    (string list * bool list option * builtin_fun_info list) list =
+let builtin_funs () : (pattern * bool list option * builtin_fun_info list) list
+    =
   let rg0 = Some Types.RegionGroupId.zero in
   (* Small utility *)
-  let mk_fun (name : string list) (extract_name : string list option)
+  let mk_fun (rust_name : string) (extract_name : string option)
       (filter : bool list option) (with_back : bool) (back_no_suffix : bool) :
-      string list * bool list option * builtin_fun_info list =
-    let extract_name =
-      match extract_name with None -> name | Some name -> name
+      pattern * bool list option * builtin_fun_info list =
+    let rust_name =
+      try parse_pattern rust_name
+      with Failure _ ->
+        raise (Failure ("Could not parse pattern: " ^ rust_name))
     in
-    let basename =
-      match !backend with
-      | FStar | Coq | HOL4 -> String.concat "_" extract_name
-      | Lean -> String.concat "." extract_name
+    let extract_name =
+      match extract_name with
+      | None -> pattern_to_fun_extract_name rust_name
+      | Some name -> split_on_separator name
     in
+    let basename = flatten_name extract_name in
     let fwd_suffix = if with_back && back_no_suffix then "_fwd" else "" in
     let fwd = [ { rg = None; extract_name = basename ^ fwd_suffix } ] in
     let back_suffix = if with_back && back_no_suffix then "" else "_back" in
@@ -250,106 +241,73 @@ let builtin_funs () :
       if with_back then [ { rg = rg0; extract_name = basename ^ back_suffix } ]
       else []
     in
-    (name, filter, fwd @ back)
+    (rust_name, filter, fwd @ back)
   in
   [
-    mk_fun [ "core"; "mem"; "replace" ] None None true false;
-    mk_fun [ "alloc"; "vec"; "Vec"; "new" ] None None false false;
-    mk_fun
-      [ "alloc"; "vec"; "Vec"; "push" ]
-      None
+    mk_fun "core::mem::replace" None None true false;
+    mk_fun "core::slice::{[@T]}::len"
+      (Some (backend_choice "slice::len" "Slice::len"))
+      None true false;
+    mk_fun "alloc::vec::{alloc::vec::Vec<@T, alloc::alloc::Global>}::new"
+      (Some "alloc::vec::Vec::new") None false false;
+    mk_fun "alloc::vec::{alloc::vec::Vec<@T, @A>}::push" None
       (Some [ true; false ])
       true true;
-    mk_fun
-      [ "alloc"; "vec"; "Vec"; "insert" ]
-      None
+    mk_fun "alloc::vec::{alloc::vec::Vec<@T, @A>}::insert" None
       (Some [ true; false ])
       true true;
-    mk_fun
-      [ "alloc"; "vec"; "Vec"; "len" ]
-      None
+    mk_fun "alloc::vec::{alloc::vec::Vec<@T, @A>}::len" None
       (Some [ true; false ])
       true false;
-    mk_fun
-      [ "alloc"; "vec"; "Vec"; "index" ]
-      None
+    mk_fun "alloc::vec::{alloc::vec::Vec<@T, @A>}::index" None
       (Some [ true; true; false ])
       true false;
-    mk_fun
-      [ "alloc"; "vec"; "Vec"; "index_mut" ]
-      None
+    mk_fun "alloc::vec::{alloc::vec::Vec<@T, @A>}::index_mut" None
       (Some [ true; true; false ])
       true false;
-    mk_fun
-      [ "alloc"; "boxed"; "Box"; "deref" ]
-      None
+    mk_fun "alloc::boxed::{Box<@T>}::deref" None
       (Some [ true; false ])
       true false;
-    mk_fun
-      [ "alloc"; "boxed"; "Box"; "deref_mut" ]
-      None
+    mk_fun "alloc::boxed::{Box<@T>}::deref_mut" None
       (Some [ true; false ])
       true false;
-    (* TODO: fix the same like "[T]" below *)
-    mk_fun
-      [ "core"; "slice"; "index"; "[T]"; "index" ]
-      (Some [ "core"; "slice"; "index"; "Slice"; "index" ])
-      None true false;
-    mk_fun
-      [ "core"; "slice"; "index"; "[T]"; "index_mut" ]
-      (Some [ "core"; "slice"; "index"; "Slice"; "index_mut" ])
-      None true false;
-    mk_fun
-      [ "core"; "array"; "[T; N]"; "index" ]
-      (Some [ "core"; "array"; "Array"; "index" ])
-      None true false;
-    mk_fun
-      [ "core"; "array"; "[T; N]"; "index_mut" ]
-      (Some [ "core"; "array"; "Array"; "index_mut" ])
-      None true false;
-    mk_fun [ "core"; "slice"; "index"; "Range"; "get" ] None None true false;
-    mk_fun [ "core"; "slice"; "index"; "Range"; "get_mut" ] None None true false;
-    mk_fun [ "core"; "slice"; "index"; "Range"; "index" ] None None true false;
-    mk_fun
-      [ "core"; "slice"; "index"; "Range"; "index_mut" ]
-      None None true false;
-    mk_fun
-      [ "core"; "slice"; "index"; "Range"; "get_unchecked" ]
-      None None false false;
-    mk_fun
-      [ "core"; "slice"; "index"; "Range"; "get_unchecked_mut" ]
-      None None false false;
-    mk_fun
-      [ "core"; "slice"; "index"; "usize"; "get" ]
-      (Some [ "core"; "slice"; "index"; "Usize"; "get" ])
-      None true false;
+    mk_fun "core::slice::index::{[@T]}::index" None None true false;
+    mk_fun "core::slice::index::{[@T]}::index_mut" None None true false;
+    mk_fun "core::array::{[@T; @C]}::index" None None true false;
+    mk_fun "core::array::{[@T; @C]}::index_mut" None None true false;
+    mk_fun "core::slice::index::{core::ops::range::Range<usize>}::get"
+      (Some "core::slice::index::RangeUsize::get") None true false;
+    mk_fun "core::slice::index::{core::ops::range::Range<usize>}::get_mut"
+      (Some "core::slice::index::RangeUsize::get_mut") None true false;
+    mk_fun "core::slice::index::{core::ops::range::Range<usize>}::index"
+      (Some "core::slice::index::RangeUsize::index") None true false;
+    mk_fun "core::slice::index::{core::ops::range::Range<usize>}::index_mut"
+      (Some "core::slice::index::RangeUsize::index_mut") None true false;
+    mk_fun "core::slice::index::{core::ops::range::Range<usize>}::get_unchecked"
+      (Some "core::slice::index::RangeUsize::get_unchecked") None false false;
     mk_fun
-      [ "core"; "slice"; "index"; "usize"; "get_mut" ]
-      (Some [ "core"; "slice"; "index"; "Usize"; "get_mut" ])
-      None true false;
-    mk_fun
-      [ "core"; "slice"; "index"; "usize"; "get_unchecked" ]
-      (Some [ "core"; "slice"; "index"; "Usize"; "get_unchecked" ])
-      None false false;
-    mk_fun
-      [ "core"; "slice"; "index"; "usize"; "get_unchecked_mut" ]
-      (Some [ "core"; "slice"; "index"; "Usize"; "get_unchecked_mut" ])
-      None false false;
-    mk_fun
-      [ "core"; "slice"; "index"; "usize"; "index" ]
-      (Some [ "core"; "slice"; "index"; "Usize"; "index" ])
-      None true false;
-    mk_fun
-      [ "core"; "slice"; "index"; "usize"; "index_mut" ]
-      (Some [ "core"; "slice"; "index"; "Usize"; "index_mut" ])
-      None true false;
+      "core::slice::index::{core::ops::range::Range<usize>}::get_unchecked_mut"
+      (Some "core::slice::index::RangeUsize::get_unchecked_mut") None false
+      false;
+    mk_fun "core::slice::index::{usize}::get" None None true false;
+    mk_fun "core::slice::index::{usize}::get_mut" None None true false;
+    mk_fun "core::slice::index::{usize}::get_unchecked" None None false false;
+    mk_fun "core::slice::index::{usize}::get_unchecked_mut" None None false
+      false;
+    mk_fun "core::slice::index::{usize}::index" None None true false;
+    mk_fun "core::slice::index::{usize}::index_mut" None None true false;
   ]
 
 let mk_builtin_funs_map () =
-  SimpleNameMap.of_list
-    (List.map
-       (fun (name, filter, info) -> (name, (filter, info)))
-       (builtin_funs ()))
+  let m =
+    NameMatcherMap.of_list
+      (List.map
+         (fun (name, filter, info) -> (name, (filter, info)))
+         (builtin_funs ()))
+  in
+  log#ldebug
+    (lazy ("builtin_funs_map:\n" ^ NameMatcherMap.to_string (fun _ -> "...") m));
+  m
 
 let builtin_funs_map = mk_memoized mk_builtin_funs_map
 
@@ -378,17 +336,21 @@ let builtin_fun_effects =
   let int_funs =
     List.map
       (fun int_name ->
-        List.map (fun op -> "core::num::" ^ int_name ^ "::" ^ op) int_ops)
+        List.map
+          (fun op ->
+            "core::num::" ^ "{"
+            ^ StringUtils.capitalize_first_letter int_name
+            ^ "}::" ^ op)
+          int_ops)
       int_names
   in
   let int_funs = List.concat int_funs in
   let no_fail_no_state_funs =
     [
-      (* TODO: redundancy with the funs information below *)
-      "alloc::vec::Vec::new";
-      "alloc::vec::Vec::len";
-      "alloc::boxed::Box::deref";
-      "alloc::boxed::Box::deref_mut";
+      (* TODO: redundancy with the funs information above *)
+      "core::slice::{[@T]}::len";
+      "alloc::vec::{alloc::vec::Vec<@T, alloc::alloc::Global>}::new";
+      "alloc::vec::{alloc::vec::Vec<@T, @A>}::len";
       "core::mem::replace";
       "core::mem::take";
     ]
@@ -401,11 +363,11 @@ let builtin_fun_effects =
   in
   let no_state_funs =
     [
-      (* TODO: redundancy with the funs information below *)
-      "alloc::vec::Vec::push";
-      "alloc::vec::Vec::index";
-      "alloc::vec::Vec::index_mut";
-      "alloc::vec::Vec::index_mut_back";
+      (* TODO: redundancy with the funs information above *)
+      "alloc::vec::{alloc::vec::Vec<@T, @A>}::push";
+      "alloc::vec::{alloc::vec::Vec<@T, @A>}::index";
+      "alloc::vec::{alloc::vec::Vec<@T, @A>}::index_mut";
+      "alloc::vec::{alloc::vec::Vec<@T, @A>}::index_mut_back";
     ]
   in
   let no_state_funs =
@@ -414,11 +376,11 @@ let builtin_fun_effects =
   no_fail_no_state_funs @ no_state_funs
 
 let builtin_fun_effects_map =
-  SimpleNameMap.of_list
-    (List.map (fun (n, x) -> (string_to_simple_name n, x)) builtin_fun_effects)
+  NameMatcherMap.of_list
+    (List.map (fun (n, x) -> (parse_pattern n, x)) builtin_fun_effects)
 
 type builtin_trait_decl_info = {
-  rust_name : string;
+  rust_name : pattern;
   extract_name : string;
   constructor : string;
   parent_clauses : string list;
@@ -434,25 +396,29 @@ type builtin_trait_decl_info = {
 
 let builtin_trait_decls_info () =
   let rg0 = Some Types.RegionGroupId.zero in
-  let mk_trait (rust_name : string list) ?(extract_name : string option = None)
+  let mk_trait (rust_name : string) ?(extract_name : string option = None)
       ?(parent_clauses : string list = []) ?(types : string list = [])
       ?(methods : (string * bool) list = []) () : builtin_trait_decl_info =
+    let rust_name = parse_pattern rust_name in
     let extract_name =
       match extract_name with
       | Some n -> n
-      | None -> (
-          match !backend with
-          | Coq | FStar | HOL4 -> String.concat "_" rust_name
-          | Lean -> String.concat "." rust_name)
+      | None ->
+          let rust_name = pattern_to_fun_extract_name rust_name in
+          flatten_name rust_name
     in
     let constructor = mk_struct_constructor extract_name in
     let consts = [] in
     let types =
       let mk_type item_name =
         let type_name =
+          if !record_fields_short_names then item_name
+          else extract_name ^ "_" ^ item_name
+        in
+        let type_name =
           match !backend with
-          | Coq | FStar | HOL4 -> extract_name ^ "_" ^ item_name
-          | Lean -> item_name
+          | FStar | Coq | HOL4 -> StringUtils.lowercase_first_letter type_name
+          | Lean -> type_name
         in
         let clauses = [] in
         (item_name, (type_name, clauses))
@@ -463,9 +429,8 @@ let builtin_trait_decls_info () =
       let mk_method (item_name, with_back) =
         (* TODO: factor out with builtin_funs_info *)
         let basename =
-          match !backend with
-          | Coq | FStar | HOL4 -> extract_name ^ "_" ^ item_name
-          | Lean -> item_name
+          if !record_fields_short_names then item_name
+          else extract_name ^ "_" ^ item_name
         in
         let back_no_suffix = false in
         let fwd_suffix = if with_back && back_no_suffix then "_fwd" else "" in
@@ -480,7 +445,6 @@ let builtin_trait_decls_info () =
       in
       List.map mk_method methods
     in
-    let rust_name = String.concat "::" rust_name in
     {
       rust_name;
       extract_name;
@@ -493,35 +457,25 @@ let builtin_trait_decls_info () =
   in
   [
     (* Deref *)
-    mk_trait
-      [ "core"; "ops"; "deref"; "Deref" ]
-      ~types:[ "Target" ]
+    mk_trait "core::ops::deref::Deref" ~types:[ "Target" ]
       ~methods:[ ("deref", true) ]
       ();
     (* DerefMut *)
-    mk_trait
-      [ "core"; "ops"; "deref"; "DerefMut" ]
-      ~parent_clauses:[ backend_choice "deref_inst" "derefInst" ]
+    mk_trait "core::ops::deref::DerefMut" ~parent_clauses:[ "derefInst" ]
       ~methods:[ ("deref_mut", true) ]
       ();
     (* Index *)
-    mk_trait
-      [ "core"; "ops"; "index"; "Index" ]
-      ~types:[ "Output" ]
+    mk_trait "core::ops::index::Index" ~types:[ "Output" ]
       ~methods:[ ("index", true) ]
       ();
     (* IndexMut *)
-    mk_trait
-      [ "core"; "ops"; "index"; "IndexMut" ]
-      ~parent_clauses:[ backend_choice "index_inst" "indexInst" ]
+    mk_trait "core::ops::index::IndexMut" ~parent_clauses:[ "indexInst" ]
       ~methods:[ ("index_mut", true) ]
       ();
     (* Sealed *)
-    mk_trait [ "core"; "slice"; "index"; "private_slice_index"; "Sealed" ] ();
+    mk_trait "core::slice::index::private_slice_index::Sealed" ();
     (* SliceIndex *)
-    mk_trait
-      [ "core"; "slice"; "index"; "SliceIndex" ]
-      ~parent_clauses:[ backend_choice "sealed_inst" "sealedInst" ]
+    mk_trait "core::slice::index::SliceIndex" ~parent_clauses:[ "sealedInst" ]
       ~types:[ "Output" ]
       ~methods:
         [
@@ -536,113 +490,81 @@ let builtin_trait_decls_info () =
   ]
 
 let mk_builtin_trait_decls_map () =
-  SimpleNameMap.of_list
+  NameMatcherMap.of_list
     (List.map
-       (fun info -> (string_to_simple_name info.rust_name, info))
+       (fun info -> (info.rust_name, info))
        (builtin_trait_decls_info ()))
 
 let builtin_trait_decls_map = mk_memoized mk_builtin_trait_decls_map
 
-(* TODO: generalize this.
-
-   For now, the key is:
-   - name of the impl (ex.: "alloc.boxed.Boxed")
-   - name of the implemented trait (ex.: "core.ops.deref.Deref"
-*)
-type simple_name_pair = simple_name * simple_name [@@deriving show, ord]
-
-module SimpleNamePairOrd = struct
-  type t = simple_name_pair
-
-  let compare = compare_simple_name_pair
-  let to_string = show_simple_name_pair
-  let pp_t = pp_simple_name_pair
-  let show_t = show_simple_name_pair
-end
-
-module SimpleNamePairMap = Collections.MakeMap (SimpleNamePairOrd)
-
-let builtin_trait_impls_info () :
-    ((string list * string list) * (bool list option * string)) list =
-  let fmt (type_name : string list)
-      ?(extract_type_name : string list option = None)
-      (trait_name : string list) ?(filter : bool list option = None) () :
-      (string list * string list) * (bool list option * string) =
+let builtin_trait_impls_info () : (pattern * (bool list option * string)) list =
+  let fmt (rust_name : string) ?(extract_name : string option = None)
+      ?(filter : bool list option = None) () :
+      pattern * (bool list option * string) =
+    let rust_name = parse_pattern rust_name in
     let name =
-      let trait_name = String.concat "" trait_name ^ "Inst" in
-      let sep = backend_choice "_" "." in
-      let type_name =
-        match extract_type_name with
-        | Some type_name -> type_name
-        | None -> type_name
+      let name =
+        match extract_name with
+        | None -> pattern_to_trait_impl_extract_name rust_name
+        | Some name -> split_on_separator name
       in
-      String.concat sep type_name ^ sep ^ trait_name
+      flatten_name name
     in
-    ((type_name, trait_name), (filter, name))
+    (rust_name, (filter, name))
   in
-  (* TODO: fix the names like "[T]" below *)
   [
     (* core::ops::Deref<alloc::boxed::Box<T>> *)
-    fmt [ "alloc"; "boxed"; "Box" ] [ "core"; "ops"; "deref"; "Deref" ] ();
+    fmt "core::ops::deref::Deref<Box<@T>>"
+      ~extract_name:(Some "alloc::boxed::Box::coreopsDerefInst") ();
     (* core::ops::DerefMut<alloc::boxed::Box<T>> *)
-    fmt [ "alloc"; "boxed"; "Box" ] [ "core"; "ops"; "deref"; "DerefMut" ] ();
+    fmt "core::ops::deref::DerefMut<Box<@T>>"
+      ~extract_name:(Some "alloc::boxed::Box::coreopsDerefMutInst") ();
     (* core::ops::index::Index<[T], I> *)
-    fmt
-      [ "core"; "slice"; "index"; "[T]" ]
-      ~extract_type_name:(Some [ "core"; "slice"; "index"; "Slice" ])
-      [ "core"; "ops"; "index"; "Index" ]
-      ();
+    fmt "core::ops::index::Index<[@T], @I>"
+      ~extract_name:(Some "core::ops::index::IndexSliceTIInst") ();
     (* core::ops::index::IndexMut<[T], I> *)
-    fmt
-      [ "core"; "slice"; "index"; "[T]" ]
-      ~extract_type_name:(Some [ "core"; "slice"; "index"; "Slice" ])
-      [ "core"; "ops"; "index"; "IndexMut" ]
-      ();
+    fmt "core::ops::index::IndexMut<[@T], @I>"
+      ~extract_name:(Some "core::ops::index::IndexMutSliceTIInst") ();
     (* core::slice::index::private_slice_index::Sealed<Range<usize>> *)
     fmt
-      [ "core"; "slice"; "index"; "private_slice_index"; "Range" ]
-      [ "core"; "slice"; "index"; "private_slice_index"; "Sealed" ]
-      ();
+      "core::slice::index::private_slice_index::Sealed<core::ops::range::Range<usize>>"
+      ~extract_name:
+        (Some "core.slice.index.private_slice_index.SealedRangeUsizeInst") ();
     (* core::slice::index::SliceIndex<Range<usize>, [T]> *)
-    fmt
-      [ "core"; "slice"; "index"; "Range" ]
-      [ "core"; "slice"; "index"; "SliceIndex" ]
+    fmt "core::slice::index::SliceIndex<core::ops::range::Range<usize>, [@T]>"
+      ~extract_name:(Some "core::slice::index::SliceIndexRangeUsizeSliceTInst")
       ();
     (* core::ops::index::Index<[T; N], I> *)
-    fmt
-      [ "core"; "array"; "[T; N]" ]
-      ~extract_type_name:(Some [ "core"; "array"; "Array" ])
-      [ "core"; "ops"; "index"; "Index" ]
-      ();
+    fmt "core::ops::index::Index<[@T; @N], @I>"
+      ~extract_name:(Some "core::ops::index::IndexArrayInst") ();
     (* core::ops::index::IndexMut<[T; N], I> *)
-    fmt
-      [ "core"; "array"; "[T; N]" ]
-      ~extract_type_name:(Some [ "core"; "array"; "Array" ])
-      [ "core"; "ops"; "index"; "IndexMut" ]
-      ();
+    fmt "core::ops::index::IndexMut<[@T; @N], @I>"
+      ~extract_name:(Some "core::ops::index::IndexMutArrayIInst") ();
     (* core::slice::index::private_slice_index::Sealed<usize> *)
-    fmt
-      [ "core"; "slice"; "index"; "private_slice_index"; "usize" ]
-      [ "core"; "slice"; "index"; "private_slice_index"; "Sealed" ]
-      ();
+    fmt "core::slice::index::private_slice_index::Sealed<usize>"
+      ~extract_name:
+        (Some "core::slice::index::private_slice_index::SealedUsizeInst") ();
     (* core::slice::index::SliceIndex<usize, [T]> *)
-    fmt
-      [ "core"; "slice"; "index"; "usize" ]
-      [ "core"; "slice"; "index"; "SliceIndex" ]
-      ();
-    (* core::ops::index::Index<Vec<T>, T> *)
-    fmt [ "alloc"; "vec"; "Vec" ]
-      [ "core"; "ops"; "index"; "Index" ]
+    fmt "core::slice::index::SliceIndex<usize, [@T]>"
+      ~extract_name:(Some "core::slice::index::SliceIndexUsizeSliceTInst") ();
+    (* core::ops::index::Index<alloc::vec::Vec<T>, T> *)
+    fmt "core::ops::index::Index<alloc::vec::Vec<@T, @A>, @T>"
+      ~extract_name:(Some "alloc::vec::Vec::coreopsindexIndexInst")
       ~filter:(Some [ true; true; false ])
       ();
-    (* core::ops::index::IndexMut<Vec<T>, T> *)
-    fmt [ "alloc"; "vec"; "Vec" ]
-      [ "core"; "ops"; "index"; "IndexMut" ]
+    (* core::ops::index::IndexMut<alloc::vec::Vec<T>, T> *)
+    fmt "core::ops::index::IndexMut<alloc::vec::Vec<@T, @A>, @T>"
+      ~extract_name:(Some "alloc::vec::Vec::coreopsindexIndexMutInst")
       ~filter:(Some [ true; true; false ])
       ();
   ]
 
 let mk_builtin_trait_impls_map () =
-  SimpleNamePairMap.of_list (builtin_trait_impls_info ())
+  let m = NameMatcherMap.of_list (builtin_trait_impls_info ()) in
+  log#ldebug
+    (lazy
+      ("builtin_trait_impls_map:\n"
+      ^ NameMatcherMap.to_string (fun _ -> "...") m));
+  m
 
 let builtin_trait_impls_map = mk_memoized mk_builtin_trait_impls_map
diff --git a/compiler/ExtractName.ml b/compiler/ExtractName.ml
new file mode 100644
index 00000000..41c81207
--- /dev/null
+++ b/compiler/ExtractName.ml
@@ -0,0 +1,105 @@
+(** Utilities for extracting names *)
+
+open Charon.NameMatcher
+
+let log = Logging.extract_log
+
+module NameMatcherMap = struct
+  module NMM = NameMatcherMap
+
+  type 'a t = 'a NMM.t
+
+  let config = { map_vars_to_vars = true }
+
+  let find_opt (ctx : ctx) (name : Types.name) (m : 'a t) : 'a option =
+    NMM.find_opt ctx config name m
+
+  let find_with_generics_opt (ctx : ctx) (name : Types.name)
+      (g : Types.generic_args) (m : 'a t) : 'a option =
+    NMM.find_with_generics_opt ctx config name g m
+
+  let mem (ctx : ctx) (name : Types.name) (m : 'a t) : bool =
+    NMM.mem ctx config name m
+
+  let of_list (ls : (pattern * 'a) list) : 'a t = NMM.of_list ls
+  let to_string = NMM.to_string
+end
+
+(** Helper to convert name patterns to names for extraction.
+
+    For impl blocks, we simply use the name of the type (without its arguments)
+    if all the arguments are variables.
+ *)
+let pattern_to_extract_name (is_trait_impl : bool) (name : pattern) :
+    string list =
+  let c = { tgt = TkName } in
+  let is_var (g : generic_arg) : bool =
+    match g with
+    | GExpr (EVar _) -> true
+    | GRegion (RVar _) -> true
+    | _ -> false
+  in
+  let all_vars = List.for_all is_var in
+  let elem_to_string (e : pattern_elem) : string =
+    match e with
+    | PIdent _ -> pattern_elem_to_string c e
+    | PImpl ty -> (
+        match ty with
+        | EComp id -> (
+            (* Retrieve the last ident *)
+            let id = Collections.List.last id in
+            match id with
+            | PIdent (s, g) ->
+                if all_vars g then s else pattern_elem_to_string c id
+            | PImpl _ -> raise (Failure "Unreachable"))
+        | EPrimAdt (adt, g) ->
+            if all_vars g then
+              match adt with
+              | TTuple ->
+                  let l = List.length g in
+                  if l = 2 then "Pair" else expr_to_string c ty
+              | TArray -> "Array"
+              | TSlice -> "Slice"
+            else expr_to_string c ty
+        | ERef _ | EVar _ -> raise (Failure ""))
+  in
+  let rec pattern_to_string (n : pattern) : string list =
+    match n with
+    | [] -> raise (Failure "Unreachable")
+    | [ e ] ->
+        let e = elem_to_string e in
+        if is_trait_impl then [ e ^ "Inst" ] else [ e ]
+    | e :: n -> elem_to_string e :: pattern_to_string n
+  in
+  pattern_to_string name
+
+let pattern_to_fun_extract_name = pattern_to_extract_name false
+let pattern_to_trait_impl_extract_name = pattern_to_extract_name true
+
+(* TODO: this is provisional. We just want to make sure that the extraction
+   names we derive from the patterns (for the builtin definitions) are
+   consistent with the extraction names we derive from the Rust names *)
+let name_to_simple_name (ctx : ctx) (is_trait_impl : bool) (n : Types.name) :
+    string list =
+  let c : to_pat_config = { tgt = TkName } in
+  pattern_to_extract_name is_trait_impl (name_to_pattern ctx c n)
+
+(** If the [prefix] is Some, we attempt to remove the common prefix
+    between [prefix] and [name] from [name] *)
+let name_with_generics_to_simple_name (ctx : ctx) (is_trait_impl : bool)
+    ?(prefix : Types.name option = None) (name : Types.name)
+    (p : Types.generic_params) (g : Types.generic_args) : string list =
+  let c : to_pat_config = { tgt = TkName } in
+  let name = name_with_generics_to_pattern ctx c name p g in
+  let name =
+    match prefix with
+    | None -> name
+    | Some prefix ->
+        let prefix =
+          name_with_generics_to_pattern ctx c prefix
+            TypesUtils.empty_generic_params TypesUtils.empty_generic_args
+        in
+        let _, _, name = pattern_common_prefix prefix name in
+        name
+  in
+  pattern_to_extract_name is_trait_impl name
diff --git a/compiler/ExtractTypes.ml b/compiler/ExtractTypes.ml
index 77f76bb4..c6212d31 100644
--- a/compiler/ExtractTypes.ml
+++ b/compiler/ExtractTypes.ml
@@ -6,356 +6,88 @@
 open Pure
 open PureUtils
 open TranslateCore
-open ExtractBase
-open StringUtils
 open Config
-module F = Format
+include ExtractBase
 
-(** Small helper to compute the name of an int type *)
-let int_name (int_ty : integer_type) =
-  let isize, usize, i_format, u_format =
-    match !backend with
-    | FStar | Coq | HOL4 ->
-        ("isize", "usize", format_of_string "i%d", format_of_string "u%d")
-    | Lean -> ("Isize", "Usize", format_of_string "I%d", format_of_string "U%d")
-  in
-  match int_ty with
-  | Isize -> isize
-  | I8 -> Printf.sprintf i_format 8
-  | I16 -> Printf.sprintf i_format 16
-  | I32 -> Printf.sprintf i_format 32
-  | I64 -> Printf.sprintf i_format 64
-  | I128 -> Printf.sprintf i_format 128
-  | Usize -> usize
-  | U8 -> Printf.sprintf u_format 8
-  | U16 -> Printf.sprintf u_format 16
-  | U32 -> Printf.sprintf u_format 32
-  | U64 -> Printf.sprintf u_format 64
-  | U128 -> Printf.sprintf u_format 128
-
-(** Small helper to compute the name of a unary operation *)
-let unop_name (unop : unop) : string =
-  match unop with
-  | Not -> (
-      match !backend with FStar | Lean -> "not" | Coq -> "negb" | HOL4 -> "~")
-  | Neg (int_ty : integer_type) -> (
-      match !backend with Lean -> "-" | _ -> int_name int_ty ^ "_neg")
-  | Cast _ ->
-      (* We never directly use the unop name in this case *)
-      raise (Failure "Unsupported")
-
-(** Small helper to compute the name of a binary operation (note that many
-    binary operations like "less than" are extracted to primitive operations,
-    like [<]).
- *)
-let named_binop_name (binop : E.binop) (int_ty : integer_type) : string =
-  let binop =
-    match binop with
-    | Div -> "div"
-    | Rem -> "rem"
-    | Add -> "add"
-    | Sub -> "sub"
-    | Mul -> "mul"
-    | Lt -> "lt"
-    | Le -> "le"
-    | Ge -> "ge"
-    | Gt -> "gt"
-    | BitXor -> "xor"
-    | BitAnd -> "and"
-    | BitOr -> "or"
-    | Shl -> "lsl"
-    | Shr ->
-        "asr"
-        (* NOTE: make sure arithmetic shift right is implemented, i.e. OCaml's asr operator, not lsr *)
-    | _ -> raise (Failure "Unreachable")
-  in
-  (* Remark: the Lean case is actually not used *)
-  match !backend with
-  | Lean -> int_name int_ty ^ "." ^ binop
-  | FStar | Coq | HOL4 -> int_name int_ty ^ "_" ^ binop
+(** Format a constant value.
 
-(** A list of keywords/identifiers used by the backend and with which we
-    want to check collision.
-
-    Remark: this is useful mostly to look for collisions when generating
-    names for *variables*.
+    Inputs:
+    - formatter
+    - [inside]: if [true], the value should be wrapped in parentheses
+      if it is made of an application (ex.: [U32 3])
+    - the constant value
  *)
-let keywords () =
-  let named_unops =
-    unop_name Not
-    :: List.map (fun it -> unop_name (Neg it)) T.all_signed_int_types
-  in
-  let named_binops = [ E.Div; Rem; Add; Sub; Mul ] in
-  let named_binops =
-    List.concat_map
-      (fun bn -> List.map (fun it -> named_binop_name bn it) T.all_int_types)
-      named_binops
-  in
-  let misc =
-    match !backend with
-    | FStar ->
-        [
-          "assert";
-          "assert_norm";
-          "assume";
-          "else";
-          "fun";
-          "fn";
-          "FStar";
-          "FStar.Mul";
-          "if";
-          "in";
-          "include";
-          "int";
-          "let";
-          "list";
-          "match";
-          "open";
-          "rec";
-          "scalar_cast";
-          "then";
-          "type";
-          "Type0";
-          "Type";
-          "unit";
-          "val";
-          "with";
-        ]
-    | Coq ->
-        [
-          "assert";
-          "Arguments";
-          "Axiom";
-          "char_of_byte";
-          "Check";
-          "Declare";
-          "Definition";
-          "else";
-          "End";
-          "fun";
-          "Fixpoint";
-          "if";
-          "in";
-          "int";
-          "Inductive";
-          "Import";
-          "let";
-          "Lemma";
-          "match";
-          "Module";
-          "not";
-          "Notation";
-          "Proof";
-          "Qed";
-          "rec";
-          "Record";
-          "Require";
-          "Scope";
-          "Search";
-          "SearchPattern";
-          "Set";
-          "then";
-          (* [tt] is unit *)
-          "tt";
-          "type";
-          "Type";
-          "unit";
-          "with";
-        ]
-    | Lean ->
-        [
-          "by";
-          "class";
-          "decreasing_by";
-          "def";
-          "deriving";
-          "do";
-          "else";
-          "end";
-          "for";
-          "have";
-          "if";
-          "inductive";
-          "instance";
-          "import";
-          "let";
-          "macro";
-          "match";
-          "namespace";
-          "opaque";
-          "open";
-          "run_cmd";
-          "set_option";
-          "simp";
-          "structure";
-          "syntax";
-          "termination_by";
-          "then";
-          "Type";
-          "unsafe";
-          "where";
-          "with";
-          "opaque_defs";
-        ]
-    | HOL4 ->
-        [
-          "Axiom";
-          "case";
-          "Definition";
-          "else";
-          "End";
-          "fix";
-          "fix_exec";
-          "fn";
-          "fun";
-          "if";
-          "in";
-          "int";
-          "Inductive";
-          "let";
-          "of";
-          "Proof";
-          "QED";
-          "then";
-          "Theorem";
-        ]
-  in
-  List.concat [ named_unops; named_binops; misc ]
-
-let assumed_adts () : (assumed_ty * string) list =
-  match !backend with
-  | Lean ->
-      [
-        (State, "State");
-        (Result, "Result");
-        (Error, "Error");
-        (Fuel, "Nat");
-        (Array, "Array");
-        (Slice, "Slice");
-        (Str, "Str");
-        (RawPtr Mut, "MutRawPtr");
-        (RawPtr Const, "ConstRawPtr");
-      ]
-  | Coq | FStar | HOL4 ->
-      [
-        (State, "state");
-        (Result, "result");
-        (Error, "error");
-        (Fuel, if !backend = HOL4 then "num" else "nat");
-        (Array, "array");
-        (Slice, "slice");
-        (Str, "str");
-        (RawPtr Mut, "mut_raw_ptr");
-        (RawPtr Const, "const_raw_ptr");
-      ]
-
-let assumed_struct_constructors () : (assumed_ty * string) list =
-  match !backend with
-  | Lean -> [ (Array, "Array.make") ]
-  | Coq -> [ (Array, "mk_array") ]
-  | FStar -> [ (Array, "mk_array") ]
-  | HOL4 -> [ (Array, "mk_array") ]
+let extract_literal (fmt : F.formatter) (inside : bool) (cv : literal) : unit =
+  match cv with
+  | VScalar sv -> (
+      match !backend with
+      | FStar -> F.pp_print_string fmt (Z.to_string sv.value)
+      | Coq | HOL4 | Lean ->
+          let print_brackets = inside && !backend = HOL4 in
+          if print_brackets then F.pp_print_string fmt "(";
+          (match !backend with
+          | Coq | Lean -> ()
+          | HOL4 ->
+              F.pp_print_string fmt ("int_to_" ^ int_name sv.int_ty);
+              F.pp_print_space fmt ()
+          | _ -> raise (Failure "Unreachable"));
+          (* We need to add parentheses if the value is negative *)
+          if sv.value >= Z.of_int 0 then
+            F.pp_print_string fmt (Z.to_string sv.value)
+          else if !backend = Lean then
+            (* TODO: parsing issues with Lean because there are ambiguous
+               interpretations between int values and nat values *)
+            F.pp_print_string fmt
+              ("(-(" ^ Z.to_string (Z.neg sv.value) ^ ":Int))")
+          else F.pp_print_string fmt ("(" ^ Z.to_string sv.value ^ ")");
+          (match !backend with
+          | Coq ->
+              let iname = int_name sv.int_ty in
+              F.pp_print_string fmt ("%" ^ iname)
+          | Lean ->
+              let iname = String.lowercase_ascii (int_name sv.int_ty) in
+              F.pp_print_string fmt ("#" ^ iname)
+          | HOL4 -> ()
+          | _ -> raise (Failure "Unreachable"));
+          if print_brackets then F.pp_print_string fmt ")")
+  | VBool b ->
+      let b =
+        match !backend with
+        | HOL4 -> if b then "T" else "F"
+        | Coq | FStar | Lean -> if b then "true" else "false"
+      in
+      F.pp_print_string fmt b
+  | VChar c -> (
+      match !backend with
+      | HOL4 ->
+          (* [#"a"] is a notation for [CHR 97] (97 is the ASCII code for 'a') *)
+          F.pp_print_string fmt ("#\"" ^ String.make 1 c ^ "\"")
+      | FStar | Lean -> F.pp_print_string fmt ("'" ^ String.make 1 c ^ "'")
+      | Coq ->
+          if inside then F.pp_print_string fmt "(";
+          F.pp_print_string fmt "char_of_byte";
+          F.pp_print_space fmt ();
+          (* Convert the the char to ascii *)
+          let c =
+            let i = Char.code c in
+            let x0 = i / 16 in
+            let x1 = i mod 16 in
+            "Coq.Init.Byte.x" ^ string_of_int x0 ^ string_of_int x1
+          in
+          F.pp_print_string fmt c;
+          if inside then F.pp_print_string fmt ")")
 
-let assumed_variants () : (assumed_ty * VariantId.id * string) list =
-  match !backend with
-  | FStar ->
-      [
-        (Result, result_return_id, "Return");
-        (Result, result_fail_id, "Fail");
-        (Error, error_failure_id, "Failure");
-        (Error, error_out_of_fuel_id, "OutOfFuel");
-        (* No Fuel::Zero on purpose *)
-        (* No Fuel::Succ on purpose *)
-      ]
-  | Coq ->
-      [
-        (Result, result_return_id, "Return");
-        (Result, result_fail_id, "Fail_");
-        (Error, error_failure_id, "Failure");
-        (Error, error_out_of_fuel_id, "OutOfFuel");
-        (Fuel, fuel_zero_id, "O");
-        (Fuel, fuel_succ_id, "S");
-      ]
-  | Lean ->
-      [
-        (Result, result_return_id, "ret");
-        (Result, result_fail_id, "fail");
-        (Error, error_failure_id, "panic");
-        (* No Fuel::Zero on purpose *)
-        (* No Fuel::Succ on purpose *)
-      ]
-  | HOL4 ->
-      [
-        (Result, result_return_id, "Return");
-        (Result, result_fail_id, "Fail");
-        (Error, error_failure_id, "Failure");
-        (* No Fuel::Zero on purpose *)
-        (* No Fuel::Succ on purpose *)
-      ]
-
-let assumed_llbc_functions () :
-    (A.assumed_fun_id * T.RegionGroupId.id option * string) list =
-  let rg0 = Some T.RegionGroupId.zero in
-  match !backend with
-  | FStar | Coq | HOL4 ->
-      [
-        (ArrayIndexShared, None, "array_index_usize");
-        (ArrayIndexMut, None, "array_index_usize");
-        (ArrayIndexMut, rg0, "array_update_usize");
-        (ArrayToSliceShared, None, "array_to_slice");
-        (ArrayToSliceMut, None, "array_to_slice");
-        (ArrayToSliceMut, rg0, "array_from_slice");
-        (ArrayRepeat, None, "array_repeat");
-        (SliceIndexShared, None, "slice_index_usize");
-        (SliceIndexMut, None, "slice_index_usize");
-        (SliceIndexMut, rg0, "slice_update_usize");
-        (SliceLen, None, "slice_len");
-      ]
-  | Lean ->
-      [
-        (ArrayIndexShared, None, "Array.index_usize");
-        (ArrayIndexMut, None, "Array.index_usize");
-        (ArrayIndexMut, rg0, "Array.update_usize");
-        (ArrayToSliceShared, None, "Array.to_slice");
-        (ArrayToSliceMut, None, "Array.to_slice");
-        (ArrayToSliceMut, rg0, "Array.from_slice");
-        (ArrayRepeat, None, "Array.repeat");
-        (SliceIndexShared, None, "Slice.index_usize");
-        (SliceIndexMut, None, "Slice.index_usize");
-        (SliceIndexMut, rg0, "Slice.update_usize");
-        (SliceLen, None, "Slice.len");
-      ]
-
-let assumed_pure_functions () : (pure_assumed_fun_id * string) list =
-  match !backend with
-  | FStar ->
-      [
-        (Return, "return");
-        (Fail, "fail");
-        (Assert, "massert");
-        (FuelDecrease, "decrease");
-        (FuelEqZero, "is_zero");
-      ]
-  | Coq ->
-      (* We don't provide [FuelDecrease] and [FuelEqZero] on purpose *)
-      [ (Return, "return_"); (Fail, "fail_"); (Assert, "massert") ]
-  | Lean ->
-      (* We don't provide [FuelDecrease] and [FuelEqZero] on purpose *)
-      [ (Return, "return"); (Fail, "fail_"); (Assert, "massert") ]
-  | HOL4 ->
-      (* We don't provide [FuelDecrease] and [FuelEqZero] on purpose *)
-      [ (Return, "return"); (Fail, "fail"); (Assert, "massert") ]
-
-let names_map_init () : names_map_init =
-  {
-    keywords = keywords ();
-    assumed_adts = assumed_adts ();
-    assumed_structs = assumed_struct_constructors ();
-    assumed_variants = assumed_variants ();
-    assumed_llbc_functions = assumed_llbc_functions ();
-    assumed_pure_functions = assumed_pure_functions ();
-  }
+(** Format a unary operation
 
+    Inputs:
+    - a formatter for expressions (called on the argument of the unop)
+    - extraction context (see below)
+    - formatter
+    - expression formatter
+    - [inside]
+    - unop
+    - argument
+ *)
 let extract_unop (extract_expr : bool -> texpression -> unit)
     (fmt : F.formatter) (inside : bool) (unop : unop) (arg : texpression) : unit
     =
@@ -411,7 +143,18 @@ let extract_unop (extract_expr : bool -> texpression -> unit)
           extract_expr true arg;
           if inside then F.pp_print_string fmt ")")
 
-(** [extract_expr] : the boolean argument is [inside] *)
+(** Format a binary operation
+
+    Inputs:
+    - a formatter for expressions (called on the arguments of the binop)
+    - extraction context (see below)
+    - formatter
+    - expression formatter
+    - [inside]
+    - binop
+    - argument 0
+    - argument 1
+ *)
 let extract_binop (extract_expr : bool -> texpression -> unit)
     (fmt : F.formatter) (inside : bool) (binop : E.binop)
     (int_ty : integer_type) (arg0 : texpression) (arg1 : texpression) : unit =
@@ -453,518 +196,6 @@ let extract_binop (extract_expr : bool -> texpression -> unit)
       extract_expr true arg1);
   if inside then F.pp_print_string fmt ")"
 
-let type_decl_kind_to_qualif (kind : decl_kind)
-    (type_kind : type_decl_kind option) : string option =
-  match !backend with
-  | FStar -> (
-      match kind with
-      | SingleNonRec -> Some "type"
-      | SingleRec -> Some "type"
-      | MutRecFirst -> Some "type"
-      | MutRecInner -> Some "and"
-      | MutRecLast -> Some "and"
-      | Assumed -> Some "assume type"
-      | Declared -> Some "val")
-  | Coq -> (
-      match (kind, type_kind) with
-      | SingleNonRec, Some Enum -> Some "Inductive"
-      | SingleNonRec, Some Struct -> Some "Record"
-      | (SingleRec | MutRecFirst), Some _ -> Some "Inductive"
-      | (MutRecInner | MutRecLast), Some _ ->
-          (* Coq doesn't support groups of mutually recursive definitions which mix
-           * records and inducties: we convert everything to records if this happens
-           *)
-          Some "with"
-      | (Assumed | Declared), None -> Some "Axiom"
-      | SingleNonRec, None ->
-          (* This is for traits *)
-          Some "Record"
-      | _ ->
-          raise
-            (Failure
-               ("Unexpected: (" ^ show_decl_kind kind ^ ", "
-               ^ Print.option_to_string show_type_decl_kind type_kind
-               ^ ")")))
-  | Lean -> (
-      match kind with
-      | SingleNonRec ->
-          if type_kind = Some Struct then Some "structure" else Some "inductive"
-      | SingleRec -> Some "inductive"
-      | MutRecFirst -> Some "inductive"
-      | MutRecInner -> Some "inductive"
-      | MutRecLast -> Some "inductive"
-      | Assumed -> Some "axiom"
-      | Declared -> Some "axiom")
-  | HOL4 -> None
-
-let fun_decl_kind_to_qualif (kind : decl_kind) : string option =
-  match !backend with
-  | FStar -> (
-      match kind with
-      | SingleNonRec -> Some "let"
-      | SingleRec -> Some "let rec"
-      | MutRecFirst -> Some "let rec"
-      | MutRecInner -> Some "and"
-      | MutRecLast -> Some "and"
-      | Assumed -> Some "assume val"
-      | Declared -> Some "val")
-  | Coq -> (
-      match kind with
-      | SingleNonRec -> Some "Definition"
-      | SingleRec -> Some "Fixpoint"
-      | MutRecFirst -> Some "Fixpoint"
-      | MutRecInner -> Some "with"
-      | MutRecLast -> Some "with"
-      | Assumed -> Some "Axiom"
-      | Declared -> Some "Axiom")
-  | Lean -> (
-      match kind with
-      | SingleNonRec -> Some "def"
-      | SingleRec -> Some "divergent def"
-      | MutRecFirst -> Some "mutual divergent def"
-      | MutRecInner -> Some "divergent def"
-      | MutRecLast -> Some "divergent def"
-      | Assumed -> Some "axiom"
-      | Declared -> Some "axiom")
-  | HOL4 -> None
-
-(** The type of types.
-
-    TODO: move inside the formatter?
- *)
-let type_keyword () =
-  match !backend with
-  | FStar -> "Type0"
-  | Coq | Lean -> "Type"
-  | HOL4 -> raise (Failure "Unexpected")
-
-(**
-   [ctx]: we use the context to lookup type definitions, to retrieve type names.
-   This is used to compute variable names, when they have no basenames: in this
-   case we use the first letter of the type name.
-
-   [variant_concatenate_type_name]: if true, add the type name as a prefix
-   to the variant names.
-   Ex.:
-   In Rust:
-     {[
-       enum List = {
-         Cons(u32, Box<List>),x
-         Nil,
-       }
-     ]}
-
-   F*, if option activated:
-     {[
-       type list =
-       | ListCons : u32 -> list -> list
-       | ListNil : list
-     ]}
-
-   F*, if option not activated:
-     {[
-       type list =
-       | Cons : u32 -> list -> list
-       | Nil : list
-     ]}
-
-   Rk.: this should be true by default, because in Rust all the variant names
-   are actively uniquely identifier by the type name [List::Cons(...)], while
-   in other languages it is not necessarily the case, and thus clashes can mess
-   up type checking. Note that some languages actually forbids the name clashes
-   (it is the case of F* ).
- *)
-let mk_formatter (ctx : trans_ctx) (crate_name : string)
-    (variant_concatenate_type_name : bool) : formatter =
-  let int_name = int_name in
-
-  (* Prepare a name.
-   * The first id elem is always the crate: if it is the local crate,
-   * we remove it.
-   * We also remove all the disambiguators, then convert everything to strings.
-   * **Rmk:** because we remove the disambiguators, there may be name collisions
-   * (which is ok, because we check for name collisions and fail if there is any).
-   *)
-  let get_name (name : name) : string list =
-    (* Rmk.: initially we only filtered the disambiguators equal to 0 *)
-    let name = Names.filter_disambiguators name in
-    match name with
-    | Ident crate :: name ->
-        let name = if crate = crate_name then name else Ident crate :: name in
-        let name =
-          List.map
-            (function
-              | Names.Ident s -> s
-              | Disambiguator d -> Names.Disambiguator.to_string d)
-            name
-        in
-        name
-    | _ ->
-        raise (Failure ("Unexpected name shape: " ^ Print.name_to_string name))
-  in
-  let flatten_name (name : string list) : string =
-    match !backend with
-    | FStar | Coq | HOL4 -> String.concat "_" name
-    | Lean -> String.concat "." name
-  in
-  let get_type_name = get_name in
-  let get_type_name_no_suffix name =
-    match !backend with
-    | FStar | Coq | HOL4 -> String.concat "_" (get_type_name name)
-    | Lean -> String.concat "." (get_type_name name)
-  in
-  let type_name name =
-    match !backend with
-    | FStar ->
-        StringUtils.lowercase_first_letter (get_type_name_no_suffix name ^ "_t")
-    | Coq | HOL4 -> get_type_name_no_suffix name ^ "_t"
-    | Lean -> get_type_name_no_suffix name
-  in
-  let field_name (def_name : name) (field_id : FieldId.id)
-      (field_name : string option) : string =
-    let field_name_s =
-      match field_name with
-      | Some field_name -> field_name
-      | None ->
-          (* TODO: extract structs with no field names to tuples *)
-          FieldId.to_string field_id
-    in
-    if !Config.record_fields_short_names then
-      if field_name = None then (* TODO: this is a bit ugly *)
-        "_" ^ field_name_s
-      else field_name_s
-    else
-      let def_name = get_type_name_no_suffix def_name ^ "_" ^ field_name_s in
-      match !backend with
-      | Lean | HOL4 -> def_name
-      | Coq | FStar -> StringUtils.lowercase_first_letter def_name
-  in
-  let variant_name (def_name : name) (variant : string) : string =
-    match !backend with
-    | FStar | Coq | HOL4 ->
-        let variant = to_camel_case variant in
-        if variant_concatenate_type_name then
-          StringUtils.capitalize_first_letter
-            (get_type_name_no_suffix def_name ^ "_" ^ variant)
-        else variant
-    | Lean -> variant
-  in
-  let struct_constructor (basename : name) : string =
-    let tname = type_name basename in
-    ExtractBuiltin.mk_struct_constructor tname
-  in
-  let get_fun_name fname =
-    let fname = get_name fname in
-    (* TODO: don't convert to snake case for Coq, HOL4, F* *)
-    let fname = flatten_name fname in
-    match !backend with
-    | FStar | Coq | HOL4 -> StringUtils.lowercase_first_letter fname
-    | Lean -> fname
-  in
-  let global_name (name : global_name) : string =
-    (* Converting to snake case also lowercases the letters (in Rust, global
-     * names are written in capital letters). *)
-    let parts = List.map to_snake_case (get_name name) in
-    String.concat "_" parts
-  in
-  let fun_name (fname : fun_name) (num_loops : int) (loop_id : LoopId.id option)
-      (num_rgs : int) (rg : region_group_info option) (filter_info : bool * int)
-      : string =
-    let fname = get_fun_name fname in
-    (* Compute the suffix *)
-    let suffix = default_fun_suffix num_loops loop_id num_rgs rg filter_info in
-    (* Concatenate *)
-    fname ^ suffix
-  in
-
-  let trait_decl_name (trait_decl : trait_decl) : string =
-    type_name trait_decl.name
-  in
-
-  let trait_impl_name (trait_decl : trait_decl) (trait_impl : trait_impl) :
-      string =
-    (* TODO: provisional: we concatenate the trait impl name (which is its type)
-       with the trait decl name *)
-    let trait_decl =
-      let name = trait_decl.name in
-      let name = get_type_name_no_suffix name ^ "Inst" in
-      (* Remove the occurrences of '.' *)
-      String.concat "" (String.split_on_char '.' name)
-    in
-    let name = flatten_name (get_type_name trait_impl.name @ [ trait_decl ]) in
-    match !backend with
-    | FStar -> StringUtils.lowercase_first_letter name
-    | Coq | HOL4 | Lean -> name
-  in
-
-  let trait_decl_constructor (trait_decl : trait_decl) : string =
-    let name = trait_decl_name trait_decl in
-    ExtractBuiltin.mk_struct_constructor name
-  in
-
-  let trait_parent_clause_name (trait_decl : trait_decl) (clause : trait_clause)
-      : string =
-    (* TODO: improve - it would be better to not use indices *)
-    let clause = "parent_clause_" ^ TraitClauseId.to_string clause.clause_id in
-    if !Config.record_fields_short_names then clause
-    else trait_decl_name trait_decl ^ "_" ^ clause
-  in
-  let trait_type_name (trait_decl : trait_decl) (item : string) : string =
-    let name =
-      if !Config.record_fields_short_names then item
-      else trait_decl_name trait_decl ^ "_" ^ item
-    in
-    (* Constants are usually all capital letters.
-       Some backends do not support field names starting with a capital letter,
-       and it may be weird to lowercase everything (especially as it may lead
-       to more name collisions): we add a prefix when necessary.
-       For instance, it gives: "U" -> "tU"
-       Note that for some backends we prepend the type name (because those backends
-       can't disambiguate fields coming from different ADTs if they have the same
-       names), and thus don't need to add a prefix starting with a lowercase.
-    *)
-    match !backend with FStar -> "t" ^ name | Coq | Lean | HOL4 -> name
-  in
-  let trait_const_name (trait_decl : trait_decl) (item : string) : string =
-    let name =
-      if !Config.record_fields_short_names then item
-      else trait_decl_name trait_decl ^ "_" ^ item
-    in
-    (* See [trait_type_name] *)
-    match !backend with FStar -> "c" ^ name | Coq | Lean | HOL4 -> name
-  in
-  let trait_method_name (trait_decl : trait_decl) (item : string) : string =
-    if !Config.record_fields_short_names then item
-    else trait_decl_name trait_decl ^ "_" ^ item
-  in
-  let trait_type_clause_name (trait_decl : trait_decl) (item : string)
-      (clause : trait_clause) : string =
-    (* TODO: improve - it would be better to not use indices *)
-    trait_type_name trait_decl item
-    ^ "_clause_"
-    ^ TraitClauseId.to_string clause.clause_id
-  in
-
-  let termination_measure_name (_fid : A.FunDeclId.id) (fname : fun_name)
-      (num_loops : int) (loop_id : LoopId.id option) : string =
-    let fname = get_fun_name fname in
-    let lp_suffix = default_fun_loop_suffix num_loops loop_id in
-    (* Compute the suffix *)
-    let suffix =
-      match !Config.backend with
-      | FStar -> "_decreases"
-      | Lean -> "_terminates"
-      | Coq | HOL4 -> raise (Failure "Unexpected")
-    in
-    (* Concatenate *)
-    fname ^ lp_suffix ^ suffix
-  in
-
-  let decreases_proof_name (_fid : A.FunDeclId.id) (fname : fun_name)
-      (num_loops : int) (loop_id : LoopId.id option) : string =
-    let fname = get_fun_name fname in
-    let lp_suffix = default_fun_loop_suffix num_loops loop_id in
-    (* Compute the suffix *)
-    let suffix =
-      match !Config.backend with
-      | Lean -> "_decreases"
-      | FStar | Coq | HOL4 -> raise (Failure "Unexpected")
-    in
-    (* Concatenate *)
-    fname ^ lp_suffix ^ suffix
-  in
-
-  let var_basename (_varset : StringSet.t) (basename : string option) (ty : ty)
-      : string =
-    (* Small helper to derive var names from ADT type names.
-
-       We do the following:
-       - convert the type name to snake case
-       - take the first letter of every "letter group"
-       Ex.: "HashMap" -> "hash_map" -> "hm"
-    *)
-    let name_from_type_ident (name : string) : string =
-      let cl = to_snake_case name in
-      let cl = String.split_on_char '_' cl in
-      let cl = List.filter (fun s -> String.length s > 0) cl in
-      assert (List.length cl > 0);
-      let cl = List.map (fun s -> s.[0]) cl in
-      StringUtils.string_of_chars cl
-    in
-    (* If there is a basename, we use it *)
-    match basename with
-    | Some basename ->
-        (* This should be a no-op *)
-        to_snake_case basename
-    | None -> (
-        (* No basename: we use the first letter of the type *)
-        match ty with
-        | Adt (type_id, generics) -> (
-            match type_id with
-            | Tuple ->
-                (* The "pair" case is frequent enough to have its special treatment *)
-                if List.length generics.types = 2 then "p" else "t"
-            | Assumed Result -> "r"
-            | Assumed Error -> ConstStrings.error_basename
-            | Assumed Fuel -> ConstStrings.fuel_basename
-            | Assumed Array -> "a"
-            | Assumed Slice -> "s"
-            | Assumed Str -> "s"
-            | Assumed State -> ConstStrings.state_basename
-            | Assumed (RawPtr _) -> "p"
-            | AdtId adt_id ->
-                let def = TypeDeclId.Map.find adt_id ctx.type_ctx.type_decls in
-                (* Derive the var name from the last ident of the type name
-                 * Ex.: ["hashmap"; "HashMap"] ~~> "HashMap" -> "hash_map" -> "hm"
-                 *)
-                (* The name shouldn't be empty, and its last element should
-                 * be an ident *)
-                let cl = List.nth def.name (List.length def.name - 1) in
-                name_from_type_ident (Names.as_ident cl))
-        | TypeVar _ -> (
-            (* TODO: use "t" also for F* *)
-            match !backend with
-            | FStar -> "x" (* lacking inspiration here... *)
-            | Coq | Lean | HOL4 -> "t" (* lacking inspiration here... *))
-        | Literal lty -> (
-            match lty with Bool -> "b" | Char -> "c" | Integer _ -> "i")
-        | Arrow _ -> "f"
-        | TraitType (_, _, name) -> name_from_type_ident name)
-  in
-  let type_var_basename (_varset : StringSet.t) (basename : string) : string =
-    (* Rust type variables are snake-case and start with a capital letter *)
-    match !backend with
-    | FStar ->
-        (* This is *not* a no-op: this removes the capital letter *)
-        to_snake_case basename
-    | HOL4 ->
-        (* In HOL4, type variable names must start with "'" *)
-        "'" ^ to_snake_case basename
-    | Coq | Lean -> basename
-  in
-  let const_generic_var_basename (_varset : StringSet.t) (basename : string) :
-      string =
-    (* Rust type variables are snake-case and start with a capital letter *)
-    match !backend with
-    | FStar | HOL4 ->
-        (* This is *not* a no-op: this removes the capital letter *)
-        to_snake_case basename
-    | Coq | Lean -> basename
-  in
-  let trait_clause_basename (_varset : StringSet.t) (_clause : trait_clause) :
-      string =
-    (* TODO: actually use the clause to derive the name *)
-    "inst"
-  in
-  let trait_self_clause_basename = "self_clause" in
-  let append_index (basename : string) (i : int) : string =
-    basename ^ string_of_int i
-  in
-
-  let extract_literal (fmt : F.formatter) (inside : bool) (cv : literal) : unit
-      =
-    match cv with
-    | Scalar sv -> (
-        match !backend with
-        | FStar -> F.pp_print_string fmt (Z.to_string sv.PV.value)
-        | Coq | HOL4 | Lean ->
-            let print_brackets = inside && !backend = HOL4 in
-            if print_brackets then F.pp_print_string fmt "(";
-            (match !backend with
-            | Coq | Lean -> ()
-            | HOL4 ->
-                F.pp_print_string fmt ("int_to_" ^ int_name sv.PV.int_ty);
-                F.pp_print_space fmt ()
-            | _ -> raise (Failure "Unreachable"));
-            (* We need to add parentheses if the value is negative *)
-            if sv.PV.value >= Z.of_int 0 then
-              F.pp_print_string fmt (Z.to_string sv.PV.value)
-            else if !backend = Lean then
-              (* TODO: parsing issues with Lean because there are ambiguous
-                 interpretations between int values and nat values *)
-              F.pp_print_string fmt
-                ("(-(" ^ Z.to_string (Z.neg sv.PV.value) ^ ":Int))")
-            else F.pp_print_string fmt ("(" ^ Z.to_string sv.PV.value ^ ")");
-            (match !backend with
-            | Coq ->
-                let iname = int_name sv.PV.int_ty in
-                F.pp_print_string fmt ("%" ^ iname)
-            | Lean ->
-                let iname = String.lowercase_ascii (int_name sv.PV.int_ty) in
-                F.pp_print_string fmt ("#" ^ iname)
-            | HOL4 -> ()
-            | _ -> raise (Failure "Unreachable"));
-            if print_brackets then F.pp_print_string fmt ")")
-    | Bool b ->
-        let b =
-          match !backend with
-          | HOL4 -> if b then "T" else "F"
-          | Coq | FStar | Lean -> if b then "true" else "false"
-        in
-        F.pp_print_string fmt b
-    | Char c -> (
-        match !backend with
-        | HOL4 ->
-            (* [#"a"] is a notation for [CHR 97] (97 is the ASCII code for 'a') *)
-            F.pp_print_string fmt ("#\"" ^ String.make 1 c ^ "\"")
-        | FStar | Lean -> F.pp_print_string fmt ("'" ^ String.make 1 c ^ "'")
-        | Coq ->
-            if inside then F.pp_print_string fmt "(";
-            F.pp_print_string fmt "char_of_byte";
-            F.pp_print_space fmt ();
-            (* Convert the the char to ascii *)
-            let c =
-              let i = Char.code c in
-              let x0 = i / 16 in
-              let x1 = i mod 16 in
-              "Coq.Init.Byte.x" ^ string_of_int x0 ^ string_of_int x1
-            in
-            F.pp_print_string fmt c;
-            if inside then F.pp_print_string fmt ")")
-  in
-  let bool_name = if !backend = Lean then "Bool" else "bool" in
-  let char_name = if !backend = Lean then "Char" else "char" in
-  let str_name = if !backend = Lean then "String" else "string" in
-  {
-    bool_name;
-    char_name;
-    int_name;
-    str_name;
-    type_decl_kind_to_qualif;
-    fun_decl_kind_to_qualif;
-    field_name;
-    variant_name;
-    struct_constructor;
-    type_name;
-    global_name;
-    fun_name;
-    termination_measure_name;
-    decreases_proof_name;
-    trait_decl_name;
-    trait_impl_name;
-    trait_decl_constructor;
-    trait_parent_clause_name;
-    trait_const_name;
-    trait_type_name;
-    trait_method_name;
-    trait_type_clause_name;
-    var_basename;
-    type_var_basename;
-    const_generic_var_basename;
-    trait_self_clause_basename;
-    trait_clause_basename;
-    append_index;
-    extract_literal;
-    extract_unop;
-    extract_binop;
-  }
-
-let mk_formatter_and_names_maps (ctx : trans_ctx) (crate_name : string)
-    (variant_concatenate_type_name : bool) : formatter * names_maps =
-  let fmt = mk_formatter ctx crate_name variant_concatenate_type_name in
-  let names_maps = initialize_names_maps fmt (names_map_init ()) in
-  (fmt, names_maps)
-
 let is_single_opaque_fun_decl_group (dg : Pure.fun_decl list) : bool =
   match dg with [ d ] -> d.body = None | _ -> false
 
@@ -1119,20 +350,20 @@ let extract_arrow (fmt : F.formatter) () : unit =
 let extract_const_generic (ctx : extraction_ctx) (fmt : F.formatter)
     (inside : bool) (cg : const_generic) : unit =
   match cg with
-  | ConstGenericGlobal id ->
+  | CgGlobal id ->
       let s = ctx_get_global id ctx in
       F.pp_print_string fmt s
-  | ConstGenericValue v -> ctx.fmt.extract_literal fmt inside v
-  | ConstGenericVar id ->
+  | CgValue v -> extract_literal fmt inside v
+  | CgVar id ->
       let s = ctx_get_const_generic_var id ctx in
       F.pp_print_string fmt s
 
-let extract_literal_type (ctx : extraction_ctx) (fmt : F.formatter)
+let extract_literal_type (_ctx : extraction_ctx) (fmt : F.formatter)
     (ty : literal_type) : unit =
   match ty with
-  | Bool -> F.pp_print_string fmt ctx.fmt.bool_name
-  | Char -> F.pp_print_string fmt ctx.fmt.char_name
-  | Integer int_ty -> F.pp_print_string fmt (ctx.fmt.int_name int_ty)
+  | TBool -> F.pp_print_string fmt (bool_name ())
+  | TChar -> F.pp_print_string fmt (char_name ())
+  | TInteger int_ty -> F.pp_print_string fmt (int_name int_ty)
 
 (** [inside] constrols whether we should add parentheses or not around type
     applications (if [true] we add parentheses).
@@ -1158,10 +389,10 @@ let rec extract_ty (ctx : extraction_ctx) (fmt : F.formatter)
     (no_params_tys : TypeDeclId.Set.t) (inside : bool) (ty : ty) : unit =
   let extract_rec = extract_ty ctx fmt no_params_tys in
   match ty with
-  | Adt (type_id, generics) -> (
+  | TAdt (type_id, generics) -> (
       let has_params = generics <> empty_generic_args in
       match type_id with
-      | Tuple ->
+      | TTuple ->
           (* This is a bit annoying, but in F*/Coq/HOL4 [()] is not the unit type:
            * we have to write [unit]... *)
           if generics.types = [] then F.pp_print_string fmt (unit_name ())
@@ -1181,7 +412,7 @@ let rec extract_ty (ctx : extraction_ctx) (fmt : F.formatter)
                 F.pp_print_space fmt ())
               (extract_rec true) generics.types;
             F.pp_print_string fmt ")")
-      | AdtId _ | Assumed _ -> (
+      | TAdtId _ | TAssumed _ -> (
           (* HOL4 behaves differently. Where in Coq/FStar/Lean we would write:
              `tree a b`
 
@@ -1200,7 +431,7 @@ let rec extract_ty (ctx : extraction_ctx) (fmt : F.formatter)
                  argument for `Vec`). *)
               let generics =
                 match type_id with
-                | AdtId id -> (
+                | TAdtId id -> (
                     match
                       TypeDeclId.Map.find_opt id ctx.types_filter_type_args_map
                     with
@@ -1223,8 +454,8 @@ let rec extract_ty (ctx : extraction_ctx) (fmt : F.formatter)
               assert (const_generics = []);
               let print_tys =
                 match type_id with
-                | AdtId id -> not (TypeDeclId.Set.mem id no_params_tys)
-                | Assumed _ -> true
+                | TAdtId id -> not (TypeDeclId.Set.mem id no_params_tys)
+                | TAssumed _ -> true
                 | _ -> raise (Failure "Unreachable")
               in
               if types <> [] && print_tys then (
@@ -1243,9 +474,9 @@ let rec extract_ty (ctx : extraction_ctx) (fmt : F.formatter)
                 Collections.List.iter_link (F.pp_print_space fmt)
                   (extract_trait_ref ctx fmt no_params_tys true)
                   trait_refs)))
-  | TypeVar vid -> F.pp_print_string fmt (ctx_get_type_var vid ctx)
-  | Literal lty -> extract_literal_type ctx fmt lty
-  | Arrow (arg_ty, ret_ty) ->
+  | TVar vid -> F.pp_print_string fmt (ctx_get_type_var vid ctx)
+  | TLiteral lty -> extract_literal_type ctx fmt lty
+  | TArrow (arg_ty, ret_ty) ->
       if inside then F.pp_print_string fmt "(";
       extract_rec false arg_ty;
       F.pp_print_space fmt ();
@@ -1253,7 +484,7 @@ let rec extract_ty (ctx : extraction_ctx) (fmt : F.formatter)
       F.pp_print_space fmt ();
       extract_rec false ret_ty;
       if inside then F.pp_print_string fmt ")"
-  | TraitType (trait_ref, generics, type_name) -> (
+  | TTraitType (trait_ref, generics, type_name) -> (
       if !parameterize_trait_types then raise (Failure "Unimplemented")
       else
         let type_name =
@@ -1426,8 +657,9 @@ let extract_type_decl_register_names (ctx : extraction_ctx) (def : type_decl) :
     extraction_ctx =
   (* Lookup the builtin information, if there is *)
   let open ExtractBuiltin in
-  let sname = name_to_simple_name def.name in
-  let info = SimpleNameMap.find_opt sname (builtin_types_map ()) in
+  let info =
+    match_name_find_opt ctx.trans_ctx def.llbc_name (builtin_types_map ())
+  in
   (* Register the filtering information, if there is *)
   let ctx =
     match info with
@@ -1442,10 +674,10 @@ let extract_type_decl_register_names (ctx : extraction_ctx) (def : type_decl) :
   (* Compute and register the type def name *)
   let def_name =
     match info with
-    | None -> ctx.fmt.type_name def.name
+    | None -> ctx_compute_type_name ctx def.llbc_name
     | Some info -> info.extract_name
   in
-  let ctx = ctx_add (TypeId (AdtId def.def_id)) def_name ctx in
+  let ctx = ctx_add (TypeId (TAdtId def.def_id)) def_name ctx in
   (* Compute and register:
    * - the variant names, if this is an enumeration
    * - the field names, if this is a structure
@@ -1460,10 +692,14 @@ let extract_type_decl_register_names (ctx : extraction_ctx) (def : type_decl) :
               let field_names =
                 FieldId.mapi
                   (fun fid (field : field) ->
-                    (fid, ctx.fmt.field_name def.name fid field.field_name))
+                    ( fid,
+                      ctx_compute_field_name ctx def.llbc_name fid
+                        field.field_name ))
                   fields
               in
-              let cons_name = ctx.fmt.struct_constructor def.name in
+              let cons_name =
+                ctx_compute_struct_constructor ctx def.llbc_name
+              in
               (field_names, cons_name)
           | Some { body_info = Some (Struct (cons_name, field_names)); _ } ->
               let field_names =
@@ -1487,11 +723,11 @@ let extract_type_decl_register_names (ctx : extraction_ctx) (def : type_decl) :
         let ctx =
           List.fold_left
             (fun ctx (fid, name) ->
-              ctx_add (FieldId (AdtId def.def_id, fid)) name ctx)
+              ctx_add (FieldId (TAdtId def.def_id, fid)) name ctx)
             ctx field_names
         in
         (* Add the constructor name *)
-        ctx_add (StructId (AdtId def.def_id)) cons_name ctx
+        ctx_add (StructId (TAdtId def.def_id)) cons_name ctx
     | Enum variants ->
         let variant_names =
           match info with
@@ -1499,12 +735,13 @@ let extract_type_decl_register_names (ctx : extraction_ctx) (def : type_decl) :
               VariantId.mapi
                 (fun variant_id (variant : variant) ->
                   let name =
-                    ctx.fmt.variant_name def.name variant.variant_name
+                    ctx_compute_variant_name ctx def.llbc_name
+                      variant.variant_name
                   in
                   (* Add the type name prefix for Lean *)
                   let name =
                     if !Config.backend = Lean then
-                      let type_name = ctx.fmt.type_name def.name in
+                      let type_name = ctx_compute_type_name ctx def.llbc_name in
                       type_name ^ "." ^ name
                     else name
                   in
@@ -1527,7 +764,7 @@ let extract_type_decl_register_names (ctx : extraction_ctx) (def : type_decl) :
         in
         List.fold_left
           (fun ctx (vid, vname) ->
-            ctx_add (VariantId (AdtId def.def_id, vid)) vname ctx)
+            ctx_add (VariantId (TAdtId def.def_id, vid)) vname ctx)
           ctx variant_names
     | Opaque ->
         (* Nothing to do *)
@@ -1566,8 +803,7 @@ let extract_type_decl_variant (ctx : extraction_ctx) (fmt : F.formatter)
           | Some field_name ->
               let var_id = VarId.of_int (FieldId.to_int fid) in
               let field_name =
-                ctx.fmt.var_basename ctx.names_maps.names_map.names_set
-                  (Some field_name) f.field_ty
+                ctx_compute_var_basename ctx (Some field_name) f.field_ty
               in
               let ctx, field_name = ctx_add_var field_name var_id ctx in
               F.pp_print_string fmt (field_name ^ " :");
@@ -1648,7 +884,7 @@ let extract_type_decl_enum_body (ctx : extraction_ctx) (fmt : F.formatter)
   let print_variant _variant_id (v : variant) =
     (* We don't lookup the name, because it may have a prefix for the type
        id (in the case of Lean) *)
-    let cons_name = ctx.fmt.variant_name def.name v.variant_name in
+    let cons_name = ctx_compute_variant_name ctx def.llbc_name v.variant_name in
     let fields = v.fields in
     extract_type_decl_variant ctx fmt type_decl_group def_name type_params
       cg_params cons_name fields
@@ -1730,7 +966,7 @@ let extract_type_decl_struct_body (ctx : extraction_ctx) (fmt : F.formatter)
       (* If Coq: print the constructor name *)
       (* TODO: remove superfluous test not is_rec below *)
       if !backend = Coq && not is_rec then (
-        F.pp_print_string fmt (ctx_get_struct (AdtId def.def_id) ctx);
+        F.pp_print_string fmt (ctx_get_struct (TAdtId def.def_id) ctx);
         F.pp_print_string fmt " ");
       (match !backend with
       | Lean -> ()
@@ -1744,7 +980,7 @@ let extract_type_decl_struct_body (ctx : extraction_ctx) (fmt : F.formatter)
       | Lean -> F.pp_open_vbox fmt 0);
       (* Print the fields *)
       let print_field (field_id : FieldId.id) (f : field) : unit =
-        let field_name = ctx_get_field (AdtId def.def_id) field_id ctx in
+        let field_name = ctx_get_field (TAdtId def.def_id) field_id ctx in
         (* Open a box for the field *)
         F.pp_open_box fmt ctx.indent_incr;
         F.pp_print_string fmt field_name;
@@ -1779,7 +1015,7 @@ let extract_type_decl_struct_body (ctx : extraction_ctx) (fmt : F.formatter)
          i.e., instead of generating `inductive Foo := | MkFoo ...` like in Coq
          we generate `inductive Foo := | mk ... *)
       let cons_name =
-        if !backend = Lean then "mk" else ctx_get_struct (AdtId def.def_id) ctx
+        if !backend = Lean then "mk" else ctx_get_struct (TAdtId def.def_id) ctx
       in
       let def_name = ctx_get_local_type def.def_id ctx in
       extract_type_decl_variant ctx fmt type_decl_group def_name type_params
@@ -1809,6 +1045,18 @@ let extract_comment (fmt : F.formatter) (sl : string list) : unit =
   F.pp_print_string fmt rd;
   F.pp_close_box fmt ()
 
+let extract_comment_with_span (fmt : F.formatter) (sl : string list)
+    (span : Meta.span) : unit =
+  let file = match span.file with Virtual s | Local s -> s in
+  let loc_to_string (l : Meta.loc) : string =
+    string_of_int l.line ^ ":" ^ string_of_int l.col
+  in
+  let span =
+    "Source: '" ^ file ^ "', lines " ^ loc_to_string span.beg_loc ^ "-"
+    ^ loc_to_string span.end_loc
+  in
+  extract_comment fmt (sl @ [ span ])
+
 let extract_trait_clause_type (ctx : extraction_ctx) (fmt : F.formatter)
     (no_params_tys : TypeDeclId.Set.t) (clause : trait_clause) : unit =
   let trait_name = ctx_get_trait_decl clause.trait_id ctx in
@@ -2024,13 +1272,15 @@ let extract_type_decl_gen (ctx : extraction_ctx) (fmt : F.formatter)
   (* Add the type and const generic params - note that we need those bindings only for the
    * body translation (they are not top-level) *)
   let ctx_body, type_params, cg_params, trait_clauses =
-    ctx_add_generic_params def.generics ctx
+    ctx_add_generic_params def.llbc_name def.llbc_generics def.generics ctx
   in
   (* Add a break before *)
   if !backend <> HOL4 || not (decl_is_first_from_group kind) then
     F.pp_print_break fmt 0 0;
   (* Print a comment to link the extracted type to its original rust definition *)
-  extract_comment fmt [ "[" ^ Print.name_to_string def.name ^ "]" ];
+  extract_comment_with_span fmt
+    [ "[" ^ name_to_string ctx def.llbc_name ^ "]" ]
+    def.meta.span;
   F.pp_print_break fmt 0 0;
   (* Open a box for the definition, so that whenever possible it gets printed on
    * one line. Note however that in the case of Lean line breaks are important
@@ -2041,7 +1291,7 @@ let extract_type_decl_gen (ctx : extraction_ctx) (fmt : F.formatter)
   (* Open a box for "type TYPE_NAME (TYPE_PARAMS CONST_GEN_PARAMS) =" *)
   F.pp_open_hovbox fmt ctx.indent_incr;
   (* > "type TYPE_NAME" *)
-  let qualif = ctx.fmt.type_decl_kind_to_qualif kind type_kind in
+  let qualif = type_decl_kind_to_qualif kind type_kind in
   (match qualif with
   | Some qualif -> F.pp_print_string fmt (qualif ^ " " ^ def_name)
   | None -> F.pp_print_string fmt def_name);
@@ -2223,7 +1473,7 @@ let extract_type_decl_coq_arguments (ctx : extraction_ctx) (fmt : F.formatter)
     match decl.kind with
     | Opaque -> ()
     | Struct fields ->
-        let adt_id = AdtId decl.def_id in
+        let adt_id = TAdtId decl.def_id in
         (* Generate the instruction for the record constructor *)
         let cons_name = ctx_get_struct adt_id ctx in
         extract_coq_arguments_instruction ctx fmt cons_name num_params;
@@ -2241,7 +1491,7 @@ let extract_type_decl_coq_arguments (ctx : extraction_ctx) (fmt : F.formatter)
         (* Generate the instructions *)
         VariantId.iteri
           (fun vid (_ : variant) ->
-            let cons_name = ctx_get_variant (AdtId decl.def_id) vid ctx in
+            let cons_name = ctx_get_variant (TAdtId decl.def_id) vid ctx in
             extract_coq_arguments_instruction ctx fmt cons_name num_params)
           variants;
         (* Add breaks to insert new lines between definitions *)
@@ -2265,12 +1515,13 @@ let extract_type_decl_record_field_projectors (ctx : extraction_ctx)
       if is_rec then
         (* Add the type params *)
         let ctx, type_params, cg_params, trait_clauses =
-          ctx_add_generic_params decl.generics ctx
+          ctx_add_generic_params decl.llbc_name decl.llbc_generics decl.generics
+            ctx
         in
         let ctx, record_var = ctx_add_var "x" (VarId.of_int 0) ctx in
         let ctx, field_var = ctx_add_var "x" (VarId.of_int 1) ctx in
         let def_name = ctx_get_local_type decl.def_id ctx in
-        let cons_name = ctx_get_struct (AdtId decl.def_id) ctx in
+        let cons_name = ctx_get_struct (TAdtId decl.def_id) ctx in
         let extract_field_proj (field_id : FieldId.id) (_ : field) : unit =
           F.pp_print_space fmt ();
           (* Outer box for the projector definition *)
@@ -2281,7 +1532,7 @@ let extract_type_decl_record_field_projectors (ctx : extraction_ctx)
           F.pp_open_hovbox fmt ctx.indent_incr;
           F.pp_print_string fmt "Definition";
           F.pp_print_space fmt ();
-          let field_name = ctx_get_field (AdtId decl.def_id) field_id ctx in
+          let field_name = ctx_get_field (TAdtId decl.def_id) field_id ctx in
           F.pp_print_string fmt field_name;
           (* Print the generics *)
           let as_implicits = true in
@@ -2364,7 +1615,7 @@ let extract_type_decl_record_field_projectors (ctx : extraction_ctx)
           let ctx, record_var = ctx_add_var "x" (VarId.of_int 0) ctx in
           F.pp_print_string fmt "Notation";
           F.pp_print_space fmt ();
-          let field_name = ctx_get_field (AdtId decl.def_id) field_id ctx in
+          let field_name = ctx_get_field (TAdtId decl.def_id) field_id ctx in
           F.pp_print_string fmt ("\"" ^ record_var ^ " .(" ^ field_name ^ ")\"");
           F.pp_print_space fmt ();
           F.pp_print_string fmt ":=";
@@ -2421,7 +1672,7 @@ let extract_state_type (fmt : F.formatter) (ctx : extraction_ctx)
    * one line *)
   F.pp_open_hvbox fmt 0;
   (* Retrieve the name *)
-  let state_name = ctx_get_assumed_type State ctx in
+  let state_name = ctx_get_assumed_type TState ctx in
   (* The syntax for Lean and Coq is almost identical. *)
   let print_axiom () =
     let axiom =
diff --git a/compiler/FunsAnalysis.ml b/compiler/FunsAnalysis.ml
index e17ea16f..9ae6ce86 100644
--- a/compiler/FunsAnalysis.ml
+++ b/compiler/FunsAnalysis.ml
@@ -8,7 +8,7 @@
  *)
 
 open LlbcAst
-module EU = ExpressionsUtils
+open ExpressionsUtils
 
 (** Various information about a function.
 
@@ -58,6 +58,13 @@ let analyze_module (m : crate) (funs_map : fun_decl FunDeclId.Map.t)
     let can_diverge = ref false in
     let is_rec = ref false in
     let group_has_builtin_info = ref false in
+    let name_matcher_ctx : Charon.NameMatcher.ctx =
+      {
+        type_decls = m.type_decls;
+        global_decls = m.global_decls;
+        trait_decls = m.trait_decls;
+      }
+    in
 
     (* We have some specialized knowledge of some library functions; we don't
        have any more custom treatment than this, and these functions can be modeled
@@ -65,8 +72,7 @@ let analyze_module (m : crate) (funs_map : fun_decl FunDeclId.Map.t)
        way. *)
     let get_builtin_info (f : fun_decl) : ExtractBuiltin.effect_info option =
       let open ExtractBuiltin in
-      let name = name_to_simple_name f.name in
-      SimpleNameMap.find_opt name builtin_fun_effects_map
+      NameMatcherMap.find_opt name_matcher_ctx f.name builtin_fun_effects_map
     in
 
     (* JP: Why not use a reduce visitor here with a tuple of the values to be
@@ -85,13 +91,13 @@ let analyze_module (m : crate) (funs_map : fun_decl FunDeclId.Map.t)
           method! visit_rvalue _env rv =
             match rv with
             | Use _ | RvRef _ | Global _ | Discriminant _ | Aggregate _ -> ()
-            | UnaryOp (uop, _) -> can_fail := EU.unop_can_fail uop || !can_fail
+            | UnaryOp (uop, _) -> can_fail := unop_can_fail uop || !can_fail
             | BinaryOp (bop, _, _) ->
-                can_fail := EU.binop_can_fail bop || !can_fail
+                can_fail := binop_can_fail bop || !can_fail
 
           method! visit_Call env call =
             (match call.func.func with
-            | FunId (Regular id) ->
+            | FunId (FRegular id) ->
                 if FunDeclId.Set.mem id fun_ids then (
                   can_diverge := true;
                   is_rec := true)
@@ -100,7 +106,7 @@ let analyze_module (m : crate) (funs_map : fun_decl FunDeclId.Map.t)
                   self#may_fail info.can_fail;
                   stateful := !stateful || info.stateful;
                   can_diverge := !can_diverge || info.can_diverge
-            | FunId (Assumed id) ->
+            | FunId (FAssumed id) ->
                 (* None of the assumed functions can diverge nor are considered stateful *)
                 can_fail := !can_fail || Assumed.assumed_fun_can_fail id
             | TraitMethod _ ->
@@ -164,7 +170,7 @@ let analyze_module (m : crate) (funs_map : fun_decl FunDeclId.Map.t)
 
   let analyze_fun_decl_group (d : fun_declaration_group) : unit =
     (* Retrieve the function declarations *)
-    let funs = match d with NonRec id -> [ id ] | Rec ids -> ids in
+    let funs = match d with NonRecGroup id -> [ id ] | RecGroup ids -> ids in
     let funs = List.map (fun id -> FunDeclId.Map.find id funs_map) funs in
     let fun_ids = List.map (fun (d : fun_decl) -> d.def_id) funs in
     let fun_ids = FunDeclId.Set.of_list fun_ids in
@@ -175,15 +181,15 @@ let analyze_module (m : crate) (funs_map : fun_decl FunDeclId.Map.t)
   let rec analyze_decl_groups (decls : declaration_group list) : unit =
     match decls with
     | [] -> ()
-    | (Type _ | TraitDecl _ | TraitImpl _) :: decls' ->
+    | (TypeGroup _ | TraitDeclGroup _ | TraitImplGroup _) :: decls' ->
         analyze_decl_groups decls'
-    | Fun decl :: decls' ->
+    | FunGroup decl :: decls' ->
         analyze_fun_decl_group decl;
         analyze_decl_groups decls'
-    | Global id :: decls' ->
+    | GlobalGroup id :: decls' ->
         (* Analyze a global by analyzing its body function *)
         let global = GlobalDeclId.Map.find id globals_map in
-        analyze_fun_decl_group (NonRec global.body_id);
+        analyze_fun_decl_group (NonRecGroup global.body);
         analyze_decl_groups decls'
   in
 
diff --git a/compiler/Interpreter.ml b/compiler/Interpreter.ml
index 24ff4808..c2e47da9 100644
--- a/compiler/Interpreter.ml
+++ b/compiler/Interpreter.ml
@@ -4,19 +4,22 @@ open InterpreterProjectors
 open InterpreterBorrows
 open InterpreterStatements
 open LlbcAstUtils
-module L = Logging
-module T = Types
-module A = LlbcAst
+open Types
+open TypesUtils
+open Values
+open LlbcAst
+open Contexts
+open SynthesizeSymbolic
 module SA = SymbolicAst
 
 (** The local logger *)
-let log = L.interpreter_log
+let log = Logging.interpreter_log
 
-let compute_contexts (m : A.crate) : C.decls_ctx =
+let compute_contexts (m : crate) : decls_ctx =
   let type_decls_list, _, _, _, _ = split_declarations m.declarations in
-  let type_decls = m.types in
-  let fun_decls = m.functions in
-  let global_decls = m.globals in
+  let type_decls = m.type_decls in
+  let fun_decls = m.fun_decls in
+  let global_decls = m.global_decls in
   let trait_decls = m.trait_decls in
   let trait_impls = m.trait_impls in
   let type_decls_groups, _, _, _, _ =
@@ -25,15 +28,19 @@ let compute_contexts (m : A.crate) : C.decls_ctx =
   let type_infos =
     TypesAnalysis.analyze_type_declarations type_decls type_decls_list
   in
-  let type_ctx = { C.type_decls_groups; type_decls; type_infos } in
+  let type_ctx = { type_decls_groups; type_decls; type_infos } in
   let fun_infos =
     FunsAnalysis.analyze_module m fun_decls global_decls !Config.use_state
   in
-  let fun_ctx = { C.fun_decls; fun_infos } in
-  let global_ctx = { C.global_decls } in
-  let trait_decls_ctx = { C.trait_decls } in
-  let trait_impls_ctx = { C.trait_impls } in
-  { C.type_ctx; fun_ctx; global_ctx; trait_decls_ctx; trait_impls_ctx }
+  let regions_hierarchies =
+    RegionsHierarchy.compute_regions_hierarchies type_decls fun_decls
+      global_decls trait_decls trait_impls
+  in
+  let fun_ctx = { fun_decls; fun_infos; regions_hierarchies } in
+  let global_ctx = { global_decls } in
+  let trait_decls_ctx = { trait_decls } in
+  let trait_impls_ctx = { trait_impls } in
+  { type_ctx; fun_ctx; global_ctx; trait_decls_ctx; trait_impls_ctx }
 
 (** Small helper.
 
@@ -41,15 +48,14 @@ let compute_contexts (m : A.crate) : C.decls_ctx =
     to compute a normalization map (for the associated types) and that we added
     it in the context.
  *)
-let normalize_inst_fun_sig (ctx : C.eval_ctx) (sg : A.inst_fun_sig) :
-    A.inst_fun_sig =
-  let { A.regions_hierarchy = _; trait_type_constraints = _; inputs; output } =
+let normalize_inst_fun_sig (ctx : eval_ctx) (sg : inst_fun_sig) : inst_fun_sig =
+  let { regions_hierarchy = _; trait_type_constraints = _; inputs; output } =
     sg
   in
-  let norm = AssociatedTypes.ctx_normalize_rty ctx in
+  let norm = AssociatedTypes.ctx_normalize_ty ctx in
   let inputs = List.map norm inputs in
   let output = norm output in
-  { sg with A.inputs; output }
+  { sg with inputs; output }
 
 (** Instantiate a function signature for a symbolic execution.
 
@@ -61,27 +67,28 @@ let normalize_inst_fun_sig (ctx : C.eval_ctx) (sg : A.inst_fun_sig) :
     clauses (we are not considering a function call, so we don't need to
     normalize because a trait clause was instantiated with a specific trait ref).
  *)
-let symbolic_instantiate_fun_sig (ctx : C.eval_ctx) (sg : A.fun_sig)
-    (kind : A.fun_kind) : C.eval_ctx * A.inst_fun_sig =
+let symbolic_instantiate_fun_sig (ctx : eval_ctx) (sg : fun_sig)
+    (regions_hierarchy : region_groups) (kind : fun_kind) :
+    eval_ctx * inst_fun_sig =
   let tr_self =
     match kind with
-    | RegularKind | TraitMethodImpl _ -> T.UnknownTrait __FUNCTION__
-    | TraitMethodDecl _ | TraitMethodProvided _ -> T.Self
+    | RegularKind | TraitMethodImpl _ -> UnknownTrait __FUNCTION__
+    | TraitMethodDecl _ | TraitMethodProvided _ -> Self
   in
   let generics =
-    let { T.regions; types; const_generics; trait_clauses } = sg.generics in
-    let regions = List.map (fun _ -> T.Erased) regions in
-    let types = List.map (fun (v : T.type_var) -> T.TypeVar v.T.index) types in
+    let { regions; types; const_generics; trait_clauses } = sg.generics in
+    let regions = List.map (fun _ -> RErased) regions in
+    let types = List.map (fun (v : type_var) -> TVar v.index) types in
     let const_generics =
-      List.map
-        (fun (v : T.const_generic_var) -> T.ConstGenericVar v.T.index)
-        const_generics
+      List.map (fun (v : const_generic_var) -> CgVar v.index) const_generics
     in
     (* Annoying that we have to generate this substitution here *)
     let r_subst _ = raise (Failure "Unexpected region") in
-    let ty_subst = Subst.make_type_subst_from_vars sg.generics.types types in
+    let ty_subst =
+      Substitute.make_type_subst_from_vars sg.generics.types types
+    in
     let cg_subst =
-      Subst.make_const_generic_subst_from_vars sg.generics.const_generics
+      Substitute.make_const_generic_subst_from_vars sg.generics.const_generics
         const_generics
     in
     (* TODO: some clauses may use the types of other clauses, so we may have to
@@ -110,42 +117,39 @@ let symbolic_instantiate_fun_sig (ctx : C.eval_ctx) (sg : A.fun_sig)
        ]}
     *)
     (* We will need to update the trait refs map while we perform the instantiations *)
-    let mk_tr_subst
-        (tr_map : T.erased_region T.trait_instance_id T.TraitClauseId.Map.t)
-        clause_id : T.erased_region T.trait_instance_id =
-      match T.TraitClauseId.Map.find_opt clause_id tr_map with
+    let mk_tr_subst (tr_map : trait_instance_id TraitClauseId.Map.t) clause_id :
+        trait_instance_id =
+      match TraitClauseId.Map.find_opt clause_id tr_map with
       | Some tr -> tr
       | None -> raise (Failure "Local trait clause not found")
     in
     let mk_subst tr_map =
       let tr_subst = mk_tr_subst tr_map in
-      { Subst.r_subst; ty_subst; cg_subst; tr_subst; tr_self }
+      { Substitute.r_subst; ty_subst; cg_subst; tr_subst; tr_self }
     in
     let _, trait_refs =
       List.fold_left_map
-        (fun tr_map (c : T.trait_clause) ->
+        (fun tr_map (c : trait_clause) ->
           let subst = mk_subst tr_map in
-          let { T.trait_id = trait_decl_id; generics; _ } = c in
-          let generics = Subst.generic_args_substitute subst generics in
-          let trait_decl_ref = { T.trait_decl_id; decl_generics = generics } in
+          let { trait_id = trait_decl_id; clause_generics; _ } = c in
+          let generics =
+            Substitute.generic_args_substitute subst clause_generics
+          in
+          let trait_decl_ref = { trait_decl_id; decl_generics = generics } in
           (* Note that because we directly refer to the clause, we give it
              empty generics *)
-          let trait_id = T.Clause c.clause_id in
+          let trait_id = Clause c.clause_id in
           let trait_ref =
-            {
-              T.trait_id;
-              generics = TypesUtils.mk_empty_generic_args;
-              trait_decl_ref;
-            }
+            { trait_id; generics = empty_generic_args; trait_decl_ref }
           in
           (* Update the traits map *)
-          let tr_map = T.TraitClauseId.Map.add c.T.clause_id trait_id tr_map in
+          let tr_map = TraitClauseId.Map.add c.clause_id trait_id tr_map in
           (tr_map, trait_ref))
-        T.TraitClauseId.Map.empty trait_clauses
+        TraitClauseId.Map.empty trait_clauses
     in
-    { T.regions; types; const_generics; trait_refs }
+    { regions; types; const_generics; trait_refs }
   in
-  let inst_sg = instantiate_fun_sig ctx generics tr_self sg in
+  let inst_sg = instantiate_fun_sig ctx generics tr_self sg regions_hierarchy in
   (* Compute the normalization maps *)
   let ctx =
     AssociatedTypes.ctx_add_norm_trait_types_from_preds ctx
@@ -169,8 +173,8 @@ let symbolic_instantiate_fun_sig (ctx : C.eval_ctx) (sg : A.fun_sig)
     - the list of symbolic values introduced for the input values
     - the instantiated function signature
  *)
-let initialize_symbolic_context_for_fun (ctx : C.decls_ctx) (fdef : A.fun_decl)
-    : C.eval_ctx * V.symbolic_value list * A.inst_fun_sig =
+let initialize_symbolic_context_for_fun (ctx : decls_ctx) (fdef : fun_decl) :
+    eval_ctx * symbolic_value list * inst_fun_sig =
   (* The abstractions are not initialized the same way as for function
    * calls: they contain *loan* projectors, because they "provide" us
    * with the input values (which behave as if they had been returned
@@ -184,8 +188,11 @@ let initialize_symbolic_context_for_fun (ctx : C.decls_ctx) (fdef : A.fun_decl)
    * *)
   let sg = fdef.signature in
   (* Create the context *)
+  let regions_hierarchy =
+    FunIdMap.find (FRegular fdef.def_id) ctx.fun_ctx.regions_hierarchies
+  in
   let region_groups =
-    List.map (fun (g : T.region_var_group) -> g.id) sg.regions_hierarchy
+    List.map (fun (g : region_group) -> g.id) regions_hierarchy
   in
   let ctx =
     initialize_eval_context ctx region_groups sg.generics.types
@@ -195,17 +202,17 @@ let initialize_symbolic_context_for_fun (ctx : C.decls_ctx) (fdef : A.fun_decl)
      at the same time the normalization map for the associated types.
   *)
   let ctx, inst_sg =
-    symbolic_instantiate_fun_sig ctx fdef.signature fdef.kind
+    symbolic_instantiate_fun_sig ctx fdef.signature regions_hierarchy fdef.kind
   in
   (* Create fresh symbolic values for the inputs *)
   let input_svs =
-    List.map (fun ty -> mk_fresh_symbolic_value V.SynthInput ty) inst_sg.inputs
+    List.map (fun ty -> mk_fresh_symbolic_value SynthInput ty) inst_sg.inputs
   in
   (* Initialize the abstractions as empty (i.e., with no avalues) abstractions *)
-  let call_id = C.fresh_fun_call_id () in
-  assert (call_id = V.FunCallId.zero);
-  let compute_abs_avalues (abs : V.abs) (ctx : C.eval_ctx) :
-      C.eval_ctx * V.typed_avalue list =
+  let call_id = fresh_fun_call_id () in
+  assert (call_id = FunCallId.zero);
+  let compute_abs_avalues (abs : abs) (ctx : eval_ctx) :
+      eval_ctx * typed_avalue list =
     (* Project over the values - we use *loan* projectors, as explained above *)
     let avalues =
       List.map (mk_aproj_loans_value_from_symbolic_value abs.regions) input_svs
@@ -215,8 +222,8 @@ let initialize_symbolic_context_for_fun (ctx : C.decls_ctx) (fdef : A.fun_decl)
   let region_can_end _ = false in
   let ctx =
     create_push_abstractions_from_abs_region_groups
-      (fun rg_id -> V.SynthInput rg_id)
-      inst_sg.A.regions_hierarchy region_can_end compute_abs_avalues ctx
+      (fun rg_id -> SynthInput rg_id)
+      inst_sg.regions_hierarchy region_can_end compute_abs_avalues ctx
   in
   (* Split the variables between return var, inputs and remaining locals *)
   let body = Option.get fdef.body in
@@ -225,12 +232,12 @@ let initialize_symbolic_context_for_fun (ctx : C.decls_ctx) (fdef : A.fun_decl)
     Collections.List.split_at (List.tl body.locals) body.arg_count
   in
   (* Push the return variable (initialized with ⊥) *)
-  let ctx = C.ctx_push_uninitialized_var ctx ret_var in
+  let ctx = ctx_push_uninitialized_var ctx ret_var in
   (* Push the input variables (initialized with symbolic values) *)
   let input_values = List.map mk_typed_value_from_symbolic_value input_svs in
-  let ctx = C.ctx_push_vars ctx (List.combine input_vars input_values) in
+  let ctx = ctx_push_vars ctx (List.combine input_vars input_values) in
   (* Push the remaining local variables (initialized with ⊥) *)
-  let ctx = C.ctx_push_uninitialized_vars ctx local_vars in
+  let ctx = ctx_push_uninitialized_vars ctx local_vars in
   (* Return *)
   (ctx, input_svs, inst_sg)
 
@@ -246,20 +253,19 @@ let initialize_symbolic_context_for_fun (ctx : C.decls_ctx) (fdef : A.fun_decl)
 
     [inside_loop]: [true] if we are *inside* a loop (result [EndContinue]).
 *)
-let evaluate_function_symbolic_synthesize_backward_from_return
-    (config : C.config) (fdef : A.fun_decl) (inst_sg : A.inst_fun_sig)
-    (back_id : T.RegionGroupId.id) (loop_id : V.LoopId.id option)
-    (is_regular_return : bool) (inside_loop : bool) (ctx : C.eval_ctx) :
-    SA.expression option =
+let evaluate_function_symbolic_synthesize_backward_from_return (config : config)
+    (fdef : fun_decl) (inst_sg : inst_fun_sig) (back_id : RegionGroupId.id)
+    (loop_id : LoopId.id option) (is_regular_return : bool) (inside_loop : bool)
+    (ctx : eval_ctx) : SA.expression option =
   log#ldebug
     (lazy
       ("evaluate_function_symbolic_synthesize_backward_from_return:"
      ^ "\n- fname: "
-      ^ Print.fun_name_to_string fdef.name
+      ^ Print.EvalCtx.name_to_string ctx fdef.name
       ^ "\n- back_id: "
-      ^ T.RegionGroupId.to_string back_id
+      ^ RegionGroupId.to_string back_id
       ^ "\n- loop_id: "
-      ^ Print.option_to_string V.LoopId.to_string loop_id
+      ^ Print.option_to_string LoopId.to_string loop_id
       ^ "\n- is_regular_return: "
       ^ Print.bool_to_string is_regular_return
       ^ "\n- inside_loop: "
@@ -270,9 +276,11 @@ let evaluate_function_symbolic_synthesize_backward_from_return
    * the return type. Note that it is important to re-generate
    * an instantiation of the signature, so that we use fresh
    * region ids for the return abstractions. *)
-  let sg = fdef.signature in
+  let regions_hierarchy =
+    FunIdMap.find (FRegular fdef.def_id) ctx.fun_context.regions_hierarchies
+  in
   let _, ret_inst_sg =
-    symbolic_instantiate_fun_sig ctx fdef.signature fdef.kind
+    symbolic_instantiate_fun_sig ctx fdef.signature regions_hierarchy fdef.kind
   in
   let ret_rty = ret_inst_sg.output in
   (* Move the return value out of the return variable *)
@@ -283,11 +291,11 @@ let evaluate_function_symbolic_synthesize_backward_from_return
    * will end - this will allow us to, first, mark the other return
    * regions as non-endable, and, second, end those parent regions in
    * proper order. *)
-  let parent_rgs = list_ancestor_region_groups sg back_id in
+  let parent_rgs = list_ancestor_region_groups regions_hierarchy back_id in
   let parent_input_abs_ids =
-    T.RegionGroupId.mapi
+    RegionGroupId.mapi
       (fun rg_id rg ->
-        if T.RegionGroupId.Set.mem rg_id parent_rgs then Some rg.T.id else None)
+        if RegionGroupId.Set.mem rg_id parent_rgs then Some rg.id else None)
       inst_sg.regions_hierarchy
   in
   let parent_input_abs_ids =
@@ -296,12 +304,12 @@ let evaluate_function_symbolic_synthesize_backward_from_return
 
   (* Insert the return value in the return abstractions (by applying
    * borrow projections) *)
-  let cf_consume_ret (ret_value : V.typed_value option) ctx =
+  let cf_consume_ret (ret_value : typed_value option) ctx =
     let ctx =
       if is_regular_return then (
         let ret_value = Option.get ret_value in
-        let compute_abs_avalues (abs : V.abs) (ctx : C.eval_ctx) :
-            C.eval_ctx * V.typed_avalue list =
+        let compute_abs_avalues (abs : abs) (ctx : eval_ctx) :
+            eval_ctx * typed_avalue list =
           let ctx, avalue =
             apply_proj_borrows_on_input_value config ctx abs.regions
               abs.ancestors_regions ret_value ret_rty
@@ -315,18 +323,15 @@ let evaluate_function_symbolic_synthesize_backward_from_return
          * that this is important for soundness: this is part of the borrow checking).
          * Also see the documentation of the [can_end] field of [abs] for more
          * information. *)
-        let parent_and_current_rgs =
-          T.RegionGroupId.Set.add back_id parent_rgs
-        in
+        let parent_and_current_rgs = RegionGroupId.Set.add back_id parent_rgs in
         let region_can_end rid =
-          T.RegionGroupId.Set.mem rid parent_and_current_rgs
+          RegionGroupId.Set.mem rid parent_and_current_rgs
         in
         assert (region_can_end back_id);
         let ctx =
           create_push_abstractions_from_abs_region_groups
-            (fun rg_id -> V.SynthRet rg_id)
-            ret_inst_sg.A.regions_hierarchy region_can_end compute_abs_avalues
-            ctx
+            (fun rg_id -> SynthRet rg_id)
+            ret_inst_sg.regions_hierarchy region_can_end compute_abs_avalues ctx
         in
         ctx)
       else ctx
@@ -347,16 +352,16 @@ let evaluate_function_symbolic_synthesize_backward_from_return
      *)
     let current_abs_id, end_fun_synth_input =
       let fun_abs_id =
-        (T.RegionGroupId.nth inst_sg.regions_hierarchy back_id).id
+        (RegionGroupId.nth inst_sg.regions_hierarchy back_id).id
       in
       if not inside_loop then (fun_abs_id, true)
       else
-        let pred (abs : V.abs) =
+        let pred (abs : abs) =
           match abs.kind with
-          | V.Loop (_, rg_id', kind) ->
+          | Loop (_, rg_id', kind) ->
               let rg_id' = Option.get rg_id' in
               let is_ret =
-                match kind with V.LoopSynthInput -> true | V.LoopCall -> false
+                match kind with LoopSynthInput -> true | LoopCall -> false
               in
               rg_id' = back_id && is_ret
           | _ -> false
@@ -378,24 +383,24 @@ let evaluate_function_symbolic_synthesize_backward_from_return
              }
            ]}
         *)
-        let abs = Option.get (C.ctx_find_abs ctx pred) in
+        let abs = Option.get (ctx_find_abs ctx pred) in
         (abs.abs_id, false)
     in
     log#ldebug
       (lazy
         ("evaluate_function_symbolic_synthesize_backward_from_return: ending \
           input abstraction: "
-        ^ V.AbstractionId.to_string current_abs_id));
+        ^ AbstractionId.to_string current_abs_id));
 
     (* Set the proper abstractions as endable *)
     let ctx =
       let visit_loop_abs =
         object
-          inherit [_] C.map_eval_ctx
+          inherit [_] map_eval_ctx
 
           method! visit_abs _ abs =
             match abs.kind with
-            | V.Loop (loop_id', rg_id', V.LoopSynthInput) ->
+            | Loop (loop_id', rg_id', LoopSynthInput) ->
                 (* We only allow to end the loop synth input abs for the region
                    group [rg_id] *)
                 assert (
@@ -406,11 +411,11 @@ let evaluate_function_symbolic_synthesize_backward_from_return
                 if rg_id' = back_id && inside_loop then
                   { abs with can_end = true }
                 else abs
-            | V.Loop (loop_id', _, V.LoopCall) ->
+            | Loop (loop_id', _, LoopCall) ->
                 (* We can end all the loop call abstractions *)
                 assert (loop_id = Some loop_id');
                 { abs with can_end = true }
-            | V.SynthInput rg_id' ->
+            | SynthInput rg_id' ->
                 if rg_id' = back_id && end_fun_synth_input then
                   { abs with can_end = true }
                 else abs
@@ -447,18 +452,26 @@ let evaluate_function_symbolic_synthesize_backward_from_return
       for the synthesis)
     - the symbolic AST generated by the symbolic execution
  *)
-let evaluate_function_symbolic (synthesize : bool) (ctx : C.decls_ctx)
-    (fdef : A.fun_decl) : V.symbolic_value list * SA.expression option =
+let evaluate_function_symbolic (synthesize : bool) (ctx : decls_ctx)
+    (fdef : fun_decl) : symbolic_value list * SA.expression option =
   (* Debug *)
-  let name_to_string () = Print.fun_name_to_string fdef.A.name in
+  let name_to_string () =
+    Print.Types.name_to_string
+      (Print.Contexts.decls_ctx_to_fmt_env ctx)
+      fdef.name
+  in
   log#ldebug (lazy ("evaluate_function_symbolic: " ^ name_to_string ()));
 
   (* Create the evaluation context *)
   let ctx, input_svs, inst_sg = initialize_symbolic_context_for_fun ctx fdef in
 
+  let regions_hierarchy =
+    FunIdMap.find (FRegular fdef.def_id) ctx.fun_context.regions_hierarchies
+  in
+
   (* Create the continuation to finish the evaluation *)
-  let config = C.mk_config C.SymbolicMode in
-  let cf_finish res ctx =
+  let config = mk_config SymbolicMode in
+  let cf_finish (res : statement_eval_res) (ctx : eval_ctx) =
     let ctx0 = ctx in
     log#ldebug
       (lazy
@@ -510,13 +523,13 @@ let evaluate_function_symbolic (synthesize : bool) (ctx : C.decls_ctx)
                  fdef inst_sg back_id loop_id is_regular_return inside_loop ctx)
           in
           let back_el =
-            T.RegionGroupId.mapi
+            RegionGroupId.mapi
               (fun gid _ -> (gid, finish_back_eval gid))
-              fdef.signature.regions_hierarchy
+              regions_hierarchy
           in
-          let back_el = T.RegionGroupId.Map.of_list back_el in
+          let back_el = RegionGroupId.Map.of_list back_el in
           (* Put everything together *)
-          S.synthesize_forward_end ctx0 None fwd_e back_el
+          synthesize_forward_end ctx0 None fwd_e back_el
         else None
     | EndEnterLoop (loop_id, loop_input_values)
     | EndContinue (loop_id, loop_input_values) ->
@@ -554,13 +567,13 @@ let evaluate_function_symbolic (synthesize : bool) (ctx : C.decls_ctx)
                  inside_loop ctx)
           in
           let back_el =
-            T.RegionGroupId.mapi
+            RegionGroupId.mapi
               (fun gid _ -> (gid, finish_back_eval gid))
-              fdef.signature.regions_hierarchy
+              regions_hierarchy
           in
-          let back_el = T.RegionGroupId.Map.of_list back_el in
+          let back_el = RegionGroupId.Map.of_list back_el in
           (* Put everything together *)
-          S.synthesize_forward_end ctx0 (Some loop_input_values) fwd_e back_el
+          synthesize_forward_end ctx0 (Some loop_input_values) fwd_e back_el
         else None
     | Panic ->
         (* Note that as we explore all the execution branches, one of
@@ -573,7 +586,7 @@ let evaluate_function_symbolic (synthesize : bool) (ctx : C.decls_ctx)
 
   (* Evaluate the function *)
   let symbolic =
-    eval_function_body config (Option.get fdef.A.body).body cf_finish ctx
+    eval_function_body config (Option.get fdef.body).body cf_finish ctx
   in
 
   (* Return *)
@@ -583,29 +596,33 @@ module Test = struct
   (** Test a unit function (taking no arguments) by evaluating it in an empty
       environment.
    *)
-  let test_unit_function (crate : A.crate) (decls_ctx : C.decls_ctx)
-      (fid : A.FunDeclId.id) : unit =
+  let test_unit_function (crate : crate) (decls_ctx : decls_ctx)
+      (fid : FunDeclId.id) : unit =
     (* Retrieve the function declaration *)
-    let fdef = A.FunDeclId.Map.find fid crate.functions in
+    let fdef = FunDeclId.Map.find fid crate.fun_decls in
     let body = Option.get fdef.body in
 
     (* Debug *)
     log#ldebug
-      (lazy ("test_unit_function: " ^ Print.fun_name_to_string fdef.A.name));
+      (lazy
+        ("test_unit_function: "
+        ^ Print.Types.name_to_string
+            (Print.Contexts.decls_ctx_to_fmt_env decls_ctx)
+            fdef.name));
 
     (* Sanity check - *)
-    assert (fdef.A.signature.generics = TypesUtils.mk_empty_generic_params);
-    assert (body.A.arg_count = 0);
+    assert (fdef.signature.generics = empty_generic_params);
+    assert (body.arg_count = 0);
 
     (* Create the evaluation context *)
     let ctx = initialize_eval_context decls_ctx [] [] [] in
 
     (* Insert the (uninitialized) local variables *)
-    let ctx = C.ctx_push_uninitialized_vars ctx body.A.locals in
+    let ctx = ctx_push_uninitialized_vars ctx body.locals in
 
     (* Create the continuation to check the function's result *)
-    let config = C.mk_config C.ConcreteMode in
-    let cf_check res ctx =
+    let config = mk_config ConcreteMode in
+    let cf_check (res : statement_eval_res) (ctx : eval_ctx) =
       match res with
       | Return ->
           (* Ok: drop the local variables and finish *)
@@ -615,7 +632,9 @@ module Test = struct
           raise
             (Failure
                ("Unit test failed (concrete execution) on: "
-               ^ Print.fun_name_to_string fdef.A.name))
+               ^ Print.Types.name_to_string
+                   (Print.Contexts.decls_ctx_to_fmt_env decls_ctx)
+                   fdef.name))
     in
 
     (* Evaluate the function *)
@@ -624,21 +643,21 @@ module Test = struct
 
   (** Small helper: return true if the function is a *transparent* unit function
       (no parameters, no arguments) - TODO: move *)
-  let fun_decl_is_transparent_unit (def : A.fun_decl) : bool =
+  let fun_decl_is_transparent_unit (def : fun_decl) : bool =
     Option.is_some def.body
-    && def.A.signature.generics = TypesUtils.mk_empty_generic_params
-    && def.A.signature.inputs = []
+    && def.signature.generics = empty_generic_params
+    && def.signature.inputs = []
 
   (** Test all the unit functions in a list of function definitions *)
-  let test_unit_functions (crate : A.crate) : unit =
+  let test_unit_functions (crate : crate) : unit =
     let unit_funs =
-      A.FunDeclId.Map.filter
+      FunDeclId.Map.filter
         (fun _ -> fun_decl_is_transparent_unit)
-        crate.functions
+        crate.fun_decls
     in
     let decls_ctx = compute_contexts crate in
-    let test_unit_fun _ (def : A.fun_decl) : unit =
-      test_unit_function crate decls_ctx def.A.def_id
+    let test_unit_fun _ (def : fun_decl) : unit =
+      test_unit_function crate decls_ctx def.def_id
     in
-    A.FunDeclId.Map.iter test_unit_fun unit_funs
+    FunDeclId.Map.iter test_unit_fun unit_funs
 end
diff --git a/compiler/InterpreterBorrows.ml b/compiler/InterpreterBorrows.ml
index e97795a1..8c9c0e72 100644
--- a/compiler/InterpreterBorrows.ml
+++ b/compiler/InterpreterBorrows.ml
@@ -1,9 +1,6 @@
-module T = Types
-module V = Values
-module C = Contexts
-module Subst = Substitute
-module L = Logging
-module S = SynthesizeSymbolic
+open Types
+open Values
+open Contexts
 open Cps
 open ValuesUtils
 open TypesUtils
@@ -12,11 +9,11 @@ open InterpreterBorrowsCore
 open InterpreterProjectors
 
 (** The local logger *)
-let log = L.borrows_log
+let log = Logging.borrows_log
 
 (** Auxiliary function to end borrows: lookup a borrow in the environment,
     update it (by returning an updated environment where the borrow has been
-    replaced by {!V.Bottom})) if we can end the borrow (for instance, it is not
+    replaced by {!Bottom})) if we can end the borrow (for instance, it is not
     an outer borrow...) or return the reason why we couldn't update the borrow.
 
     [end_borrow_aux] then simply performs a loop: as long as we need to end (outer)
@@ -32,18 +29,18 @@ let log = L.borrows_log
       loans. This is used to merge borrows with abstractions, to compute loop
       fixed points for instance.
 *)
-let end_borrow_get_borrow (allowed_abs : V.AbstractionId.id option)
-    (allow_inner_loans : bool) (l : V.BorrowId.id) (ctx : C.eval_ctx) :
-    ( C.eval_ctx * (V.AbstractionId.id option * g_borrow_content) option,
+let end_borrow_get_borrow (allowed_abs : AbstractionId.id option)
+    (allow_inner_loans : bool) (l : BorrowId.id) (ctx : eval_ctx) :
+    ( eval_ctx * (AbstractionId.id option * g_borrow_content) option,
       priority_borrows_or_abs )
     result =
   (* We use a reference to communicate the kind of borrow we found, if we
    * find one *)
-  let replaced_bc : (V.AbstractionId.id option * g_borrow_content) option ref =
+  let replaced_bc : (AbstractionId.id option * g_borrow_content) option ref =
     ref None
   in
-  let set_replaced_bc (abs_id : V.AbstractionId.id option)
-      (bc : g_borrow_content) =
+  let set_replaced_bc (abs_id : AbstractionId.id option) (bc : g_borrow_content)
+      =
     assert (Option.is_none !replaced_bc);
     replaced_bc := Some (abs_id, bc)
   in
@@ -52,8 +49,8 @@ let end_borrow_get_borrow (allowed_abs : V.AbstractionId.id option)
    * - if we are inside an abstraction
    * - there are inner loans
    * this exception is caught in a wrapper function *)
-  let raise_if_priority (outer : V.AbstractionId.id option * borrow_ids option)
-      (borrowed_value : V.typed_value option) =
+  let raise_if_priority (outer : AbstractionId.id option * borrow_ids option)
+      (borrowed_value : typed_value option) =
     (* First, look for outer borrows or abstraction *)
     let outer_abs, outer_borrows = outer in
     (match outer_abs with
@@ -79,31 +76,31 @@ let end_borrow_get_borrow (allowed_abs : V.AbstractionId.id option)
           | None -> ()
           | Some c -> (
               match c with
-              | V.SharedLoan (bids, _) ->
+              | VSharedLoan (bids, _) ->
                   raise (FoundPriority (InnerLoans (Borrows bids)))
-              | V.MutLoan bid -> raise (FoundPriority (InnerLoans (Borrow bid)))
-              ))
+              | VMutLoan bid -> raise (FoundPriority (InnerLoans (Borrow bid))))
+          )
   in
 
   (* The environment is used to keep track of the outer loans *)
   let obj =
     object
-      inherit [_] C.map_eval_ctx as super
+      inherit [_] map_eval_ctx as super
 
       (** We reimplement {!visit_Loan} because we may have to update the
           outer borrows *)
-      method! visit_Loan (outer : V.AbstractionId.id option * borrow_ids option)
+      method! visit_VLoan (outer : AbstractionId.id option * borrow_ids option)
           lc =
         match lc with
-        | V.MutLoan bid -> V.Loan (super#visit_MutLoan outer bid)
-        | V.SharedLoan (bids, v) ->
+        | VMutLoan bid -> VLoan (super#visit_VMutLoan outer bid)
+        | VSharedLoan (bids, v) ->
             (* Update the outer borrows before diving into the shared value *)
             let outer = update_outer_borrows outer (Borrows bids) in
-            V.Loan (super#visit_SharedLoan outer bids v)
+            VLoan (super#visit_VSharedLoan outer bids v)
 
-      method! visit_Borrow outer bc =
+      method! visit_VBorrow outer bc =
         match bc with
-        | SharedBorrow l' | ReservedMutBorrow l' ->
+        | VSharedBorrow l' | VReservedMutBorrow l' ->
             (* Check if this is the borrow we are looking for *)
             if l = l' then (
               (* Check if there are outer borrows or if we are inside an abstraction *)
@@ -111,9 +108,9 @@ let end_borrow_get_borrow (allowed_abs : V.AbstractionId.id option)
               (* Register the update *)
               set_replaced_bc (fst outer) (Concrete bc);
               (* Update the value *)
-              V.Bottom)
-            else super#visit_Borrow outer bc
-        | V.MutBorrow (l', bv) ->
+              VBottom)
+            else super#visit_VBorrow outer bc
+        | VMutBorrow (l', bv) ->
             (* Check if this is the borrow we are looking for *)
             if l = l' then (
               (* Check if there are outer borrows or if we are inside an abstraction *)
@@ -121,11 +118,11 @@ let end_borrow_get_borrow (allowed_abs : V.AbstractionId.id option)
               (* Register the update *)
               set_replaced_bc (fst outer) (Concrete bc);
               (* Update the value *)
-              V.Bottom)
+              VBottom)
             else
               (* Update the outer borrows before diving into the borrowed value *)
               let outer = update_outer_borrows outer (Borrow l') in
-              V.Borrow (super#visit_MutBorrow outer l' bv)
+              VBorrow (super#visit_VMutBorrow outer l' bv)
 
       (** We reimplement {!visit_ALoan} because we may have to update the
           outer borrows *)
@@ -136,31 +133,31 @@ let end_borrow_get_borrow (allowed_abs : V.AbstractionId.id option)
          * need it to properly instantiate the backward functions when generating
          * the pure translation. *)
         match lc with
-        | V.AMutLoan (_, _) ->
+        | AMutLoan (_, _) ->
             (* Nothing special to do *)
             super#visit_ALoan outer lc
-        | V.ASharedLoan (bids, v, av) ->
+        | ASharedLoan (bids, v, av) ->
             (* Explore the shared value - we need to update the outer borrows *)
             let souter = update_outer_borrows outer (Borrows bids) in
             let v = super#visit_typed_value souter v in
             (* Explore the child avalue - we keep the same outer borrows *)
             let av = super#visit_typed_avalue outer av in
             (* Reconstruct *)
-            V.ALoan (V.ASharedLoan (bids, v, av))
-        | V.AEndedMutLoan { given_back = _; child = _; given_back_meta = _ }
-        | V.AEndedSharedLoan _
+            ALoan (ASharedLoan (bids, v, av))
+        | AEndedMutLoan { given_back = _; child = _; given_back_meta = _ }
+        | AEndedSharedLoan _
         (* The loan has ended, so no need to update the outer borrows *)
-        | V.AIgnoredMutLoan _ (* Nothing special to do *)
-        | V.AEndedIgnoredMutLoan
+        | AIgnoredMutLoan _ (* Nothing special to do *)
+        | AEndedIgnoredMutLoan
             { given_back = _; child = _; given_back_meta = _ }
         (* Nothing special to do *)
-        | V.AIgnoredSharedLoan _ ->
+        | AIgnoredSharedLoan _ ->
             (* Nothing special to do *)
             super#visit_ALoan outer lc
 
       method! visit_ABorrow outer bc =
         match bc with
-        | V.AMutBorrow (bid, _) ->
+        | AMutBorrow (bid, _) ->
             (* Check if this is the borrow we are looking for *)
             if bid = l then (
               (* TODO: treat this case differently. We should not introduce
@@ -184,12 +181,12 @@ let end_borrow_get_borrow (allowed_abs : V.AbstractionId.id option)
                * abstraction (and not really giving the value back to the context)
                * we do not insert {!AEndedMutBorrow} but rather {!ABottom} *)
               raise (Failure "Unimplemented")
-              (* V.ABottom *))
+              (* ABottom *))
             else
               (* Update the outer borrows before diving into the child avalue *)
               let outer = update_outer_borrows outer (Borrow bid) in
               super#visit_ABorrow outer bc
-        | V.ASharedBorrow bid ->
+        | ASharedBorrow bid ->
             (* Check if this is the borrow we are looking for *)
             if bid = l then (
               (* Check there are outer borrows, or if we need to end the whole
@@ -199,16 +196,16 @@ let end_borrow_get_borrow (allowed_abs : V.AbstractionId.id option)
               set_replaced_bc (fst outer) (Abstract bc);
               (* Update the value - note that we are necessarily in the second
                * of the two cases described above *)
-              V.ABottom)
+              ABottom)
             else super#visit_ABorrow outer bc
-        | V.AIgnoredMutBorrow (_, _)
-        | V.AEndedMutBorrow _
-        | V.AEndedIgnoredMutBorrow
+        | AIgnoredMutBorrow (_, _)
+        | AEndedMutBorrow _
+        | AEndedIgnoredMutBorrow
             { given_back = _; child = _; given_back_meta = _ }
-        | V.AEndedSharedBorrow ->
+        | AEndedSharedBorrow ->
             (* Nothing special to do *)
             super#visit_ABorrow outer bc
-        | V.AProjSharedBorrow asb ->
+        | AProjSharedBorrow asb ->
             (* Check if the borrow we are looking for is in the asb *)
             if borrow_in_asb l asb then (
               (* Check there are outer borrows, or if we need to end the whole
@@ -219,7 +216,7 @@ let end_borrow_get_borrow (allowed_abs : V.AbstractionId.id option)
               (* Update the value - note that we are necessarily in the second
                * of the two cases described above *)
               let asb = remove_borrow_from_asb l asb in
-              V.ABorrow (V.AProjSharedBorrow asb))
+              ABorrow (AProjSharedBorrow asb))
             else (* Nothing special to do *)
               super#visit_ABorrow outer bc
 
@@ -228,7 +225,7 @@ let end_borrow_get_borrow (allowed_abs : V.AbstractionId.id option)
         let outer_abs, outer_borrows = outer in
         assert (Option.is_none outer_abs);
         assert (Option.is_none outer_borrows);
-        let outer = (Some abs.V.abs_id, None) in
+        let outer = (Some abs.abs_id, None) in
         super#visit_abs outer abs
     end
   in
@@ -247,15 +244,15 @@ let end_borrow_get_borrow (allowed_abs : V.AbstractionId.id option)
     give the value back.
     TODO: this was not the case before, so some sanity checks are not useful anymore.
  *)
-let give_back_value (config : C.config) (bid : V.BorrowId.id)
-    (nv : V.typed_value) (ctx : C.eval_ctx) : C.eval_ctx =
+let give_back_value (config : config) (bid : BorrowId.id) (nv : typed_value)
+    (ctx : eval_ctx) : eval_ctx =
   (* Sanity check *)
   assert (not (loans_in_value nv));
   assert (not (bottom_in_value ctx.ended_regions nv));
   (* Debug *)
   log#ldebug
     (lazy
-      ("give_back_value:\n- bid: " ^ V.BorrowId.to_string bid ^ "\n- value: "
+      ("give_back_value:\n- bid: " ^ BorrowId.to_string bid ^ "\n- value: "
       ^ typed_value_to_string ctx nv
       ^ "\n- context:\n" ^ eval_ctx_to_string ctx ^ "\n"));
   (* We use a reference to check that we updated exactly one loan *)
@@ -274,66 +271,65 @@ let give_back_value (config : C.config) (bid : V.BorrowId.id)
   (* The visitor to give back the values *)
   let obj =
     object (self)
-      inherit [_] C.map_eval_ctx as super
+      inherit [_] map_eval_ctx as super
 
       (** This is a bit annoying, but as we need the type of the value we
           are exploring, for sanity checks, we need to implement
           {!visit_typed_avalue} instead of
           overriding {!visit_ALoan} *)
-      method! visit_typed_value opt_abs (v : V.typed_value) : V.typed_value =
-        match v.V.value with
-        | V.Loan lc ->
-            let value = self#visit_typed_Loan opt_abs v.V.ty lc in
-            ({ v with V.value } : V.typed_value)
+      method! visit_typed_value opt_abs (v : typed_value) : typed_value =
+        match v.value with
+        | VLoan lc ->
+            let value = self#visit_typed_Loan opt_abs v.ty lc in
+            ({ v with value } : typed_value)
         | _ -> super#visit_typed_value opt_abs v
 
       method visit_typed_Loan opt_abs ty lc =
         match lc with
-        | V.SharedLoan (bids, v) ->
+        | VSharedLoan (bids, v) ->
             (* We are giving back a value (i.e., the content of a *mutable*
              * borrow): nothing special to do *)
-            V.Loan (super#visit_SharedLoan opt_abs bids v)
-        | V.MutLoan bid' ->
+            VLoan (super#visit_VSharedLoan opt_abs bids v)
+        | VMutLoan bid' ->
             (* Check if this is the loan we are looking for *)
             if bid' = bid then (
               (* Sanity check *)
               let expected_ty = ty in
-              if nv.V.ty <> expected_ty then (
+              if nv.ty <> expected_ty then (
                 log#serror
                   ("give_back_value: improper type:\n- expected: "
-                 ^ ety_to_string ctx ty ^ "\n- received: "
-                 ^ ety_to_string ctx nv.V.ty);
+                 ^ ty_to_string ctx ty ^ "\n- received: "
+                 ^ ty_to_string ctx nv.ty);
                 raise (Failure "Value given back doesn't have the proper type"));
               (* Replace *)
               set_replaced ();
-              nv.V.value)
-            else V.Loan (super#visit_MutLoan opt_abs bid')
+              nv.value)
+            else VLoan (super#visit_VMutLoan opt_abs bid')
 
       (** This is a bit annoying, but as we need the type of the avalue we
           are exploring, in order to be able to project the value we give
           back, we need to reimplement {!visit_typed_avalue} instead of
           {!visit_ALoan} *)
-      method! visit_typed_avalue opt_abs (av : V.typed_avalue) : V.typed_avalue
-          =
-        match av.V.value with
-        | V.ALoan lc ->
-            let value = self#visit_typed_ALoan opt_abs av.V.ty lc in
-            ({ av with V.value } : V.typed_avalue)
+      method! visit_typed_avalue opt_abs (av : typed_avalue) : typed_avalue =
+        match av.value with
+        | ALoan lc ->
+            let value = self#visit_typed_ALoan opt_abs av.ty lc in
+            ({ av with value } : typed_avalue)
         | _ -> super#visit_typed_avalue opt_abs av
 
       (** We need to inspect ignored mutable borrows, to insert loan projectors
           if necessary.
        *)
-      method! visit_ABorrow (opt_abs : V.abs option) (bc : V.aborrow_content)
-          : V.avalue =
+      method! visit_ABorrow (opt_abs : abs option) (bc : aborrow_content)
+          : avalue =
         match bc with
-        | V.AIgnoredMutBorrow (bid', child) ->
+        | AIgnoredMutBorrow (bid', child) ->
             if bid' = Some bid then
               (* Insert a loans projector - note that if this case happens,
                * it is necessarily because we ended a parent abstraction,
                * and the given back value is thus a symbolic value *)
-              match nv.V.value with
-              | V.Symbolic sv ->
+              match nv.value with
+              | VSymbolic sv ->
                   let abs = Option.get opt_abs in
                   (* Remember the given back value as a meta-value
                    * TODO: it is a bit annoying to have to deconstruct
@@ -346,26 +342,26 @@ let give_back_value (config : C.config) (bid : V.BorrowId.id)
                   (* Continue giving back in the child value *)
                   let child = super#visit_typed_avalue opt_abs child in
                   (* Return *)
-                  V.ABorrow
-                    (V.AEndedIgnoredMutBorrow
+                  ABorrow
+                    (AEndedIgnoredMutBorrow
                        { given_back; child; given_back_meta })
               | _ -> raise (Failure "Unreachable")
             else
               (* Continue exploring *)
-              V.ABorrow (super#visit_AIgnoredMutBorrow opt_abs bid' child)
+              ABorrow (super#visit_AIgnoredMutBorrow opt_abs bid' child)
         | _ ->
             (* Continue exploring *)
             super#visit_ABorrow opt_abs bc
 
       (** We are not specializing an already existing method, but adding a
           new method (for projections, we need type information) *)
-      method visit_typed_ALoan (opt_abs : V.abs option) (ty : T.rty)
-          (lc : V.aloan_content) : V.avalue =
+      method visit_typed_ALoan (opt_abs : abs option) (ty : rty)
+          (lc : aloan_content) : avalue =
         (* Preparing a bit *)
         let regions, ancestors_regions =
           match opt_abs with
           | None -> raise (Failure "Unreachable")
-          | Some abs -> (abs.V.regions, abs.V.ancestors_regions)
+          | Some abs -> (abs.regions, abs.ancestors_regions)
         in
         (* Rk.: there is a small issue with the types of the aloan values.
          * See the comment at the level of definition of {!typed_avalue} *)
@@ -374,7 +370,7 @@ let give_back_value (config : C.config) (bid : V.BorrowId.id)
           ty
         in
         match lc with
-        | V.AMutLoan (bid', child) ->
+        | AMutLoan (bid', child) ->
             if bid' = bid then (
               (* This is the loan we are looking for: apply the projection to
                * the value we give back and replaced this mutable loan with
@@ -391,17 +387,17 @@ let give_back_value (config : C.config) (bid : V.BorrowId.id)
               (* Continue giving back in the child value *)
               let child = super#visit_typed_avalue opt_abs child in
               (* Return the new value *)
-              V.ALoan (V.AEndedMutLoan { child; given_back; given_back_meta }))
+              ALoan (AEndedMutLoan { child; given_back; given_back_meta }))
             else (* Continue exploring *)
               super#visit_ALoan opt_abs lc
-        | V.ASharedLoan (_, _, _) ->
+        | ASharedLoan (_, _, _) ->
             (* We are giving back a value to a *mutable* loan: nothing special to do *)
             super#visit_ALoan opt_abs lc
-        | V.AEndedMutLoan { child = _; given_back = _; given_back_meta = _ }
-        | V.AEndedSharedLoan (_, _) ->
+        | AEndedMutLoan { child = _; given_back = _; given_back_meta = _ }
+        | AEndedSharedLoan (_, _) ->
             (* Nothing special to do *)
             super#visit_ALoan opt_abs lc
-        | V.AIgnoredMutLoan (opt_bid, child) ->
+        | AIgnoredMutLoan (opt_bid, child) ->
             (* This loan is ignored, but we may have to project on a subvalue
              * of the value which is given back *)
             if opt_bid = Some bid then
@@ -417,21 +413,21 @@ let give_back_value (config : C.config) (bid : V.BorrowId.id)
               in
               (* Continue giving back in the child value *)
               let child = super#visit_typed_avalue opt_abs child in
-              V.ALoan
-                (V.AEndedIgnoredMutLoan { given_back; child; given_back_meta })
+              ALoan
+                (AEndedIgnoredMutLoan { given_back; child; given_back_meta })
             else super#visit_ALoan opt_abs lc
-        | V.AEndedIgnoredMutLoan
+        | AEndedIgnoredMutLoan
             { given_back = _; child = _; given_back_meta = _ }
-        | V.AIgnoredSharedLoan _ ->
+        | AIgnoredSharedLoan _ ->
             (* Nothing special to do *)
             super#visit_ALoan opt_abs lc
 
-      method! visit_Abs opt_abs abs =
+      method! visit_EAbs opt_abs abs =
         (* We remember in which abstraction we are before diving -
          * this is necessary for projecting values: we need to know
          * over which regions to project *)
         assert (Option.is_none opt_abs);
-        super#visit_Abs (Some abs) abs
+        super#visit_EAbs (Some abs) abs
     end
   in
 
@@ -443,13 +439,13 @@ let give_back_value (config : C.config) (bid : V.BorrowId.id)
   apply_registered_reborrows ctx
 
 (** Give back a *modified* symbolic value. *)
-let give_back_symbolic_value (_config : C.config)
-    (proj_regions : T.RegionId.Set.t) (proj_ty : T.rty) (sv : V.symbolic_value)
-    (nsv : V.symbolic_value) (ctx : C.eval_ctx) : C.eval_ctx =
+let give_back_symbolic_value (_config : config) (proj_regions : RegionId.Set.t)
+    (proj_ty : rty) (sv : symbolic_value) (nsv : symbolic_value)
+    (ctx : eval_ctx) : eval_ctx =
   (* Sanity checks *)
-  assert (sv.sv_id <> nsv.sv_id);
+  assert (sv.sv_id <> nsv.sv_id && ty_is_rty proj_ty);
   (match nsv.sv_kind with
-  | V.SynthInputGivenBack | SynthRetGivenBack | FunCallGivenBack | LoopGivenBack
+  | SynthInputGivenBack | SynthRetGivenBack | FunCallGivenBack | LoopGivenBack
     ->
       ()
   | FunCallRet | SynthInput | Global | LoopOutput | LoopJoin | Aggregate
@@ -458,13 +454,13 @@ let give_back_symbolic_value (_config : C.config)
   (* Store the given-back value as a meta-value for synthesis purposes *)
   let mv = nsv in
   (* Substitution function, to replace the borrow projectors over symbolic values *)
-  let subst (_abs : V.abs) local_given_back =
+  let subst (_abs : abs) local_given_back =
     (* See the below comments: there is something wrong here *)
     let _ = raise Utils.Unimplemented in
     (* Compute the projection over the given back value *)
     let child_proj =
       match nsv.sv_kind with
-      | V.SynthRetGivenBack ->
+      | SynthRetGivenBack ->
           (* The given back value comes from the return value of the function
              we are currently synthesizing (as it is given back, it means
              we ended one of the regions appearing in the signature: we are
@@ -472,8 +468,8 @@ let give_back_symbolic_value (_config : C.config)
 
              As we don't allow borrow overwrites on returned value, we can
              (and MUST) forget the borrows *)
-          V.AIgnoredProjBorrows
-      | V.FunCallGivenBack ->
+          AIgnoredProjBorrows
+      | FunCallGivenBack ->
           (* TODO: there is something wrong here.
              Consider this:
              {[
@@ -486,16 +482,16 @@ let give_back_symbolic_value (_config : C.config)
              borrow in the type [&'a mut T] was ended: we give back a value of
              type [T]! We thus *mustn't* introduce a projector here.
           *)
-          V.AProjBorrows (nsv, sv.V.sv_ty)
+          AProjBorrows (nsv, sv.sv_ty)
       | _ -> raise (Failure "Unreachable")
     in
-    V.AProjLoans (sv, (mv, child_proj) :: local_given_back)
+    AProjLoans (sv, (mv, child_proj) :: local_given_back)
   in
   update_intersecting_aproj_loans proj_regions proj_ty sv subst ctx
 
 (** Auxiliary function to end borrows. See {!give_back}.
 
-    This function is similar to {!give_back_value} but gives back an {!V.avalue}
+    This function is similar to {!give_back_value} but gives back an {!avalue}
     (coming from an abstraction).
 
     It is used when ending a borrow inside an abstraction, when the corresponding
@@ -504,11 +500,10 @@ let give_back_symbolic_value (_config : C.config)
     
     REMARK: this function can't be used to give back the values borrowed by
     end abstraction when ending this abstraction. When doing this, we need
-    to convert the {!V.avalue} to a {!type:V.value} by introducing the proper symbolic values.
+    to convert the {!avalue} to a {!type:value} by introducing the proper symbolic values.
  *)
-let give_back_avalue_to_same_abstraction (_config : C.config)
-    (bid : V.BorrowId.id) (nv : V.typed_avalue) (nsv : V.typed_value)
-    (ctx : C.eval_ctx) : C.eval_ctx =
+let give_back_avalue_to_same_abstraction (_config : config) (bid : BorrowId.id)
+    (nv : typed_avalue) (nsv : typed_value) (ctx : eval_ctx) : eval_ctx =
   (* We use a reference to check that we updated exactly one loan *)
   let replaced : bool ref = ref false in
   let set_replaced () =
@@ -517,7 +512,7 @@ let give_back_avalue_to_same_abstraction (_config : C.config)
   in
   let obj =
     object (self)
-      inherit [_] C.map_eval_ctx as super
+      inherit [_] map_eval_ctx as super
 
       (** This is a bit annoying, but as we need the type of the avalue we
           are exploring, in order to be able to project the value we give
@@ -527,12 +522,11 @@ let give_back_avalue_to_same_abstraction (_config : C.config)
           TODO: it is possible to do this by remembering the type of the last
           typed avalue we entered.
        *)
-      method! visit_typed_avalue opt_abs (av : V.typed_avalue) : V.typed_avalue
-          =
-        match av.V.value with
-        | V.ALoan lc ->
-            let value = self#visit_typed_ALoan opt_abs av.V.ty lc in
-            ({ av with V.value } : V.typed_avalue)
+      method! visit_typed_avalue opt_abs (av : typed_avalue) : typed_avalue =
+        match av.value with
+        | ALoan lc ->
+            let value = self#visit_typed_ALoan opt_abs av.ty lc in
+            ({ av with value } : typed_avalue)
         | _ -> super#visit_typed_avalue opt_abs av
 
       (** We are not specializing an already existing method, but adding a
@@ -541,21 +535,21 @@ let give_back_avalue_to_same_abstraction (_config : C.config)
           TODO: it is possible to do this by remembering the type of the last
           typed avalue we entered.
         *)
-      method visit_typed_ALoan (opt_abs : V.abs option) (ty : T.rty)
-          (lc : V.aloan_content) : V.avalue =
+      method visit_typed_ALoan (opt_abs : abs option) (ty : rty)
+          (lc : aloan_content) : avalue =
         match lc with
-        | V.AMutLoan (bid', child) ->
+        | AMutLoan (bid', child) ->
             if bid' = bid then (
               (* Sanity check - about why we need to call {!ty_get_ref}
                * (and don't do the same thing as in {!give_back_value})
                * see the comment at the level of the definition of
                * {!typed_avalue} *)
               let _, expected_ty, _ = ty_get_ref ty in
-              if nv.V.ty <> expected_ty then (
+              if nv.ty <> expected_ty then (
                 log#serror
                   ("give_back_avalue_to_same_abstraction: improper type:\n\
-                    - expected: " ^ rty_to_string ctx ty ^ "\n- received: "
-                 ^ rty_to_string ctx nv.V.ty);
+                    - expected: " ^ ty_to_string ctx ty ^ "\n- received: "
+                 ^ ty_to_string ctx nv.ty);
                 raise (Failure "Value given back doesn't have the proper type"));
               (* This is the loan we are looking for: apply the projection to
                * the value we give back and replaced this mutable loan with
@@ -563,18 +557,17 @@ let give_back_avalue_to_same_abstraction (_config : C.config)
               (* Register the insertion *)
               set_replaced ();
               (* Return the new value *)
-              V.ALoan
-                (V.AEndedMutLoan
-                   { given_back = nv; child; given_back_meta = nsv }))
+              ALoan
+                (AEndedMutLoan { given_back = nv; child; given_back_meta = nsv }))
             else (* Continue exploring *)
               super#visit_ALoan opt_abs lc
-        | V.ASharedLoan (_, _, _)
+        | ASharedLoan (_, _, _)
         (* We are giving back a value to a *mutable* loan: nothing special to do *)
-        | V.AEndedMutLoan { given_back = _; child = _; given_back_meta = _ }
-        | V.AEndedSharedLoan (_, _) ->
+        | AEndedMutLoan { given_back = _; child = _; given_back_meta = _ }
+        | AEndedSharedLoan (_, _) ->
             (* Nothing special to do *)
             super#visit_ALoan opt_abs lc
-        | V.AIgnoredMutLoan (bid_opt, child) ->
+        | AIgnoredMutLoan (bid_opt, child) ->
             (* This loan is ignored, but we may have to project on a subvalue
              * of the value which is given back *)
             if bid_opt = Some bid then (
@@ -583,14 +576,14 @@ let give_back_avalue_to_same_abstraction (_config : C.config)
                * we don't register the fact that we inserted the value somewhere
                * (i.e., we don't call {!set_replaced}) *)
               (* Sanity check *)
-              assert (nv.V.ty = ty);
-              V.ALoan
-                (V.AEndedIgnoredMutLoan
+              assert (nv.ty = ty);
+              ALoan
+                (AEndedIgnoredMutLoan
                    { given_back = nv; child; given_back_meta = nsv }))
             else super#visit_ALoan opt_abs lc
-        | V.AEndedIgnoredMutLoan
+        | AEndedIgnoredMutLoan
             { given_back = _; child = _; given_back_meta = _ }
-        | V.AIgnoredSharedLoan _ ->
+        | AIgnoredSharedLoan _ ->
             (* Nothing special to do *)
             super#visit_ALoan opt_abs lc
     end
@@ -612,8 +605,7 @@ let give_back_avalue_to_same_abstraction (_config : C.config)
     we update.
     TODO: this was not the case before, so some sanity checks are not useful anymore.
  *)
-let give_back_shared _config (bid : V.BorrowId.id) (ctx : C.eval_ctx) :
-    C.eval_ctx =
+let give_back_shared _config (bid : BorrowId.id) (ctx : eval_ctx) : eval_ctx =
   (* We use a reference to check that we updated exactly one loan *)
   let replaced : bool ref = ref false in
   let set_replaced () =
@@ -622,59 +614,58 @@ let give_back_shared _config (bid : V.BorrowId.id) (ctx : C.eval_ctx) :
   in
   let obj =
     object
-      inherit [_] C.map_eval_ctx as super
+      inherit [_] map_eval_ctx as super
 
-      method! visit_Loan opt_abs lc =
+      method! visit_VLoan opt_abs lc =
         match lc with
-        | V.SharedLoan (bids, shared_value) ->
-            if V.BorrowId.Set.mem bid bids then (
+        | VSharedLoan (bids, shared_value) ->
+            if BorrowId.Set.mem bid bids then (
               (* This is the loan we are looking for *)
               set_replaced ();
               (* If there remains exactly one borrow identifier, we need
                * to end the loan. Otherwise, we just remove the current
                * loan identifier *)
-              if V.BorrowId.Set.cardinal bids = 1 then shared_value.V.value
+              if BorrowId.Set.cardinal bids = 1 then shared_value.value
               else
-                V.Loan
-                  (V.SharedLoan (V.BorrowId.Set.remove bid bids, shared_value)))
+                VLoan (VSharedLoan (BorrowId.Set.remove bid bids, shared_value)))
             else
               (* Not the loan we are looking for: continue exploring *)
-              V.Loan (super#visit_SharedLoan opt_abs bids shared_value)
-        | V.MutLoan bid' ->
+              VLoan (super#visit_VSharedLoan opt_abs bids shared_value)
+        | VMutLoan bid' ->
             (* We are giving back a *shared* borrow: nothing special to do *)
-            V.Loan (super#visit_MutLoan opt_abs bid')
+            VLoan (super#visit_VMutLoan opt_abs bid')
 
       method! visit_ALoan opt_abs lc =
         match lc with
-        | V.AMutLoan (bid, av) ->
+        | AMutLoan (bid, av) ->
             (* Nothing special to do (we are giving back a *shared* borrow) *)
-            V.ALoan (super#visit_AMutLoan opt_abs bid av)
-        | V.ASharedLoan (bids, shared_value, child) ->
-            if V.BorrowId.Set.mem bid bids then (
+            ALoan (super#visit_AMutLoan opt_abs bid av)
+        | ASharedLoan (bids, shared_value, child) ->
+            if BorrowId.Set.mem bid bids then (
               (* This is the loan we are looking for *)
               set_replaced ();
               (* If there remains exactly one borrow identifier, we need
                * to end the loan. Otherwise, we just remove the current
                * loan identifier *)
-              if V.BorrowId.Set.cardinal bids = 1 then
-                V.ALoan (V.AEndedSharedLoan (shared_value, child))
+              if BorrowId.Set.cardinal bids = 1 then
+                ALoan (AEndedSharedLoan (shared_value, child))
               else
-                V.ALoan
-                  (V.ASharedLoan
-                     (V.BorrowId.Set.remove bid bids, shared_value, child)))
+                ALoan
+                  (ASharedLoan
+                     (BorrowId.Set.remove bid bids, shared_value, child)))
             else
               (* Not the loan we are looking for: continue exploring *)
               super#visit_ALoan opt_abs lc
-        | V.AEndedMutLoan { given_back = _; child = _; given_back_meta = _ }
+        | AEndedMutLoan { given_back = _; child = _; given_back_meta = _ }
         (* Nothing special to do (the loan has ended) *)
-        | V.AEndedSharedLoan (_, _)
+        | AEndedSharedLoan (_, _)
         (* Nothing special to do (the loan has ended) *)
-        | V.AIgnoredMutLoan (_, _)
+        | AIgnoredMutLoan (_, _)
         (* Nothing special to do (we are giving back a *shared* borrow) *)
-        | V.AEndedIgnoredMutLoan
+        | AEndedIgnoredMutLoan
             { given_back = _; child = _; given_back_meta = _ }
         (* Nothing special to do *)
-        | V.AIgnoredSharedLoan _ ->
+        | AIgnoredSharedLoan _ ->
             (* Nothing special to do *)
             super#visit_ALoan opt_abs lc
     end
@@ -692,8 +683,8 @@ let give_back_shared _config (bid : V.BorrowId.id) (ctx : C.eval_ctx) :
     to an environment by inserting a new borrow id in the set of borrows tracked
     by a shared value, referenced by the [original_bid] argument.
  *)
-let reborrow_shared (original_bid : V.BorrowId.id) (new_bid : V.BorrowId.id)
-    (ctx : C.eval_ctx) : C.eval_ctx =
+let reborrow_shared (original_bid : BorrowId.id) (new_bid : BorrowId.id)
+    (ctx : eval_ctx) : eval_ctx =
   (* Keep track of changes *)
   let r = ref false in
   let set_ref () =
@@ -703,24 +694,24 @@ let reborrow_shared (original_bid : V.BorrowId.id) (new_bid : V.BorrowId.id)
 
   let obj =
     object
-      inherit [_] C.map_env as super
+      inherit [_] map_env as super
 
-      method! visit_SharedLoan env bids sv =
+      method! visit_VSharedLoan env bids sv =
         (* Shared loan: check if the borrow id we are looking for is in the
            set of borrow ids. If yes, insert the new borrow id, otherwise
            explore inside the shared value *)
-        if V.BorrowId.Set.mem original_bid bids then (
+        if BorrowId.Set.mem original_bid bids then (
           set_ref ();
-          let bids' = V.BorrowId.Set.add new_bid bids in
-          V.SharedLoan (bids', sv))
-        else super#visit_SharedLoan env bids sv
+          let bids' = BorrowId.Set.add new_bid bids in
+          VSharedLoan (bids', sv))
+        else super#visit_VSharedLoan env bids sv
 
       method! visit_ASharedLoan env bids v av =
         (* This case is similar to the {!SharedLoan} case *)
-        if V.BorrowId.Set.mem original_bid bids then (
+        if BorrowId.Set.mem original_bid bids then (
           set_ref ();
-          let bids' = V.BorrowId.Set.add new_bid bids in
-          V.ASharedLoan (bids', v, av))
+          let bids' = BorrowId.Set.add new_bid bids in
+          ASharedLoan (bids', v, av))
         else super#visit_ASharedLoan env bids v av
     end
   in
@@ -730,11 +721,11 @@ let reborrow_shared (original_bid : V.BorrowId.id) (new_bid : V.BorrowId.id)
   assert !r;
   { ctx with env }
 
-(** Convert an {!type:V.avalue} to a {!type:V.value}.
+(** Convert an {!type:avalue} to a {!type:value}.
 
     This function is used when ending abstractions: whenever we end a borrow
-    in an abstraction, we converted the borrowed {!V.avalue} to a fresh symbolic
-    {!type:V.value}, then give back this {!type:V.value} to the context.
+    in an abstraction, we converted the borrowed {!avalue} to a fresh symbolic
+    {!type:value}, then give back this {!type:value} to the context.
 
     Note that some regions may have ended in the symbolic value we generate.
     For instance, consider the following function signature:
@@ -746,19 +737,19 @@ let reborrow_shared (original_bid : V.BorrowId.id) (new_bid : V.BorrowId.id)
     be expanded (because expanding this symbolic value would require expanding
     a reference whose region has already ended).
  *)
-let convert_avalue_to_given_back_value (abs_kind : V.abs_kind)
-    (av : V.typed_avalue) : V.symbolic_value =
+let convert_avalue_to_given_back_value (abs_kind : abs_kind) (av : typed_avalue)
+    : symbolic_value =
   let sv_kind =
     match abs_kind with
-    | V.FunCall _ -> V.FunCallGivenBack
-    | V.SynthRet _ -> V.SynthRetGivenBack
-    | V.SynthInput _ -> V.SynthInputGivenBack
-    | V.Loop _ -> V.LoopGivenBack
-    | V.Identity ->
+    | FunCall _ -> FunCallGivenBack
+    | SynthRet _ -> SynthRetGivenBack
+    | SynthInput _ -> SynthInputGivenBack
+    | Loop _ -> LoopGivenBack
+    | Identity ->
         (* Identity abstractions give back nothing *)
         raise (Failure "Unreachable")
   in
-  mk_fresh_symbolic_value sv_kind av.V.ty
+  mk_fresh_symbolic_value sv_kind av.ty
 
 (** Auxiliary function: see {!end_borrow_aux}.
 
@@ -776,9 +767,8 @@ let convert_avalue_to_given_back_value (abs_kind : V.abs_kind)
     borrows. This kind of internal reshuffling. should be similar to ending
     abstractions (it is tantamount to ending *sub*-abstractions).
  *)
-let give_back (config : C.config) (abs_id_opt : V.AbstractionId.id option)
-    (l : V.BorrowId.id) (bc : g_borrow_content) (ctx : C.eval_ctx) : C.eval_ctx
-    =
+let give_back (config : config) (abs_id_opt : AbstractionId.id option)
+    (l : BorrowId.id) (bc : g_borrow_content) (ctx : eval_ctx) : eval_ctx =
   (* Debug *)
   log#ldebug
     (lazy
@@ -787,14 +777,14 @@ let give_back (config : C.config) (abs_id_opt : V.AbstractionId.id option)
          | Concrete bc -> borrow_content_to_string ctx bc
          | Abstract bc -> aborrow_content_to_string ctx bc
        in
-       "give_back:\n- bid: " ^ V.BorrowId.to_string l ^ "\n- content: " ^ bc
+       "give_back:\n- bid: " ^ BorrowId.to_string l ^ "\n- content: " ^ bc
        ^ "\n- context:\n" ^ eval_ctx_to_string ctx ^ "\n"));
   (* This is used for sanity checks *)
   let sanity_ek =
     { enter_shared_loans = true; enter_mut_borrows = true; enter_abs = true }
   in
   match bc with
-  | Concrete (V.MutBorrow (l', tv)) ->
+  | Concrete (VMutBorrow (l', tv)) ->
       (* Sanity check *)
       assert (l' = l);
       assert (not (loans_in_value tv));
@@ -802,14 +792,14 @@ let give_back (config : C.config) (abs_id_opt : V.AbstractionId.id option)
       assert (Option.is_some (lookup_loan_opt sanity_ek l ctx));
       (* Update the context *)
       give_back_value config l tv ctx
-  | Concrete (V.SharedBorrow l' | V.ReservedMutBorrow l') ->
+  | Concrete (VSharedBorrow l' | VReservedMutBorrow l') ->
       (* Sanity check *)
       assert (l' = l);
       (* Check that the borrow is somewhere - purely a sanity check *)
       assert (Option.is_some (lookup_loan_opt sanity_ek l ctx));
       (* Update the context *)
       give_back_shared config l ctx
-  | Abstract (V.AMutBorrow (l', av)) ->
+  | Abstract (AMutBorrow (l', av)) ->
       (* Sanity check *)
       assert (l' = l);
       (* Check that the corresponding loan is somewhere - purely a sanity check *)
@@ -820,39 +810,39 @@ let give_back (config : C.config) (abs_id_opt : V.AbstractionId.id option)
          which takes care of ending *sub*-abstractions.
       *)
       let abs_id = Option.get abs_id_opt in
-      let abs = C.ctx_lookup_abs ctx abs_id in
+      let abs = ctx_lookup_abs ctx abs_id in
       let sv = convert_avalue_to_given_back_value abs.kind av in
       (* Update the context *)
       give_back_avalue_to_same_abstraction config l av
         (mk_typed_value_from_symbolic_value sv)
         ctx
-  | Abstract (V.ASharedBorrow l') ->
+  | Abstract (ASharedBorrow l') ->
       (* Sanity check *)
       assert (l' = l);
       (* Check that the borrow is somewhere - purely a sanity check *)
       assert (Option.is_some (lookup_loan_opt sanity_ek l ctx));
       (* Update the context *)
       give_back_shared config l ctx
-  | Abstract (V.AProjSharedBorrow asb) ->
+  | Abstract (AProjSharedBorrow asb) ->
       (* Sanity check *)
       assert (borrow_in_asb l asb);
       (* Update the context *)
       give_back_shared config l ctx
   | Abstract
-      ( V.AEndedMutBorrow _ | V.AIgnoredMutBorrow _ | V.AEndedIgnoredMutBorrow _
-      | V.AEndedSharedBorrow ) ->
+      ( AEndedMutBorrow _ | AIgnoredMutBorrow _ | AEndedIgnoredMutBorrow _
+      | AEndedSharedBorrow ) ->
       raise (Failure "Unreachable")
 
-let check_borrow_disappeared (fun_name : string) (l : V.BorrowId.id)
-    (ctx0 : C.eval_ctx) : cm_fun =
-  let check_disappeared (ctx : C.eval_ctx) : unit =
+let check_borrow_disappeared (fun_name : string) (l : BorrowId.id)
+    (ctx0 : eval_ctx) : cm_fun =
+  let check_disappeared (ctx : eval_ctx) : unit =
     let _ =
       match lookup_borrow_opt ek_all l ctx with
       | None -> () (* Ok *)
       | Some _ ->
           log#lerror
             (lazy
-              (fun_name ^ ": " ^ V.BorrowId.to_string l
+              (fun_name ^ ": " ^ BorrowId.to_string l
              ^ ": borrow didn't disappear:\n- original context:\n"
              ^ eval_ctx_to_string ctx0 ^ "\n\n- new context:\n"
              ^ eval_ctx_to_string ctx));
@@ -863,7 +853,7 @@ let check_borrow_disappeared (fun_name : string) (l : V.BorrowId.id)
     | Some _ ->
         log#lerror
           (lazy
-            (fun_name ^ ": " ^ V.BorrowId.to_string l
+            (fun_name ^ ": " ^ BorrowId.to_string l
            ^ ": loan didn't disappear:\n- original context:\n"
            ^ eval_ctx_to_string ctx0 ^ "\n\n- new context:\n"
            ^ eval_ctx_to_string ctx));
@@ -892,8 +882,8 @@ let check_borrow_disappeared (fun_name : string) (l : V.BorrowId.id)
     perform anything smart and is trusted, and another function for the
     book-keeping.
  *)
-let rec end_borrow_aux (config : C.config) (chain : borrow_or_abs_ids)
-    (allowed_abs : V.AbstractionId.id option) (l : V.BorrowId.id) : cm_fun =
+let rec end_borrow_aux (config : config) (chain : borrow_or_abs_ids)
+    (allowed_abs : AbstractionId.id option) (l : BorrowId.id) : cm_fun =
  fun cf ctx ->
   (* Check that we don't loop *)
   let chain0 = chain in
@@ -902,7 +892,7 @@ let rec end_borrow_aux (config : C.config) (chain : borrow_or_abs_ids)
   in
   log#ldebug
     (lazy
-      ("end borrow: " ^ V.BorrowId.to_string l ^ ":\n- original context:\n"
+      ("end borrow: " ^ BorrowId.to_string l ^ ":\n- original context:\n"
      ^ eval_ctx_to_string ctx));
 
   (* Utility function for the sanity checks: check that the borrow disappeared
@@ -928,7 +918,7 @@ let rec end_borrow_aux (config : C.config) (chain : borrow_or_abs_ids)
       (* Debug *)
       log#ldebug
         (lazy
-          ("end borrow: " ^ V.BorrowId.to_string l
+          ("end borrow: " ^ BorrowId.to_string l
          ^ ": found outer borrows/abs or inner loans:"
           ^ show_priority_borrows_or_abs priority));
       (* End the priority borrows, abstractions, then try again to end the target
@@ -970,7 +960,7 @@ let rec end_borrow_aux (config : C.config) (chain : borrow_or_abs_ids)
   | Ok (ctx, Some (abs_id_opt, bc)) ->
       (* Sanity check: the borrowed value shouldn't contain loans *)
       (match bc with
-      | Concrete (V.MutBorrow (_, bv)) ->
+      | Concrete (VMutBorrow (_, bv)) ->
           assert (Option.is_none (get_first_loan_in_value bv))
       | _ -> ());
       (* Give back the value *)
@@ -978,20 +968,19 @@ let rec end_borrow_aux (config : C.config) (chain : borrow_or_abs_ids)
       (* Do a sanity check and continue *)
       cf_check cf ctx
 
-and end_borrows_aux (config : C.config) (chain : borrow_or_abs_ids)
-    (allowed_abs : V.AbstractionId.id option) (lset : V.BorrowId.Set.t) : cm_fun
-    =
+and end_borrows_aux (config : config) (chain : borrow_or_abs_ids)
+    (allowed_abs : AbstractionId.id option) (lset : BorrowId.Set.t) : cm_fun =
  fun cf ->
   (* This is not necessary, but we prefer to reorder the borrow ids,
    * so that we actually end from the smallest id to the highest id - just
    * a matter of taste, and may make debugging easier *)
-  let ids = V.BorrowId.Set.fold (fun id ids -> id :: ids) lset [] in
+  let ids = BorrowId.Set.fold (fun id ids -> id :: ids) lset [] in
   List.fold_left
     (fun cf id -> end_borrow_aux config chain allowed_abs id cf)
     cf ids
 
-and end_abstraction_aux (config : C.config) (chain : borrow_or_abs_ids)
-    (abs_id : V.AbstractionId.id) : cm_fun =
+and end_abstraction_aux (config : config) (chain : borrow_or_abs_ids)
+    (abs_id : AbstractionId.id) : cm_fun =
  fun cf ctx ->
   (* Check that we don't loop *)
   let chain =
@@ -1002,11 +991,11 @@ and end_abstraction_aux (config : C.config) (chain : borrow_or_abs_ids)
   log#ldebug
     (lazy
       ("end_abstraction_aux: "
-      ^ V.AbstractionId.to_string abs_id
+      ^ AbstractionId.to_string abs_id
       ^ "\n- original context:\n" ^ eval_ctx_to_string ctx0));
 
   (* Lookup the abstraction *)
-  let abs = C.ctx_lookup_abs ctx abs_id in
+  let abs = ctx_lookup_abs ctx abs_id in
 
   (* Check that we can end the abstraction *)
   if abs.can_end then ()
@@ -1014,7 +1003,7 @@ and end_abstraction_aux (config : C.config) (chain : borrow_or_abs_ids)
     raise
       (Failure
          ("Can't end abstraction "
-         ^ V.AbstractionId.to_string abs.abs_id
+         ^ AbstractionId.to_string abs.abs_id
          ^ " as it is set as non-endable"));
 
   (* End the parent abstractions first *)
@@ -1024,7 +1013,7 @@ and end_abstraction_aux (config : C.config) (chain : borrow_or_abs_ids)
         log#ldebug
           (lazy
             ("end_abstraction_aux: "
-            ^ V.AbstractionId.to_string abs_id
+            ^ AbstractionId.to_string abs_id
             ^ "\n- context after parent abstractions ended:\n"
             ^ eval_ctx_to_string ctx)))
   in
@@ -1036,7 +1025,7 @@ and end_abstraction_aux (config : C.config) (chain : borrow_or_abs_ids)
         log#ldebug
           (lazy
             ("end_abstraction_aux: "
-            ^ V.AbstractionId.to_string abs_id
+            ^ AbstractionId.to_string abs_id
             ^ "\n- context after loans ended:\n" ^ eval_ctx_to_string ctx)))
   in
 
@@ -1048,9 +1037,7 @@ and end_abstraction_aux (config : C.config) (chain : borrow_or_abs_ids)
    * changes... *)
   let cc =
     comp_update cc (fun ctx ->
-        let ended_regions =
-          T.RegionId.Set.union ctx.ended_regions abs.V.regions
-        in
+        let ended_regions = RegionId.Set.union ctx.ended_regions abs.regions in
         { ctx with ended_regions })
   in
 
@@ -1065,7 +1052,7 @@ and end_abstraction_aux (config : C.config) (chain : borrow_or_abs_ids)
         log#ldebug
           (lazy
             ("end_abstraction_aux: "
-            ^ V.AbstractionId.to_string abs_id
+            ^ AbstractionId.to_string abs_id
             ^ "\n- original context:\n" ^ eval_ctx_to_string ctx0
             ^ "\n\n- new context:\n" ^ eval_ctx_to_string ctx)))
   in
@@ -1076,22 +1063,22 @@ and end_abstraction_aux (config : C.config) (chain : borrow_or_abs_ids)
   (* Apply the continuation *)
   cc cf ctx
 
-and end_abstractions_aux (config : C.config) (chain : borrow_or_abs_ids)
-    (abs_ids : V.AbstractionId.Set.t) : cm_fun =
+and end_abstractions_aux (config : config) (chain : borrow_or_abs_ids)
+    (abs_ids : AbstractionId.Set.t) : cm_fun =
  fun cf ->
   (* This is not necessary, but we prefer to reorder the abstraction ids,
    * so that we actually end from the smallest id to the highest id - just
    * a matter of taste, and may make debugging easier *)
-  let abs_ids = V.AbstractionId.Set.fold (fun id ids -> id :: ids) abs_ids [] in
+  let abs_ids = AbstractionId.Set.fold (fun id ids -> id :: ids) abs_ids [] in
   List.fold_left
     (fun cf id -> end_abstraction_aux config chain id cf)
     cf abs_ids
 
-and end_abstraction_loans (config : C.config) (chain : borrow_or_abs_ids)
-    (abs_id : V.AbstractionId.id) : cm_fun =
+and end_abstraction_loans (config : config) (chain : borrow_or_abs_ids)
+    (abs_id : AbstractionId.id) : cm_fun =
  fun cf ctx ->
   (* Lookup the abstraction *)
-  let abs = C.ctx_lookup_abs ctx abs_id in
+  let abs = ctx_lookup_abs ctx abs_id in
   (* End the first loan we find.
    *
    * We ignore the "ignored mut/shared loans": as we should have already ended
@@ -1121,12 +1108,12 @@ and end_abstraction_loans (config : C.config) (chain : borrow_or_abs_ids)
       (* Continue *)
       cc cf ctx
 
-and end_abstraction_borrows (config : C.config) (chain : borrow_or_abs_ids)
-    (abs_id : V.AbstractionId.id) : cm_fun =
+and end_abstraction_borrows (config : config) (chain : borrow_or_abs_ids)
+    (abs_id : AbstractionId.id) : cm_fun =
  fun cf ctx ->
   log#ldebug
     (lazy
-      ("end_abstraction_borrows: abs_id: " ^ V.AbstractionId.to_string abs_id));
+      ("end_abstraction_borrows: abs_id: " ^ AbstractionId.to_string abs_id));
   (* Note that the abstraction mustn't contain any loans *)
   (* We end the borrows, starting with the *inner* ones. This is important
      when considering nested borrows which have the same lifetime.
@@ -1146,7 +1133,7 @@ and end_abstraction_borrows (config : C.config) (chain : borrow_or_abs_ids)
    *)
   let obj =
     object
-      inherit [_] V.iter_abs as super
+      inherit [_] iter_abs as super
 
       method! visit_aborrow_content env bc =
         (* In-depth exploration *)
@@ -1154,40 +1141,38 @@ and end_abstraction_borrows (config : C.config) (chain : borrow_or_abs_ids)
         (* No exception was raise: we can raise an exception for the
          * current borrow *)
         match bc with
-        | V.AMutBorrow _ | V.ASharedBorrow _ ->
+        | AMutBorrow _ | ASharedBorrow _ ->
             (* Raise an exception *)
             raise (FoundABorrowContent bc)
-        | V.AProjSharedBorrow asb ->
+        | AProjSharedBorrow asb ->
             (* Raise an exception only if the asb contains borrows *)
             if
               List.exists
-                (fun x -> match x with V.AsbBorrow _ -> true | _ -> false)
+                (fun x -> match x with AsbBorrow _ -> true | _ -> false)
                 asb
             then raise (FoundABorrowContent bc)
             else ()
-        | V.AEndedMutBorrow _ | V.AIgnoredMutBorrow _
-        | V.AEndedIgnoredMutBorrow _ | V.AEndedSharedBorrow ->
+        | AEndedMutBorrow _ | AIgnoredMutBorrow _ | AEndedIgnoredMutBorrow _
+        | AEndedSharedBorrow ->
             (* Nothing to do for ignored borrows *)
             ()
 
       method! visit_aproj env sproj =
         (match sproj with
-        | V.AProjLoans _ -> raise (Failure "Unexpected")
-        | V.AProjBorrows (sv, proj_ty) ->
-            raise (FoundAProjBorrows (sv, proj_ty))
-        | V.AEndedProjLoans _ | V.AEndedProjBorrows _ | V.AIgnoredProjBorrows ->
-            ());
+        | AProjLoans _ -> raise (Failure "Unexpected")
+        | AProjBorrows (sv, proj_ty) -> raise (FoundAProjBorrows (sv, proj_ty))
+        | AEndedProjLoans _ | AEndedProjBorrows _ | AIgnoredProjBorrows -> ());
         super#visit_aproj env sproj
 
       (** We may need to end borrows in "regular" values, because of shared values *)
       method! visit_borrow_content _ bc =
         match bc with
-        | V.SharedBorrow _ | V.MutBorrow (_, _) -> raise (FoundBorrowContent bc)
-        | V.ReservedMutBorrow _ -> raise (Failure "Unreachable")
+        | VSharedBorrow _ | VMutBorrow (_, _) -> raise (FoundBorrowContent bc)
+        | VReservedMutBorrow _ -> raise (Failure "Unreachable")
     end
   in
   (* Lookup the abstraction *)
-  let abs = C.ctx_lookup_abs ctx abs_id in
+  let abs = ctx_lookup_abs ctx abs_id in
   try
     (* Explore the abstraction, looking for borrows *)
     obj#visit_abs () abs;
@@ -1202,37 +1187,37 @@ and end_abstraction_borrows (config : C.config) (chain : borrow_or_abs_ids)
           ^ aborrow_content_to_string ctx bc));
       let ctx =
         match bc with
-        | V.AMutBorrow (bid, av) ->
+        | AMutBorrow (bid, av) ->
             (* First, convert the avalue to a (fresh symbolic) value *)
             let sv = convert_avalue_to_given_back_value abs.kind av in
             (* Replace the mut borrow to register the fact that we ended
              * it and store with it the freshly generated given back value *)
-            let ended_borrow = V.ABorrow (V.AEndedMutBorrow (sv, av)) in
+            let ended_borrow = ABorrow (AEndedMutBorrow (sv, av)) in
             let ctx = update_aborrow ek_all bid ended_borrow ctx in
             (* Give the value back *)
             let sv = mk_typed_value_from_symbolic_value sv in
             give_back_value config bid sv ctx
-        | V.ASharedBorrow bid ->
+        | ASharedBorrow bid ->
             (* Replace the shared borrow to account for the fact it ended *)
-            let ended_borrow = V.ABorrow V.AEndedSharedBorrow in
+            let ended_borrow = ABorrow AEndedSharedBorrow in
             let ctx = update_aborrow ek_all bid ended_borrow ctx in
             (* Give back *)
             give_back_shared config bid ctx
-        | V.AProjSharedBorrow asb ->
+        | AProjSharedBorrow asb ->
             (* Retrieve the borrow ids *)
             let bids =
               List.filter_map
                 (fun asb ->
                   match asb with
-                  | V.AsbBorrow bid -> Some bid
-                  | V.AsbProjReborrows (_, _) -> None)
+                  | AsbBorrow bid -> Some bid
+                  | AsbProjReborrows (_, _) -> None)
                 asb
             in
             (* There should be at least one borrow identifier in the set, which we
              * can use to identify the whole set *)
             let repr_bid = List.hd bids in
             (* Replace the shared borrow with Bottom *)
-            let ctx = update_aborrow ek_all repr_bid V.ABottom ctx in
+            let ctx = update_aborrow ek_all repr_bid ABottom ctx in
             (* Give back the shared borrows *)
             let ctx =
               List.fold_left
@@ -1241,8 +1226,8 @@ and end_abstraction_borrows (config : C.config) (chain : borrow_or_abs_ids)
             in
             (* Continue *)
             ctx
-        | V.AEndedMutBorrow _ | V.AIgnoredMutBorrow _
-        | V.AEndedIgnoredMutBorrow _ | V.AEndedSharedBorrow ->
+        | AEndedMutBorrow _ | AIgnoredMutBorrow _ | AEndedIgnoredMutBorrow _
+        | AEndedSharedBorrow ->
             raise (Failure "Unexpected")
       in
       (* Reexplore *)
@@ -1252,11 +1237,11 @@ and end_abstraction_borrows (config : C.config) (chain : borrow_or_abs_ids)
       log#ldebug
         (lazy
           ("end_abstraction_borrows: found aproj borrows: "
-          ^ aproj_to_string ctx (V.AProjBorrows (sv, proj_ty))));
+          ^ aproj_to_string ctx (AProjBorrows (sv, proj_ty))));
       (* Generate a fresh symbolic value *)
-      let nsv = mk_fresh_symbolic_value V.FunCallGivenBack proj_ty in
+      let nsv = mk_fresh_symbolic_value FunCallGivenBack proj_ty in
       (* Replace the proj_borrows - there should be exactly one *)
-      let ended_borrow = V.AEndedProjBorrows nsv in
+      let ended_borrow = AEndedProjBorrows nsv in
       let ctx = update_aproj_borrows abs.abs_id sv ended_borrow ctx in
       (* Give back the symbolic value *)
       let ctx =
@@ -1272,7 +1257,7 @@ and end_abstraction_borrows (config : C.config) (chain : borrow_or_abs_ids)
           ^ borrow_content_to_string ctx bc));
       let ctx =
         match bc with
-        | V.SharedBorrow bid -> (
+        | VSharedBorrow bid -> (
             (* Replace the shared borrow with bottom *)
             let allow_inner_loans = false in
             match
@@ -1282,7 +1267,7 @@ and end_abstraction_borrows (config : C.config) (chain : borrow_or_abs_ids)
             | Ok (ctx, _) ->
                 (* Give back *)
                 give_back_shared config bid ctx)
-        | V.MutBorrow (bid, v) -> (
+        | VMutBorrow (bid, v) -> (
             (* Replace the mut borrow with bottom *)
             let allow_inner_loans = false in
             match
@@ -1293,21 +1278,21 @@ and end_abstraction_borrows (config : C.config) (chain : borrow_or_abs_ids)
                 (* Give the value back - note that the mut borrow was below a
                  * shared borrow: the value is thus unchanged *)
                 give_back_value config bid v ctx)
-        | V.ReservedMutBorrow _ -> raise (Failure "Unreachable")
+        | VReservedMutBorrow _ -> raise (Failure "Unreachable")
       in
       (* Reexplore *)
       end_abstraction_borrows config chain abs_id cf ctx
 
 (** Remove an abstraction from the context, as well as all its references *)
-and end_abstraction_remove_from_context (_config : C.config)
-    (abs_id : V.AbstractionId.id) : cm_fun =
+and end_abstraction_remove_from_context (_config : config)
+    (abs_id : AbstractionId.id) : cm_fun =
  fun cf ctx ->
-  let ctx, abs = C.ctx_remove_abs ctx abs_id in
+  let ctx, abs = ctx_remove_abs ctx abs_id in
   let abs = Option.get abs in
   (* Apply the continuation *)
   let expr = cf ctx in
   (* Synthesize the symbolic AST *)
-  S.synthesize_end_abstraction ctx abs expr
+  SynthesizeSymbolic.synthesize_end_abstraction ctx abs expr
 
 (** End a proj_loan over a symbolic value by ending the proj_borrows which
     intersect this proj_loans.
@@ -1323,9 +1308,9 @@ and end_abstraction_remove_from_context (_config : C.config)
         intersecting proj_borrows, either in the concrete context or in an
         abstraction
 *)
-and end_proj_loans_symbolic (config : C.config) (chain : borrow_or_abs_ids)
-    (abs_id : V.AbstractionId.id) (regions : T.RegionId.Set.t)
-    (sv : V.symbolic_value) : cm_fun =
+and end_proj_loans_symbolic (config : config) (chain : borrow_or_abs_ids)
+    (abs_id : AbstractionId.id) (regions : RegionId.Set.t) (sv : symbolic_value)
+    : cm_fun =
  fun cf ctx ->
   (* Small helpers for sanity checks *)
   let check ctx = no_aproj_over_symbolic_in_context sv ctx in
@@ -1382,8 +1367,8 @@ and end_proj_loans_symbolic (config : C.config) (chain : borrow_or_abs_ids)
         let abs_ids = List.map fst external_projs in
         let abs_ids =
           List.fold_left
-            (fun s id -> V.AbstractionId.Set.add id s)
-            V.AbstractionId.Set.empty abs_ids
+            (fun s id -> AbstractionId.Set.add id s)
+            AbstractionId.Set.empty abs_ids
         in
         (* End the abstractions and continue *)
         end_abstractions_aux config chain abs_ids cf ctx
@@ -1426,7 +1411,7 @@ and end_proj_loans_symbolic (config : C.config) (chain : borrow_or_abs_ids)
         *)
         (* End the projector of borrows - TODO: not completely sure what to
          * replace it with... Maybe we should introduce an ABottomProj? *)
-        let ctx = update_aproj_borrows abs_id sv V.AIgnoredProjBorrows ctx in
+        let ctx = update_aproj_borrows abs_id sv AIgnoredProjBorrows ctx in
         (* Sanity check: no other occurrence of an intersecting projector of borrows *)
         assert (
           Option.is_none
@@ -1449,9 +1434,9 @@ and end_proj_loans_symbolic (config : C.config) (chain : borrow_or_abs_ids)
         (* Continue *)
         cc cf ctx
 
-let end_borrow config : V.BorrowId.id -> cm_fun = end_borrow_aux config [] None
+let end_borrow config : BorrowId.id -> cm_fun = end_borrow_aux config [] None
 
-let end_borrows config : V.BorrowId.Set.t -> cm_fun =
+let end_borrows config : BorrowId.Set.t -> cm_fun =
   end_borrows_aux config [] None
 
 let end_abstraction config = end_abstraction_aux config []
@@ -1478,20 +1463,20 @@ let end_abstractions_no_synth config ids ctx =
 
     The returned value (previously shared) is checked:
     - it mustn't contain loans
-    - it mustn't contain {!V.Bottom}
+    - it mustn't contain {!Bottom}
     - it mustn't contain reserved borrows
     TODO: this kind of checks should be put in an auxiliary helper, because
     they are redundant.
 
     The loan to update mustn't be a borrowed value.
  *)
-let promote_shared_loan_to_mut_loan (l : V.BorrowId.id)
-    (cf : V.typed_value -> m_fun) : m_fun =
+let promote_shared_loan_to_mut_loan (l : BorrowId.id)
+    (cf : typed_value -> m_fun) : m_fun =
  fun ctx ->
   (* Debug *)
   log#ldebug
     (lazy
-      ("promote_shared_loan_to_mut_loan:\n- loan: " ^ V.BorrowId.to_string l
+      ("promote_shared_loan_to_mut_loan:\n- loan: " ^ BorrowId.to_string l
      ^ "\n- context:\n" ^ eval_ctx_to_string ctx ^ "\n"));
   (* Lookup the shared loan - note that we can't promote a shared loan
    * in a shared value, but we can do it in a mutably borrowed value.
@@ -1501,11 +1486,11 @@ let promote_shared_loan_to_mut_loan (l : V.BorrowId.id)
     { enter_shared_loans = false; enter_mut_borrows = true; enter_abs = false }
   in
   match lookup_loan ek l ctx with
-  | _, Concrete (V.MutLoan _) ->
+  | _, Concrete (VMutLoan _) ->
       raise (Failure "Expected a shared loan, found a mut loan")
-  | _, Concrete (V.SharedLoan (bids, sv)) ->
+  | _, Concrete (VSharedLoan (bids, sv)) ->
       (* Check that there is only one borrow id (l) and update the loan *)
-      assert (V.BorrowId.Set.mem l bids && V.BorrowId.Set.cardinal bids = 1);
+      assert (BorrowId.Set.mem l bids && BorrowId.Set.cardinal bids = 1);
       (* We need to check that there aren't any loans in the value:
          we should have gotten rid of those already, but it is better
          to do a sanity check. *)
@@ -1515,7 +1500,7 @@ let promote_shared_loan_to_mut_loan (l : V.BorrowId.id)
       (* Check there aren't reserved borrows *)
       assert (not (reserved_in_value sv));
       (* Update the loan content *)
-      let ctx = update_loan ek l (V.MutLoan l) ctx in
+      let ctx = update_loan ek l (VMutLoan l) ctx in
       (* Continue *)
       cf sv ctx
   | _, Abstract _ ->
@@ -1531,8 +1516,8 @@ let promote_shared_loan_to_mut_loan (l : V.BorrowId.id)
     This function updates a shared borrow to a mutable borrow (and that is
     all: it doesn't touch the corresponding loan).
  *)
-let replace_reserved_borrow_with_mut_borrow (l : V.BorrowId.id) (cf : m_fun)
-    (borrowed_value : V.typed_value) : m_fun =
+let replace_reserved_borrow_with_mut_borrow (l : BorrowId.id) (cf : m_fun)
+    (borrowed_value : typed_value) : m_fun =
  fun ctx ->
   (* Lookup the reserved borrow - note that we don't go inside borrows/loans:
      there can't be reserved borrows inside other borrows/loans
@@ -1542,11 +1527,11 @@ let replace_reserved_borrow_with_mut_borrow (l : V.BorrowId.id) (cf : m_fun)
   in
   let ctx =
     match lookup_borrow ek l ctx with
-    | Concrete (V.SharedBorrow _ | V.MutBorrow (_, _)) ->
+    | Concrete (VSharedBorrow _ | VMutBorrow (_, _)) ->
         raise (Failure "Expected a reserved mutable borrow")
-    | Concrete (V.ReservedMutBorrow _) ->
+    | Concrete (VReservedMutBorrow _) ->
         (* Update it *)
-        update_borrow ek l (V.MutBorrow (l, borrowed_value)) ctx
+        update_borrow ek l (VMutBorrow (l, borrowed_value)) ctx
     | Abstract _ ->
         (* This can't happen for sure *)
         raise
@@ -1558,16 +1543,16 @@ let replace_reserved_borrow_with_mut_borrow (l : V.BorrowId.id) (cf : m_fun)
   cf ctx
 
 (** Promote a reserved mut borrow to a mut borrow. *)
-let rec promote_reserved_mut_borrow (config : C.config) (l : V.BorrowId.id) :
-    cm_fun =
+let rec promote_reserved_mut_borrow (config : config) (l : BorrowId.id) : cm_fun
+    =
  fun cf ctx ->
   (* Lookup the value *)
   let ek =
     { enter_shared_loans = false; enter_mut_borrows = true; enter_abs = false }
   in
   match lookup_loan ek l ctx with
-  | _, Concrete (V.MutLoan _) -> raise (Failure "Unreachable")
-  | _, Concrete (V.SharedLoan (bids, sv)) -> (
+  | _, Concrete (VMutLoan _) -> raise (Failure "Unreachable")
+  | _, Concrete (VSharedLoan (bids, sv)) -> (
       (* If there are loans inside the value, end them. Note that there can't be
          reserved borrows inside the value.
          If we perform an update, do a recursive call to lookup the updated value *)
@@ -1576,8 +1561,8 @@ let rec promote_reserved_mut_borrow (config : C.config) (l : V.BorrowId.id) :
           (* End the loans *)
           let cc =
             match lc with
-            | V.SharedLoan (bids, _) -> end_borrows config bids
-            | V.MutLoan bid -> end_borrow config bid
+            | VSharedLoan (bids, _) -> end_borrows config bids
+            | VMutLoan bid -> end_borrow config bid
           in
           (* Recursive call *)
           let cc = comp cc (promote_reserved_mut_borrow config l) in
@@ -1595,7 +1580,7 @@ let rec promote_reserved_mut_borrow (config : C.config) (l : V.BorrowId.id) :
           assert (not (reserved_in_value sv));
           (* End the borrows which borrow from the value, at the exception of
              the borrow we want to promote *)
-          let bids = V.BorrowId.Set.remove l bids in
+          let bids = BorrowId.Set.remove l bids in
           let cc = end_borrows config bids in
           (* Promote the loan - TODO: this will fail if the value contains
            * any loans. In practice, it shouldn't, but we could also
@@ -1619,9 +1604,8 @@ let rec promote_reserved_mut_borrow (config : C.config) (l : V.BorrowId.id) :
            "Can't activate a reserved mutable borrow referencing a loan inside\n\
            \         an abstraction")
 
-let destructure_abs (abs_kind : V.abs_kind) (can_end : bool)
-    (destructure_shared_values : bool) (ctx : C.eval_ctx) (abs0 : V.abs) : V.abs
-    =
+let destructure_abs (abs_kind : abs_kind) (can_end : bool)
+    (destructure_shared_values : bool) (ctx : eval_ctx) (abs0 : abs) : abs =
   (* Accumulator to store the destructured values *)
   let avalues = ref [] in
   (* Utility function to store a value in the accumulator *)
@@ -1635,10 +1619,10 @@ let destructure_abs (abs_kind : V.abs_kind) (can_end : bool)
   *)
   let push_fail _ = raise (Failure "Unreachable") in
   (* Function to explore an avalue and destructure it *)
-  let rec list_avalues (allow_borrows : bool) (push : V.typed_avalue -> unit)
-      (av : V.typed_avalue) : unit =
-    let ty = av.V.ty in
-    match av.V.value with
+  let rec list_avalues (allow_borrows : bool) (push : typed_avalue -> unit)
+      (av : typed_avalue) : unit =
+    let ty = av.ty in
+    match av.value with
     | ABottom | AIgnored -> ()
     | AAdt adt ->
         (* Simply explore the children *)
@@ -1646,17 +1630,17 @@ let destructure_abs (abs_kind : V.abs_kind) (can_end : bool)
     | ALoan lc -> (
         (* Explore the loan content *)
         match lc with
-        | V.ASharedLoan (bids, sv, child_av) ->
+        | ASharedLoan (bids, sv, child_av) ->
             (* We don't support nested borrows for now *)
-            assert (not (value_has_borrows ctx sv.V.value));
+            assert (not (value_has_borrows ctx sv.value));
             (* Destructure the shared value *)
             let avl, sv =
               if destructure_shared_values then list_values sv else ([], sv)
             in
             (* Push a value *)
-            let ignored = mk_aignored child_av.V.ty in
-            let value = V.ALoan (V.ASharedLoan (bids, sv, ignored)) in
-            push { V.value; ty };
+            let ignored = mk_aignored child_av.ty in
+            let value = ALoan (ASharedLoan (bids, sv, ignored)) in
+            push { value; ty };
             (* Explore the child *)
             list_avalues false push_fail child_av;
             (* Push the avalues introduced because we decomposed the inner loans -
@@ -1666,25 +1650,25 @@ let destructure_abs (abs_kind : V.abs_kind) (can_end : bool)
                exactly the same way as [list_avalues] (i.e., with a similar
                signature) *)
             List.iter push avl
-        | V.AMutLoan (bid, child_av) ->
+        | AMutLoan (bid, child_av) ->
             (* Explore the child *)
             list_avalues false push_fail child_av;
             (* Explore the whole loan *)
-            let ignored = mk_aignored child_av.V.ty in
-            let value = V.ALoan (V.AMutLoan (bid, ignored)) in
-            push { V.value; ty }
-        | V.AIgnoredMutLoan (opt_bid, child_av) ->
+            let ignored = mk_aignored child_av.ty in
+            let value = ALoan (AMutLoan (bid, ignored)) in
+            push { value; ty }
+        | AIgnoredMutLoan (opt_bid, child_av) ->
             (* We don't support nested borrows for now *)
             assert (not (ty_has_borrows ctx.type_context.type_infos child_av.ty));
             assert (opt_bid = None);
             (* Simply explore the child *)
             list_avalues false push_fail child_av
-        | V.AEndedMutLoan
+        | AEndedMutLoan
             { child = child_av; given_back = _; given_back_meta = _ }
-        | V.AEndedSharedLoan (_, child_av)
-        | V.AEndedIgnoredMutLoan
+        | AEndedSharedLoan (_, child_av)
+        | AEndedIgnoredMutLoan
             { child = child_av; given_back = _; given_back_meta = _ }
-        | V.AIgnoredSharedLoan child_av ->
+        | AIgnoredSharedLoan child_av ->
             (* We don't support nested borrows for now *)
             assert (not (ty_has_borrows ctx.type_context.type_infos child_av.ty));
             (* Simply explore the child *)
@@ -1694,34 +1678,34 @@ let destructure_abs (abs_kind : V.abs_kind) (can_end : bool)
         assert allow_borrows;
         (* Explore the borrow content *)
         match bc with
-        | V.AMutBorrow (bid, child_av) ->
+        | AMutBorrow (bid, child_av) ->
             (* Explore the child *)
             list_avalues false push_fail child_av;
             (* Explore the borrow *)
-            let ignored = mk_aignored child_av.V.ty in
-            let value = V.ABorrow (V.AMutBorrow (bid, ignored)) in
-            push { V.value; ty }
-        | V.ASharedBorrow _ ->
+            let ignored = mk_aignored child_av.ty in
+            let value = ABorrow (AMutBorrow (bid, ignored)) in
+            push { value; ty }
+        | ASharedBorrow _ ->
             (* Nothing specific to do: keep the value as it is *)
             push av
-        | V.AIgnoredMutBorrow (opt_bid, child_av) ->
+        | AIgnoredMutBorrow (opt_bid, child_av) ->
             (* We don't support nested borrows for now *)
             assert (not (ty_has_borrows ctx.type_context.type_infos child_av.ty));
             assert (opt_bid = None);
             (* Just explore the child *)
             list_avalues false push_fail child_av
-        | V.AEndedIgnoredMutBorrow
+        | AEndedIgnoredMutBorrow
             { child = child_av; given_back = _; given_back_meta = _ } ->
             (* We don't support nested borrows for now *)
             assert (not (ty_has_borrows ctx.type_context.type_infos child_av.ty));
             (* Just explore the child *)
             list_avalues false push_fail child_av
-        | V.AProjSharedBorrow asb ->
+        | AProjSharedBorrow asb ->
             (* We don't support nested borrows *)
             assert (asb = []);
             (* Nothing specific to do *)
             ()
-        | V.AEndedMutBorrow _ | V.AEndedSharedBorrow ->
+        | AEndedMutBorrow _ | AEndedSharedBorrow ->
             (* If we get there it means the abstraction ended: it should not
                be in the context anymore (if we end *one* borrow in an abstraction,
                we have to end them all and remove the abstraction from the context)
@@ -1731,55 +1715,52 @@ let destructure_abs (abs_kind : V.abs_kind) (can_end : bool)
         (* For now, we fore all symbolic values containing borrows to be eagerly
            expanded *)
         assert (not (ty_has_borrows ctx.type_context.type_infos ty))
-  and list_values (v : V.typed_value) : V.typed_avalue list * V.typed_value =
-    let ty = v.V.ty in
-    match v.V.value with
-    | Literal _ -> ([], v)
-    | Adt adt ->
+  and list_values (v : typed_value) : typed_avalue list * typed_value =
+    let ty = v.ty in
+    match v.value with
+    | VLiteral _ -> ([], v)
+    | VAdt adt ->
         let avll, field_values =
           List.split (List.map list_values adt.field_values)
         in
         let avl = List.concat avll in
-        let adt = { adt with V.field_values } in
-        (avl, { v with V.value = Adt adt })
-    | Bottom -> raise (Failure "Unreachable")
-    | Borrow _ ->
+        let adt = { adt with field_values } in
+        (avl, { v with value = VAdt adt })
+    | VBottom -> raise (Failure "Unreachable")
+    | VBorrow _ ->
         (* We don't support nested borrows for now *)
         raise (Failure "Unreachable")
-    | Loan lc -> (
+    | VLoan lc -> (
         match lc with
-        | SharedLoan (bids, sv) ->
+        | VSharedLoan (bids, sv) ->
             let avl, sv = list_values sv in
-            if destructure_shared_values then
+            if destructure_shared_values then (
               (* Rem.: the shared value can't contain loans nor borrows *)
-              let rty = ety_no_regions_to_rty ty in
-              let av : V.typed_avalue =
-                assert (not (value_has_loans_or_borrows ctx sv.V.value));
+              assert (ty_no_regions ty);
+              let av : typed_avalue =
+                assert (not (value_has_loans_or_borrows ctx sv.value));
                 (* We introduce fresh ids for the symbolic values *)
-                let mk_value_with_fresh_sids (v : V.typed_value) : V.typed_value
-                    =
+                let mk_value_with_fresh_sids (v : typed_value) : typed_value =
                   let visitor =
                     object
-                      inherit [_] V.map_typed_avalue
+                      inherit [_] map_typed_avalue
 
                       method! visit_symbolic_value_id _ _ =
-                        C.fresh_symbolic_value_id ()
+                        fresh_symbolic_value_id ()
                     end
                   in
                   visitor#visit_typed_value () v
                 in
                 let sv = mk_value_with_fresh_sids sv in
                 (* Create the new avalue *)
-                let value =
-                  V.ALoan (V.ASharedLoan (bids, sv, mk_aignored rty))
-                in
-                { V.value; ty = rty }
+                let value = ALoan (ASharedLoan (bids, sv, mk_aignored ty)) in
+                { value; ty }
               in
               let avl = List.append [ av ] avl in
-              (avl, sv)
-            else (avl, { v with V.value = V.Loan (V.SharedLoan (bids, sv)) })
-        | MutLoan _ -> raise (Failure "Unreachable"))
-    | Symbolic _ ->
+              (avl, sv))
+            else (avl, { v with value = VLoan (VSharedLoan (bids, sv)) })
+        | VMutLoan _ -> raise (Failure "Unreachable"))
+    | VSymbolic _ ->
         (* For now, we fore all symbolic values containing borrows to be eagerly
            expanded *)
         assert (not (ty_has_borrows ctx.type_context.type_infos ty));
@@ -1787,37 +1768,37 @@ let destructure_abs (abs_kind : V.abs_kind) (can_end : bool)
   in
 
   (* Destructure the avalues *)
-  List.iter (list_avalues true push_avalue) abs0.V.avalues;
+  List.iter (list_avalues true push_avalue) abs0.avalues;
   let avalues = !avalues in
   (* Update *)
-  { abs0 with V.avalues; kind = abs_kind; can_end }
+  { abs0 with avalues; kind = abs_kind; can_end }
 
-let abs_is_destructured (destructure_shared_values : bool) (ctx : C.eval_ctx)
-    (abs : V.abs) : bool =
+let abs_is_destructured (destructure_shared_values : bool) (ctx : eval_ctx)
+    (abs : abs) : bool =
   let abs' =
     destructure_abs abs.kind abs.can_end destructure_shared_values ctx abs
   in
   abs = abs'
 
-let convert_value_to_abstractions (abs_kind : V.abs_kind) (can_end : bool)
-    (destructure_shared_values : bool) (ctx : C.eval_ctx) (v : V.typed_value) :
-    V.abs list =
+let convert_value_to_abstractions (abs_kind : abs_kind) (can_end : bool)
+    (destructure_shared_values : bool) (ctx : eval_ctx) (v : typed_value) :
+    abs list =
   (* Convert the value to a list of avalues *)
   let absl = ref [] in
-  let push_abs (r_id : T.RegionId.id) (avalues : V.typed_avalue list) : unit =
+  let push_abs (r_id : RegionId.id) (avalues : typed_avalue list) : unit =
     if avalues = [] then ()
     else
       (* Create the abs - note that we keep the order of the avalues as it is
          (unlike the environments) *)
       let abs =
         {
-          V.abs_id = C.fresh_abstraction_id ();
+          abs_id = fresh_abstraction_id ();
           kind = abs_kind;
           can_end;
-          parents = V.AbstractionId.Set.empty;
+          parents = AbstractionId.Set.empty;
           original_parents = [];
-          regions = T.RegionId.Set.singleton r_id;
-          ancestors_regions = T.RegionId.Set.empty;
+          regions = RegionId.Set.singleton r_id;
+          ancestors_regions = RegionId.Set.empty;
           avalues;
         }
       in
@@ -1832,22 +1813,22 @@ let convert_value_to_abstractions (abs_kind : V.abs_kind) (can_end : bool)
      is [true], this shared value will be stripped of its shared loans.
   *)
   let rec to_avalues (allow_borrows : bool) (inside_borrowed : bool)
-      (group : bool) (r_id : T.RegionId.id) (v : V.typed_value) :
-      V.typed_avalue list * V.typed_value =
+      (group : bool) (r_id : RegionId.id) (v : typed_value) :
+      typed_avalue list * typed_value =
     (* Debug *)
     log#ldebug
       (lazy
         ("convert_value_to_abstractions: to_avalues:\n- value: "
         ^ typed_value_to_string ctx v));
 
-    let ty = v.V.ty in
-    match v.V.value with
-    | V.Literal _ -> ([], v)
-    | V.Bottom ->
+    let ty = v.ty in
+    match v.value with
+    | VLiteral _ -> ([], v)
+    | VBottom ->
         (* Can happen: we *do* convert dummy values to abstractions, and dummy
            values can contain bottoms *)
         ([], v)
-    | V.Adt adt ->
+    | VAdt adt ->
         (* Two cases, depending on whether we have to group all the borrows/loans
            inside one abstraction or not *)
         let avl, field_values =
@@ -1865,7 +1846,7 @@ let convert_value_to_abstractions (abs_kind : V.abs_kind) (can_end : bool)
             let field_values =
               List.map
                 (fun fv ->
-                  let r_id = C.fresh_region_id () in
+                  let r_id = fresh_region_id () in
                   let avl, fv =
                     to_avalues allow_borrows inside_borrowed group r_id fv
                   in
@@ -1879,98 +1860,98 @@ let convert_value_to_abstractions (abs_kind : V.abs_kind) (can_end : bool)
             ([], field_values)
         in
         let adt = { adt with field_values } in
-        (avl, { v with V.value = V.Adt adt })
-    | V.Borrow bc -> (
+        (avl, { v with value = VAdt adt })
+    | VBorrow bc -> (
         let _, ref_ty, kind = ty_as_ref ty in
+        assert (ty_no_regions ref_ty);
         (* Sanity check *)
         assert allow_borrows;
         (* Convert the borrow content *)
         match bc with
-        | SharedBorrow bid ->
-            let ref_ty = ety_no_regions_to_rty ref_ty in
-            let ty = T.Ref (T.Var r_id, ref_ty, kind) in
-            let value = V.ABorrow (V.ASharedBorrow bid) in
-            ([ { V.value; ty } ], v)
-        | MutBorrow (bid, bv) ->
-            let r_id = if group then r_id else C.fresh_region_id () in
+        | VSharedBorrow bid ->
+            assert (ty_no_regions ref_ty);
+            let ty = TRef (RVar r_id, ref_ty, kind) in
+            let value = ABorrow (ASharedBorrow bid) in
+            ([ { value; ty } ], v)
+        | VMutBorrow (bid, bv) ->
+            let r_id = if group then r_id else fresh_region_id () in
             (* We don't support nested borrows for now *)
-            assert (not (value_has_borrows ctx bv.V.value));
+            assert (not (value_has_borrows ctx bv.value));
             (* Create an avalue to push - note that we use [AIgnore] for the inner avalue *)
-            let ref_ty = ety_no_regions_to_rty ref_ty in
-            let ty = T.Ref (T.Var r_id, ref_ty, kind) in
+            let ty = TRef (RVar r_id, ref_ty, kind) in
             let ignored = mk_aignored ref_ty in
-            let av = V.ABorrow (V.AMutBorrow (bid, ignored)) in
-            let av = { V.value = av; ty } in
+            let av = ABorrow (AMutBorrow (bid, ignored)) in
+            let av = { value = av; ty } in
             (* Continue exploring, looking for loans (and forbidding borrows,
                because we don't support nested borrows for now) *)
             let avl, bv = to_avalues false true true r_id bv in
-            let value = { v with V.value = V.Borrow (V.MutBorrow (bid, bv)) } in
+            let value = { v with value = VBorrow (VMutBorrow (bid, bv)) } in
             (av :: avl, value)
-        | ReservedMutBorrow _ ->
+        | VReservedMutBorrow _ ->
             (* This borrow should have been activated *)
             raise (Failure "Unexpected"))
-    | V.Loan lc -> (
+    | VLoan lc -> (
         match lc with
-        | V.SharedLoan (bids, sv) ->
-            let r_id = if group then r_id else C.fresh_region_id () in
+        | VSharedLoan (bids, sv) ->
+            let r_id = if group then r_id else fresh_region_id () in
             (* We don't support nested borrows for now *)
-            assert (not (value_has_borrows ctx sv.V.value));
+            assert (not (value_has_borrows ctx sv.value));
             (* Push the avalue - note that we use [AIgnore] for the inner avalue *)
             (* For avalues, a loan has the borrow type *)
-            let ty = ety_no_regions_to_rty ty in
-            let ty = mk_ref_ty (T.Var r_id) ty T.Shared in
+            assert (ty_no_regions ty);
+            let ty = mk_ref_ty (RVar r_id) ty RShared in
             let ignored = mk_aignored ty in
             (* Rem.: the shared value might contain loans *)
             let avl, sv = to_avalues false true true r_id sv in
-            let av = V.ALoan (V.ASharedLoan (bids, sv, ignored)) in
-            let av = { V.value = av; ty } in
+            let av = ALoan (ASharedLoan (bids, sv, ignored)) in
+            let av = { value = av; ty } in
             (* Continue exploring, looking for loans (and forbidding borrows,
                because we don't support nested borrows for now) *)
-            let value : V.value =
-              if destructure_shared_values then sv.V.value
-              else V.Loan (V.SharedLoan (bids, sv))
+            let value : value =
+              if destructure_shared_values then sv.value
+              else VLoan (VSharedLoan (bids, sv))
             in
-            let value = { v with V.value } in
+            let value = { v with value } in
             (av :: avl, value)
-        | V.MutLoan bid ->
+        | VMutLoan bid ->
             (* Push the avalue - note that we use [AIgnore] for the inner avalue *)
             (* For avalues, a loan has the borrow type *)
-            let ty = ety_no_regions_to_rty ty in
-            let ty = mk_ref_ty (T.Var r_id) ty T.Mut in
+            assert (ty_no_regions ty);
+            let ty = mk_ref_ty (RVar r_id) ty RMut in
             let ignored = mk_aignored ty in
-            let av = V.ALoan (V.AMutLoan (bid, ignored)) in
-            let av = { V.value = av; ty } in
+            let av = ALoan (AMutLoan (bid, ignored)) in
+            let av = { value = av; ty } in
             ([ av ], v))
-    | V.Symbolic _ ->
+    | VSymbolic _ ->
         (* For now, we force all the symbolic values containing borrows to
            be eagerly expanded, and we don't support nested borrows *)
-        assert (not (value_has_borrows ctx v.V.value));
+        assert (not (value_has_borrows ctx v.value));
         (* Return nothing *)
         ([], v)
   in
   (* Generate the avalues *)
-  let r_id = C.fresh_region_id () in
+  let r_id = fresh_region_id () in
   let values, _ = to_avalues true false false r_id v in
   (* Introduce an abstraction for the returned values *)
   push_abs r_id values;
   (* Return *)
   List.rev !absl
 
-type borrow_or_loan_id = BorrowId of V.borrow_id | LoanId of V.loan_id
+type borrow_or_loan_id = BorrowId of borrow_id | LoanId of loan_id
 
 type g_loan_content_with_ty =
-  (T.ety * V.loan_content, T.rty * V.aloan_content) concrete_or_abs
+  (ety * loan_content, rty * aloan_content) concrete_or_abs
 
 type g_borrow_content_with_ty =
-  (T.ety * V.borrow_content, T.rty * V.aborrow_content) concrete_or_abs
+  (ety * borrow_content, rty * aborrow_content) concrete_or_abs
 
 type merge_abstraction_info = {
-  loans : V.loan_id_set;
-  borrows : V.borrow_id_set;
+  loans : loan_id_set;
+  borrows : borrow_id_set;
   borrows_loans : borrow_or_loan_id list;
       (** We use a list to preserve the order in which the borrows were found *)
-  loan_to_content : g_loan_content_with_ty V.BorrowId.Map.t;
-  borrow_to_content : g_borrow_content_with_ty V.BorrowId.Map.t;
+  loan_to_content : g_loan_content_with_ty BorrowId.Map.t;
+  borrow_to_content : g_borrow_content_with_ty BorrowId.Map.t;
 }
 
 (** Small utility to help merging abstractions.
@@ -1985,54 +1966,54 @@ type merge_abstraction_info = {
     - all the borrows are destructured (for instance, shared loans can't
       contain shared loans).
  *)
-let compute_merge_abstraction_info (ctx : C.eval_ctx) (abs : V.abs) :
+let compute_merge_abstraction_info (ctx : eval_ctx) (abs : abs) :
     merge_abstraction_info =
-  let loans : V.loan_id_set ref = ref V.BorrowId.Set.empty in
-  let borrows : V.borrow_id_set ref = ref V.BorrowId.Set.empty in
+  let loans : loan_id_set ref = ref BorrowId.Set.empty in
+  let borrows : borrow_id_set ref = ref BorrowId.Set.empty in
   let borrows_loans : borrow_or_loan_id list ref = ref [] in
-  let loan_to_content : g_loan_content_with_ty V.BorrowId.Map.t ref =
-    ref V.BorrowId.Map.empty
+  let loan_to_content : g_loan_content_with_ty BorrowId.Map.t ref =
+    ref BorrowId.Map.empty
   in
-  let borrow_to_content : g_borrow_content_with_ty V.BorrowId.Map.t ref =
-    ref V.BorrowId.Map.empty
+  let borrow_to_content : g_borrow_content_with_ty BorrowId.Map.t ref =
+    ref BorrowId.Map.empty
   in
 
   let push_loans ids (lc : g_loan_content_with_ty) : unit =
-    assert (V.BorrowId.Set.disjoint !loans ids);
-    loans := V.BorrowId.Set.union !loans ids;
-    V.BorrowId.Set.iter
+    assert (BorrowId.Set.disjoint !loans ids);
+    loans := BorrowId.Set.union !loans ids;
+    BorrowId.Set.iter
       (fun id ->
-        assert (not (V.BorrowId.Map.mem id !loan_to_content));
-        loan_to_content := V.BorrowId.Map.add id lc !loan_to_content;
+        assert (not (BorrowId.Map.mem id !loan_to_content));
+        loan_to_content := BorrowId.Map.add id lc !loan_to_content;
         borrows_loans := LoanId id :: !borrows_loans)
       ids
   in
   let push_loan id (lc : g_loan_content_with_ty) : unit =
-    assert (not (V.BorrowId.Set.mem id !loans));
-    loans := V.BorrowId.Set.add id !loans;
-    assert (not (V.BorrowId.Map.mem id !loan_to_content));
-    loan_to_content := V.BorrowId.Map.add id lc !loan_to_content;
+    assert (not (BorrowId.Set.mem id !loans));
+    loans := BorrowId.Set.add id !loans;
+    assert (not (BorrowId.Map.mem id !loan_to_content));
+    loan_to_content := BorrowId.Map.add id lc !loan_to_content;
     borrows_loans := LoanId id :: !borrows_loans
   in
   let push_borrow id (bc : g_borrow_content_with_ty) : unit =
-    assert (not (V.BorrowId.Set.mem id !borrows));
-    borrows := V.BorrowId.Set.add id !borrows;
-    assert (not (V.BorrowId.Map.mem id !borrow_to_content));
-    borrow_to_content := V.BorrowId.Map.add id bc !borrow_to_content;
+    assert (not (BorrowId.Set.mem id !borrows));
+    borrows := BorrowId.Set.add id !borrows;
+    assert (not (BorrowId.Map.mem id !borrow_to_content));
+    borrow_to_content := BorrowId.Map.add id bc !borrow_to_content;
     borrows_loans := BorrowId id :: !borrows_loans
   in
 
   let iter_avalues =
     object
-      inherit [_] V.iter_typed_avalue as super
+      inherit [_] iter_typed_avalue as super
 
       (** We redefine this to track the types *)
       method! visit_typed_avalue _ v =
-        super#visit_typed_avalue (Some (Abstract v.V.ty)) v
+        super#visit_typed_avalue (Some (Abstract v.ty)) v
 
       (** We redefine this to track the types *)
-      method! visit_typed_value _ (v : V.typed_value) =
-        super#visit_typed_value (Some (Concrete v.V.ty)) v
+      method! visit_typed_value _ (v : typed_value) =
+        super#visit_typed_value (Some (Concrete v.ty)) v
 
       method! visit_loan_content env lc =
         (* Can happen if we explore shared values whose sub-values are
@@ -2043,8 +2024,8 @@ let compute_merge_abstraction_info (ctx : C.eval_ctx) (abs : V.abs) :
           | Abstract _ -> raise (Failure "Unreachable")
         in
         (match lc with
-        | SharedLoan (bids, _) -> push_loans bids (Concrete (ty, lc))
-        | MutLoan _ -> raise (Failure "Unreachable"));
+        | VSharedLoan (bids, _) -> push_loans bids (Concrete (ty, lc))
+        | VMutLoan _ -> raise (Failure "Unreachable"));
         (* Continue *)
         super#visit_loan_content env lc
 
@@ -2061,10 +2042,10 @@ let compute_merge_abstraction_info (ctx : C.eval_ctx) (abs : V.abs) :
         in
         (* Register the loans *)
         (match lc with
-        | V.ASharedLoan (bids, _, _) -> push_loans bids (Abstract (ty, lc))
-        | V.AMutLoan (bid, _) -> push_loan bid (Abstract (ty, lc))
-        | V.AEndedMutLoan _ | V.AEndedSharedLoan _ | V.AIgnoredMutLoan _
-        | V.AEndedIgnoredMutLoan _ | V.AIgnoredSharedLoan _ ->
+        | ASharedLoan (bids, _, _) -> push_loans bids (Abstract (ty, lc))
+        | AMutLoan (bid, _) -> push_loan bid (Abstract (ty, lc))
+        | AEndedMutLoan _ | AEndedSharedLoan _ | AIgnoredMutLoan _
+        | AEndedIgnoredMutLoan _ | AIgnoredSharedLoan _ ->
             (* The abstraction has been destructured, so those shouldn't appear *)
             raise (Failure "Unreachable"));
         (* Continue *)
@@ -2078,20 +2059,20 @@ let compute_merge_abstraction_info (ctx : C.eval_ctx) (abs : V.abs) :
         in
         (* Explore the borrow content *)
         (match bc with
-        | V.AMutBorrow (bid, _) -> push_borrow bid (Abstract (ty, bc))
-        | V.ASharedBorrow bid -> push_borrow bid (Abstract (ty, bc))
-        | V.AProjSharedBorrow asb ->
+        | AMutBorrow (bid, _) -> push_borrow bid (Abstract (ty, bc))
+        | ASharedBorrow bid -> push_borrow bid (Abstract (ty, bc))
+        | AProjSharedBorrow asb ->
             let register asb =
               match asb with
-              | V.AsbBorrow bid -> push_borrow bid (Abstract (ty, bc))
-              | V.AsbProjReborrows _ ->
+              | AsbBorrow bid -> push_borrow bid (Abstract (ty, bc))
+              | AsbProjReborrows _ ->
                   (* Can only happen if the symbolic value (potentially) contains
                      borrows - i.e., we have nested borrows *)
                   raise (Failure "Unreachable")
             in
             List.iter register asb
-        | V.AIgnoredMutBorrow _ | V.AEndedIgnoredMutBorrow _
-        | V.AEndedMutBorrow _ | V.AEndedSharedBorrow ->
+        | AIgnoredMutBorrow _ | AEndedIgnoredMutBorrow _ | AEndedMutBorrow _
+        | AEndedSharedBorrow ->
             (* The abstraction has been destructured, so those shouldn't appear *)
             raise (Failure "Unreachable"));
         super#visit_aborrow_content env bc
@@ -2102,7 +2083,7 @@ let compute_merge_abstraction_info (ctx : C.eval_ctx) (abs : V.abs) :
     end
   in
 
-  List.iter (iter_avalues#visit_typed_avalue None) abs.V.avalues;
+  List.iter (iter_avalues#visit_typed_avalue None) abs.avalues;
 
   {
     loans = !loans;
@@ -2114,12 +2095,7 @@ let compute_merge_abstraction_info (ctx : C.eval_ctx) (abs : V.abs) :
 
 type merge_duplicates_funcs = {
   merge_amut_borrows :
-    V.borrow_id ->
-    T.rty ->
-    V.typed_avalue ->
-    T.rty ->
-    V.typed_avalue ->
-    V.typed_avalue;
+    borrow_id -> rty -> typed_avalue -> rty -> typed_avalue -> typed_avalue;
       (** Parameters:
           - [id]
           - [ty0]
@@ -2129,19 +2105,14 @@ type merge_duplicates_funcs = {
 
           The children should be [AIgnored].
        *)
-  merge_ashared_borrows : V.borrow_id -> T.rty -> T.rty -> V.typed_avalue;
+  merge_ashared_borrows : borrow_id -> rty -> rty -> typed_avalue;
       (** Parameters:
           - [id]
           - [ty0]
           - [ty1]
        *)
   merge_amut_loans :
-    V.loan_id ->
-    T.rty ->
-    V.typed_avalue ->
-    T.rty ->
-    V.typed_avalue ->
-    V.typed_avalue;
+    loan_id -> rty -> typed_avalue -> rty -> typed_avalue -> typed_avalue;
       (** Parameters:
           - [id]
           - [ty0]
@@ -2152,14 +2123,14 @@ type merge_duplicates_funcs = {
           The children should be [AIgnored].
        *)
   merge_ashared_loans :
-    V.loan_id_set ->
-    T.rty ->
-    V.typed_value ->
-    V.typed_avalue ->
-    T.rty ->
-    V.typed_value ->
-    V.typed_avalue ->
-    V.typed_avalue;
+    loan_id_set ->
+    rty ->
+    typed_value ->
+    typed_avalue ->
+    rty ->
+    typed_value ->
+    typed_avalue ->
+    typed_avalue;
       (** Parameters:
           - [ids]
           - [ty0]
@@ -2175,9 +2146,9 @@ type merge_duplicates_funcs = {
 
     Merge two abstractions into one, without updating the context.
  *)
-let merge_into_abstraction_aux (abs_kind : V.abs_kind) (can_end : bool)
-    (merge_funs : merge_duplicates_funcs option) (ctx : C.eval_ctx)
-    (abs0 : V.abs) (abs1 : V.abs) : V.abs =
+let merge_into_abstraction_aux (abs_kind : abs_kind) (can_end : bool)
+    (merge_funs : merge_duplicates_funcs option) (ctx : eval_ctx) (abs0 : abs)
+    (abs1 : abs) : abs =
   log#ldebug
     (lazy
       ("merge_into_abstraction_aux:\n- abs0:\n" ^ abs_to_string ctx abs0
@@ -2213,8 +2184,8 @@ let merge_into_abstraction_aux (abs_kind : V.abs_kind) (can_end : bool)
   (* Sanity check: there is no loan/borrows which appears in both abstractions,
      unless we allow to merge duplicates *)
   if merge_funs = None then (
-    assert (V.BorrowId.Set.disjoint borrows0 borrows1);
-    assert (V.BorrowId.Set.disjoint loans0 loans1));
+    assert (BorrowId.Set.disjoint borrows0 borrows1);
+    assert (BorrowId.Set.disjoint loans0 loans1));
 
   (* Merge.
      There are several cases:
@@ -2234,8 +2205,8 @@ let merge_into_abstraction_aux (abs_kind : V.abs_kind) (can_end : bool)
      We ignore this case for now: we check that whenever we merge two shared loans,
      then their sets of ids are equal.
   *)
-  let merged_borrows = ref V.BorrowId.Set.empty in
-  let merged_loans = ref V.BorrowId.Set.empty in
+  let merged_borrows = ref BorrowId.Set.empty in
+  let merged_loans = ref BorrowId.Set.empty in
   let avalues = ref [] in
   let push_avalue av =
     log#ldebug
@@ -2249,35 +2220,35 @@ let merge_into_abstraction_aux (abs_kind : V.abs_kind) (can_end : bool)
   in
 
   let intersect =
-    V.BorrowId.Set.union
-      (V.BorrowId.Set.inter loans0 borrows1)
-      (V.BorrowId.Set.inter loans1 borrows0)
+    BorrowId.Set.union
+      (BorrowId.Set.inter loans0 borrows1)
+      (BorrowId.Set.inter loans1 borrows0)
   in
-  let filter_bids (bids : V.BorrowId.Set.t) : V.BorrowId.Set.t =
-    let bids = V.BorrowId.Set.diff bids intersect in
-    assert (not (V.BorrowId.Set.is_empty bids));
+  let filter_bids (bids : BorrowId.Set.t) : BorrowId.Set.t =
+    let bids = BorrowId.Set.diff bids intersect in
+    assert (not (BorrowId.Set.is_empty bids));
     bids
   in
-  let filter_bid (bid : V.BorrowId.id) : V.BorrowId.id option =
-    if V.BorrowId.Set.mem bid intersect then None else Some bid
+  let filter_bid (bid : BorrowId.id) : BorrowId.id option =
+    if BorrowId.Set.mem bid intersect then None else Some bid
   in
 
-  let borrow_is_merged id = V.BorrowId.Set.mem id !merged_borrows in
+  let borrow_is_merged id = BorrowId.Set.mem id !merged_borrows in
   let set_borrow_as_merged id =
-    merged_borrows := V.BorrowId.Set.add id !merged_borrows
+    merged_borrows := BorrowId.Set.add id !merged_borrows
   in
-  let loan_is_merged id = V.BorrowId.Set.mem id !merged_loans in
+  let loan_is_merged id = BorrowId.Set.mem id !merged_loans in
   let set_loan_as_merged id =
-    merged_loans := V.BorrowId.Set.add id !merged_loans
+    merged_loans := BorrowId.Set.add id !merged_loans
   in
-  let set_loans_as_merged ids = V.BorrowId.Set.iter set_loan_as_merged ids in
+  let set_loans_as_merged ids = BorrowId.Set.iter set_loan_as_merged ids in
 
   (* Some utility functions *)
   (* Merge two aborrow contents - note that those contents must have the same id *)
-  let merge_aborrow_contents (ty0 : T.rty) (bc0 : V.aborrow_content)
-      (ty1 : T.rty) (bc1 : V.aborrow_content) : V.typed_avalue =
+  let merge_aborrow_contents (ty0 : rty) (bc0 : aborrow_content) (ty1 : rty)
+      (bc1 : aborrow_content) : typed_avalue =
     match (bc0, bc1) with
-    | V.AMutBorrow (id, child0), V.AMutBorrow (_, child1) ->
+    | AMutBorrow (id, child0), AMutBorrow (_, child1) ->
         (Option.get merge_funs).merge_amut_borrows id ty0 child0 ty1 child1
     | ASharedBorrow id, ASharedBorrow _ ->
         (Option.get merge_funs).merge_ashared_borrows id ty0 ty1
@@ -2291,7 +2262,7 @@ let merge_into_abstraction_aux (abs_kind : V.abs_kind) (can_end : bool)
   in
 
   let merge_g_borrow_contents (bc0 : g_borrow_content_with_ty)
-      (bc1 : g_borrow_content_with_ty) : V.typed_avalue =
+      (bc1 : g_borrow_content_with_ty) : typed_avalue =
     match (bc0, bc1) with
     | Concrete _, Concrete _ ->
         (* This can happen only in case of nested borrows *)
@@ -2303,10 +2274,10 @@ let merge_into_abstraction_aux (abs_kind : V.abs_kind) (can_end : bool)
         raise (Failure "Unreachable")
   in
 
-  let merge_aloan_contents (ty0 : T.rty) (lc0 : V.aloan_content) (ty1 : T.rty)
-      (lc1 : V.aloan_content) : V.typed_avalue option =
+  let merge_aloan_contents (ty0 : rty) (lc0 : aloan_content) (ty1 : rty)
+      (lc1 : aloan_content) : typed_avalue option =
     match (lc0, lc1) with
-    | V.AMutLoan (id, child0), V.AMutLoan (_, child1) ->
+    | AMutLoan (id, child0), AMutLoan (_, child1) ->
         (* Register the loan id *)
         set_loan_as_merged id;
         (* Merge *)
@@ -2318,9 +2289,9 @@ let merge_into_abstraction_aux (abs_kind : V.abs_kind) (can_end : bool)
         (* Check that the sets of ids are the same - if it is not the case, it
            means we actually need to merge more than 2 avalues: we ignore this
            case for now *)
-        assert (V.BorrowId.Set.equal ids0 ids1);
+        assert (BorrowId.Set.equal ids0 ids1);
         let ids = ids0 in
-        if V.BorrowId.Set.is_empty ids then (
+        if BorrowId.Set.is_empty ids then (
           (* If the set of ids is empty, we can eliminate this shared loan.
              For now, we check that we can eliminate the whole shared value
              altogether.
@@ -2330,10 +2301,10 @@ let merge_into_abstraction_aux (abs_kind : V.abs_kind) (can_end : bool)
              to preserve (in practice it works because we destructure the
              shared values in the abstractions, and forbid nested borrows).
           *)
-          assert (not (value_has_loans_or_borrows ctx sv0.V.value));
-          assert (not (value_has_loans_or_borrows ctx sv0.V.value));
-          assert (is_aignored child0.V.value);
-          assert (is_aignored child1.V.value);
+          assert (not (value_has_loans_or_borrows ctx sv0.value));
+          assert (not (value_has_loans_or_borrows ctx sv0.value));
+          assert (is_aignored child0.value);
+          assert (is_aignored child1.value);
           None)
         else (
           (* Register the loan ids *)
@@ -2352,7 +2323,7 @@ let merge_into_abstraction_aux (abs_kind : V.abs_kind) (can_end : bool)
      to register the merged loan ids: the caller doesn't do it (contrary to
      the borrow case) *)
   let merge_g_loan_contents (lc0 : g_loan_content_with_ty)
-      (lc1 : g_loan_content_with_ty) : V.typed_avalue option =
+      (lc1 : g_loan_content_with_ty) : typed_avalue option =
     match (lc0, lc1) with
     | Concrete _, Concrete _ ->
         (* This can not happen: the values should have been destructured *)
@@ -2376,7 +2347,7 @@ let merge_into_abstraction_aux (abs_kind : V.abs_kind) (can_end : bool)
           log#ldebug
             (lazy
               ("merge_into_abstraction_aux: merging borrow "
-             ^ V.BorrowId.to_string bid));
+             ^ BorrowId.to_string bid));
 
           (* Check if the borrow has already been merged - this can happen
              because we go through all the borrows/loans in [abs0] *then*
@@ -2390,10 +2361,10 @@ let merge_into_abstraction_aux (abs_kind : V.abs_kind) (can_end : bool)
             | None -> ()
             | Some bid ->
                 (* Lookup the contents *)
-                let bc0 = V.BorrowId.Map.find_opt bid borrow_to_content0 in
-                let bc1 = V.BorrowId.Map.find_opt bid borrow_to_content1 in
+                let bc0 = BorrowId.Map.find_opt bid borrow_to_content0 in
+                let bc1 = BorrowId.Map.find_opt bid borrow_to_content1 in
                 (* Merge *)
-                let av : V.typed_avalue =
+                let av : typed_avalue =
                   match (bc0, bc1) with
                   | None, Some bc | Some bc, None -> (
                       match bc with
@@ -2403,7 +2374,7 @@ let merge_into_abstraction_aux (abs_kind : V.abs_kind) (can_end : bool)
                              loan
                           *)
                           raise (Failure "Unreachable")
-                      | Abstract (ty, bc) -> { V.value = V.ABorrow bc; ty })
+                      | Abstract (ty, bc) -> { value = ABorrow bc; ty })
                   | Some bc0, Some bc1 ->
                       assert (merge_funs <> None);
                       merge_g_borrow_contents bc0 bc1
@@ -2423,17 +2394,17 @@ let merge_into_abstraction_aux (abs_kind : V.abs_kind) (can_end : bool)
             log#ldebug
               (lazy
                 ("merge_into_abstraction_aux: merging loan "
-               ^ V.BorrowId.to_string bid));
+               ^ BorrowId.to_string bid));
 
             (* Check if we need to filter it *)
             match filter_bid bid with
             | None -> ()
             | Some bid ->
                 (* Lookup the contents *)
-                let lc0 = V.BorrowId.Map.find_opt bid loan_to_content0 in
-                let lc1 = V.BorrowId.Map.find_opt bid loan_to_content1 in
+                let lc0 = BorrowId.Map.find_opt bid loan_to_content0 in
+                let lc1 = BorrowId.Map.find_opt bid loan_to_content1 in
                 (* Merge *)
-                let av : V.typed_avalue option =
+                let av : typed_avalue option =
                   match (lc0, lc1) with
                   | None, Some lc | Some lc, None -> (
                       match lc with
@@ -2443,21 +2414,21 @@ let merge_into_abstraction_aux (abs_kind : V.abs_kind) (can_end : bool)
                           raise (Failure "Unreachable")
                       | Abstract (ty, lc) -> (
                           match lc with
-                          | V.ASharedLoan (bids, sv, child) ->
+                          | ASharedLoan (bids, sv, child) ->
                               let bids = filter_bids bids in
-                              assert (not (V.BorrowId.Set.is_empty bids));
-                              assert (is_aignored child.V.value);
+                              assert (not (BorrowId.Set.is_empty bids));
+                              assert (is_aignored child.value);
                               assert (
-                                not (value_has_loans_or_borrows ctx sv.V.value));
-                              let lc = V.ASharedLoan (bids, sv, child) in
+                                not (value_has_loans_or_borrows ctx sv.value));
+                              let lc = ASharedLoan (bids, sv, child) in
                               set_loans_as_merged bids;
-                              Some { V.value = V.ALoan lc; ty }
-                          | V.AMutLoan _ ->
+                              Some { value = ALoan lc; ty }
+                          | AMutLoan _ ->
                               set_loan_as_merged bid;
-                              Some { V.value = V.ALoan lc; ty }
-                          | V.AEndedMutLoan _ | V.AEndedSharedLoan _
-                          | V.AIgnoredMutLoan _ | V.AEndedIgnoredMutLoan _
-                          | V.AIgnoredSharedLoan _ ->
+                              Some { value = ALoan lc; ty }
+                          | AEndedMutLoan _ | AEndedSharedLoan _
+                          | AIgnoredMutLoan _ | AEndedIgnoredMutLoan _
+                          | AIgnoredSharedLoan _ ->
                               (* The abstraction has been destructured, so those shouldn't appear *)
                               raise (Failure "Unreachable")))
                   | Some lc0, Some lc1 ->
@@ -2477,8 +2448,8 @@ let merge_into_abstraction_aux (abs_kind : V.abs_kind) (can_end : bool)
      meaning it is easier to find fixed points).
   *)
   let avalues =
-    let is_borrow (av : V.typed_avalue) : bool =
-      match av.V.value with
+    let is_borrow (av : typed_avalue) : bool =
+      match av.value with
       | ABorrow _ -> true
       | ALoan _ -> false
       | _ -> raise (Failure "Unexpected")
@@ -2490,21 +2461,21 @@ let merge_into_abstraction_aux (abs_kind : V.abs_kind) (can_end : bool)
   (* Filter the regions *)
 
   (* Create the new abstraction *)
-  let abs_id = C.fresh_abstraction_id () in
+  let abs_id = fresh_abstraction_id () in
   (* Note that one of the two abstractions might a parent of the other *)
   let parents =
-    V.AbstractionId.Set.diff
-      (V.AbstractionId.Set.union abs0.parents abs1.parents)
-      (V.AbstractionId.Set.of_list [ abs0.abs_id; abs1.abs_id ])
+    AbstractionId.Set.diff
+      (AbstractionId.Set.union abs0.parents abs1.parents)
+      (AbstractionId.Set.of_list [ abs0.abs_id; abs1.abs_id ])
   in
-  let original_parents = V.AbstractionId.Set.elements parents in
-  let regions = T.RegionId.Set.union abs0.regions abs1.regions in
+  let original_parents = AbstractionId.Set.elements parents in
+  let regions = RegionId.Set.union abs0.regions abs1.regions in
   let ancestors_regions =
-    T.RegionId.Set.diff (T.RegionId.Set.union abs0.regions abs1.regions) regions
+    RegionId.Set.diff (RegionId.Set.union abs0.regions abs1.regions) regions
   in
   let abs =
     {
-      V.abs_id;
+      abs_id;
       kind = abs_kind;
       can_end;
       parents;
@@ -2521,19 +2492,19 @@ let merge_into_abstraction_aux (abs_kind : V.abs_kind) (can_end : bool)
   abs
 
 (** Merge the regions in a context to a single region *)
-let ctx_merge_regions (ctx : C.eval_ctx) (rid : T.RegionId.id)
-    (rids : T.RegionId.Set.t) : C.eval_ctx =
-  let rsubst x = if T.RegionId.Set.mem x rids then rid else x in
+let ctx_merge_regions (ctx : eval_ctx) (rid : RegionId.id)
+    (rids : RegionId.Set.t) : eval_ctx =
+  let rsubst x = if RegionId.Set.mem x rids then rid else x in
   let env = Substitute.env_subst_rids rsubst ctx.env in
-  { ctx with C.env }
+  { ctx with env }
 
-let merge_into_abstraction (abs_kind : V.abs_kind) (can_end : bool)
-    (merge_funs : merge_duplicates_funcs option) (ctx : C.eval_ctx)
-    (abs_id0 : V.AbstractionId.id) (abs_id1 : V.AbstractionId.id) :
-    C.eval_ctx * V.AbstractionId.id =
+let merge_into_abstraction (abs_kind : abs_kind) (can_end : bool)
+    (merge_funs : merge_duplicates_funcs option) (ctx : eval_ctx)
+    (abs_id0 : AbstractionId.id) (abs_id1 : AbstractionId.id) :
+    eval_ctx * AbstractionId.id =
   (* Lookup the abstractions *)
-  let abs0 = C.ctx_lookup_abs ctx abs_id0 in
-  let abs1 = C.ctx_lookup_abs ctx abs_id1 in
+  let abs0 = ctx_lookup_abs ctx abs_id0 in
+  let abs1 = ctx_lookup_abs ctx abs_id1 in
 
   (* Merge them *)
   let nabs =
@@ -2542,8 +2513,8 @@ let merge_into_abstraction (abs_kind : V.abs_kind) (can_end : bool)
 
   (* Update the environment: replace the abstraction 1 with the result of the merge,
      remove the abstraction 0 *)
-  let ctx = fst (C.ctx_subst_abs ctx abs_id1 nabs) in
-  let ctx = fst (C.ctx_remove_abs ctx abs_id0) in
+  let ctx = fst (ctx_subst_abs ctx abs_id1 nabs) in
+  let ctx = fst (ctx_remove_abs ctx abs_id0) in
 
   (* Merge all the regions from the abstraction into one (the first - i.e., the
      one with the smallest id). Note that we need to do this in the whole
@@ -2554,11 +2525,11 @@ let merge_into_abstraction (abs_kind : V.abs_kind) (can_end : bool)
   let ctx =
     let regions = nabs.regions in
     (* Pick the first region id (this is the smallest) *)
-    let rid = T.RegionId.Set.min_elt regions in
+    let rid = RegionId.Set.min_elt regions in
     (* If there is only one region, do nothing *)
-    if T.RegionId.Set.cardinal regions = 1 then ctx
+    if RegionId.Set.cardinal regions = 1 then ctx
     else
-      let rids = T.RegionId.Set.remove rid regions in
+      let rids = RegionId.Set.remove rid regions in
       ctx_merge_regions ctx rid rids
   in
 
diff --git a/compiler/InterpreterBorrows.mli b/compiler/InterpreterBorrows.mli
index 31b67bd7..e47ba82d 100644
--- a/compiler/InterpreterBorrows.mli
+++ b/compiler/InterpreterBorrows.mli
@@ -1,49 +1,44 @@
-module T = Types
-module V = Values
-module C = Contexts
-module Subst = Substitute
-module L = Logging
-module S = SynthesizeSymbolic
+open Types
+open Values
+open Contexts
 open Cps
-open InterpreterProjectors
 
 (** When copying values, we duplicate the shared borrows. This is tantamount to
     reborrowing the shared value. The [reborrow_shared original_id new_bid ctx]
     applies this change to an environment [ctx] by inserting a new borrow id in
     the set of borrows tracked by a shared value, referenced by the
     [original_bid] argument.  *)
-val reborrow_shared : V.BorrowId.id -> V.BorrowId.id -> C.eval_ctx -> C.eval_ctx
+val reborrow_shared : BorrowId.id -> BorrowId.id -> eval_ctx -> eval_ctx
 
 (** End a borrow identified by its id, while preserving the invariants.
 
     If the borrow is inside another borrow/an abstraction or contains loans,
     [end_borrow] will end those borrows/abstractions/loans first.
   *)
-val end_borrow : C.config -> V.BorrowId.id -> cm_fun
+val end_borrow : config -> BorrowId.id -> cm_fun
 
 (** End a set of borrows identified by their ids, while preserving the invariants. *)
-val end_borrows : C.config -> V.BorrowId.Set.t -> cm_fun
+val end_borrows : config -> BorrowId.Set.t -> cm_fun
 
 (** End an abstraction while preserving the invariants. *)
-val end_abstraction : C.config -> V.AbstractionId.id -> cm_fun
+val end_abstraction : config -> AbstractionId.id -> cm_fun
 
 (** End a set of abstractions while preserving the invariants. *)
-val end_abstractions : C.config -> V.AbstractionId.Set.t -> cm_fun
+val end_abstractions : config -> AbstractionId.Set.t -> cm_fun
 
 (** End a borrow and return the resulting environment, ignoring synthesis *)
-val end_borrow_no_synth : C.config -> V.BorrowId.id -> C.eval_ctx -> C.eval_ctx
+val end_borrow_no_synth : config -> BorrowId.id -> eval_ctx -> eval_ctx
 
 (** End a set of borrows and return the resulting environment, ignoring synthesis *)
-val end_borrows_no_synth :
-  C.config -> V.BorrowId.Set.t -> C.eval_ctx -> C.eval_ctx
+val end_borrows_no_synth : config -> BorrowId.Set.t -> eval_ctx -> eval_ctx
 
 (** End an abstraction and return the resulting environment, ignoring synthesis *)
 val end_abstraction_no_synth :
-  C.config -> V.AbstractionId.id -> C.eval_ctx -> C.eval_ctx
+  config -> AbstractionId.id -> eval_ctx -> eval_ctx
 
 (** End a set of abstractions and return the resulting environment, ignoring synthesis *)
 val end_abstractions_no_synth :
-  C.config -> V.AbstractionId.Set.t -> C.eval_ctx -> C.eval_ctx
+  config -> AbstractionId.Set.t -> eval_ctx -> eval_ctx
 
 (** Promote a reserved mut borrow to a mut borrow, while preserving the invariants.
 
@@ -54,7 +49,7 @@ val end_abstractions_no_synth :
     the corresponding shared loan with a mutable loan (after having ended the
     other shared borrows which point to this loan).
  *)
-val promote_reserved_mut_borrow : C.config -> V.BorrowId.id -> cm_fun
+val promote_reserved_mut_borrow : config -> BorrowId.id -> cm_fun
 
 (** Transform an abstraction to an abstraction where the values are not
     structured.
@@ -96,7 +91,7 @@ val promote_reserved_mut_borrow : C.config -> V.BorrowId.id -> cm_fun
     - [ctx]
     - [abs]
  *)
-val destructure_abs : V.abs_kind -> bool -> bool -> C.eval_ctx -> V.abs -> V.abs
+val destructure_abs : abs_kind -> bool -> bool -> eval_ctx -> abs -> abs
 
 (** Return [true] if the values in an abstraction are destructured.
 
@@ -104,7 +99,7 @@ val destructure_abs : V.abs_kind -> bool -> bool -> C.eval_ctx -> V.abs -> V.abs
 
     The input boolean is [destructure_shared_value]. See {!destructure_abs}.
  *)
-val abs_is_destructured : bool -> C.eval_ctx -> V.abs -> bool
+val abs_is_destructured : bool -> eval_ctx -> abs -> bool
 
 (** Turn a value into a abstractions.
 
@@ -130,22 +125,16 @@ val abs_is_destructured : bool -> C.eval_ctx -> V.abs -> bool
     - [v]
  *)
 val convert_value_to_abstractions :
-  V.abs_kind -> bool -> bool -> C.eval_ctx -> V.typed_value -> V.abs list
+  abs_kind -> bool -> bool -> eval_ctx -> typed_value -> abs list
 
 (** See {!merge_into_abstraction}.
 
     Rem.: it may be more idiomatic to have a functor, but this seems a bit
     heavyweight, though.
   *)
-
 type merge_duplicates_funcs = {
   merge_amut_borrows :
-    V.borrow_id ->
-    T.rty ->
-    V.typed_avalue ->
-    T.rty ->
-    V.typed_avalue ->
-    V.typed_avalue;
+    borrow_id -> rty -> typed_avalue -> rty -> typed_avalue -> typed_avalue;
       (** Parameters:
           - [id]
           - [ty0]
@@ -155,19 +144,14 @@ type merge_duplicates_funcs = {
 
           The children should be [AIgnored].
        *)
-  merge_ashared_borrows : V.borrow_id -> T.rty -> T.rty -> V.typed_avalue;
+  merge_ashared_borrows : borrow_id -> rty -> rty -> typed_avalue;
       (** Parameters:
           - [id]
           - [ty0]
           - [ty1]
        *)
   merge_amut_loans :
-    V.loan_id ->
-    T.rty ->
-    V.typed_avalue ->
-    T.rty ->
-    V.typed_avalue ->
-    V.typed_avalue;
+    loan_id -> rty -> typed_avalue -> rty -> typed_avalue -> typed_avalue;
       (** Parameters:
           - [id]
           - [ty0]
@@ -178,14 +162,14 @@ type merge_duplicates_funcs = {
           The children should be [AIgnored].
        *)
   merge_ashared_loans :
-    V.loan_id_set ->
-    T.rty ->
-    V.typed_value ->
-    V.typed_avalue ->
-    T.rty ->
-    V.typed_value ->
-    V.typed_avalue ->
-    V.typed_avalue;
+    loan_id_set ->
+    rty ->
+    typed_value ->
+    typed_avalue ->
+    rty ->
+    typed_value ->
+    typed_avalue ->
+    typed_avalue;
       (** Parameters:
           - [ids]
           - [ty0]
@@ -248,10 +232,10 @@ type merge_duplicates_funcs = {
     results from the merge.
  *)
 val merge_into_abstraction :
-  V.abs_kind ->
+  abs_kind ->
   bool ->
   merge_duplicates_funcs option ->
-  C.eval_ctx ->
-  V.AbstractionId.id ->
-  V.AbstractionId.id ->
-  C.eval_ctx * V.AbstractionId.id
+  eval_ctx ->
+  AbstractionId.id ->
+  AbstractionId.id ->
+  eval_ctx * AbstractionId.id
diff --git a/compiler/InterpreterBorrowsCore.ml b/compiler/InterpreterBorrowsCore.ml
index e7da045c..b13d545c 100644
--- a/compiler/InterpreterBorrowsCore.ml
+++ b/compiler/InterpreterBorrowsCore.ml
@@ -3,17 +3,15 @@
     also in Invariants or InterpreterProjectors
  *)
 
-module T = Types
-module V = Values
-module C = Contexts
-module Subst = Substitute
-module L = Logging
+open Types
+open Values
+open Contexts
 open Utils
 open TypesUtils
 open InterpreterUtils
 
 (** The local logger *)
-let log = L.borrows_log
+let log = Logging.borrows_log
 
 (** TODO: cleanup this a bit, once we have a better understanding about
     what we need.
@@ -33,19 +31,19 @@ type exploration_kind = {
 let ek_all : exploration_kind =
   { enter_shared_loans = true; enter_mut_borrows = true; enter_abs = true }
 
-type borrow_ids = Borrows of V.BorrowId.Set.t | Borrow of V.BorrowId.id
+type borrow_ids = Borrows of BorrowId.Set.t | Borrow of BorrowId.id
 [@@deriving show]
 
 type borrow_ids_or_symbolic_value =
   | BorrowIds of borrow_ids
-  | SymbolicValue of V.symbolic_value
+  | SymbolicValue of symbolic_value
 [@@deriving show]
 
 exception FoundBorrowIds of borrow_ids
 
 type priority_borrows_or_abs =
   | OuterBorrows of borrow_ids
-  | OuterAbs of V.AbstractionId.id
+  | OuterAbs of AbstractionId.id
   | InnerLoans of borrow_ids
 [@@deriving show]
 
@@ -55,20 +53,17 @@ let update_if_none opt x = match opt with None -> Some x | _ -> opt
 exception FoundPriority of priority_borrows_or_abs
 
 type loan_or_borrow_content =
-  | LoanContent of V.loan_content
-  | BorrowContent of V.borrow_content
+  | LoanContent of loan_content
+  | BorrowContent of borrow_content
 [@@deriving show]
 
-type borrow_or_abs_id =
-  | BorrowId of V.BorrowId.id
-  | AbsId of V.AbstractionId.id
-
+type borrow_or_abs_id = BorrowId of BorrowId.id | AbsId of AbstractionId.id
 type borrow_or_abs_ids = borrow_or_abs_id list
 
 let borrow_or_abs_id_to_string (id : borrow_or_abs_id) : string =
   match id with
-  | AbsId id -> "abs@" ^ V.AbstractionId.to_string id
-  | BorrowId id -> "l@" ^ V.BorrowId.to_string id
+  | AbsId id -> "abs@" ^ AbstractionId.to_string id
+  | BorrowId id -> "l@" ^ BorrowId.to_string id
 
 let borrow_or_abs_ids_chain_to_string (ids : borrow_or_abs_ids) : string =
   let ids = List.rev ids in
@@ -88,24 +83,29 @@ let add_borrow_or_abs_id_to_chain (msg : string) (id : borrow_or_abs_id)
 (** Helper function.
   
     This function allows to define in a generic way a comparison of **region types**.
-    See [projections_interesect] for instance.
-    
+    See [projections_intersect] for instance.
+
+    Important: the regions in the types mustn't be erased.
+
     [default]: default boolean to return, when comparing types with no regions
     [combine]: how to combine booleans
     [compare_regions]: how to compare regions
 
     TODO: is there a way of deriving such a comparison?
+    TODO: rename
  *)
 let rec compare_rtys (default : bool) (combine : bool -> bool -> bool)
-    (compare_regions : T.RegionId.id T.region -> T.RegionId.id T.region -> bool)
-    (ty1 : T.rty) (ty2 : T.rty) : bool =
+    (compare_regions : region -> region -> bool) (ty1 : rty) (ty2 : rty) : bool
+    =
   let compare = compare_rtys default combine compare_regions in
+  (* Sanity check - TODO: don't do this at every recursive call *)
+  assert (ty_is_rty ty1 && ty_is_rty ty2);
   (* Normalize the associated types *)
   match (ty1, ty2) with
-  | T.Literal lit1, T.Literal lit2 ->
+  | TLiteral lit1, TLiteral lit2 ->
       assert (lit1 = lit2);
       default
-  | T.Adt (id1, generics1), T.Adt (id2, generics2) ->
+  | TAdt (id1, generics1), TAdt (id2, generics2) ->
       assert (id1 = id2);
       (* There are no regions in the const generics, so we ignore them,
          but we still check they are the same, for sanity *)
@@ -141,7 +141,7 @@ let rec compare_rtys (default : bool) (combine : bool -> bool -> bool)
       in
       (* Combine *)
       combine params_b tys_b
-  | T.Ref (r1, ty1, kind1), T.Ref (r2, ty2, kind2) ->
+  | TRef (r1, ty1, kind1), TRef (r2, ty2, kind2) ->
       (* Sanity check *)
       assert (kind1 = kind2);
       (* Explanation for the case where we check if projections intersect:
@@ -150,10 +150,10 @@ let rec compare_rtys (default : bool) (combine : bool -> bool -> bool)
       let regions_b = compare_regions r1 r2 in
       let tys_b = compare ty1 ty2 in
       combine regions_b tys_b
-  | T.TypeVar id1, T.TypeVar id2 ->
+  | TVar id1, TVar id2 ->
       assert (id1 = id2);
       default
-  | T.TraitType _, T.TraitType _ ->
+  | TTraitType _, TTraitType _ ->
       (* The types should have been normalized. If after normalization we
          get trait types, we can consider them as variables *)
       assert (ty1 = ty2);
@@ -161,8 +161,8 @@ let rec compare_rtys (default : bool) (combine : bool -> bool -> bool)
   | _ ->
       log#lerror
         (lazy
-          ("compare_rtys: unexpected inputs:" ^ "\n- ty1: " ^ T.show_rty ty1
-         ^ "\n- ty2: " ^ T.show_rty ty2));
+          ("compare_rtys: unexpected inputs:" ^ "\n- ty1: " ^ show_ty ty1
+         ^ "\n- ty2: " ^ show_ty ty2));
       raise (Failure "Unreachable")
 
 (** Check if two different projections intersect. This is necessary when
@@ -172,8 +172,8 @@ let rec compare_rtys (default : bool) (combine : bool -> bool -> bool)
     Note that the two abstractions have different views (in terms of regions)
     of the symbolic value (hence the two region types).
 *)
-let projections_intersect (ty1 : T.rty) (rset1 : T.RegionId.Set.t) (ty2 : T.rty)
-    (rset2 : T.RegionId.Set.t) : bool =
+let projections_intersect (ty1 : rty) (rset1 : RegionId.Set.t) (ty2 : rty)
+    (rset2 : RegionId.Set.t) : bool =
   let default = false in
   let combine b1 b2 = b1 || b2 in
   let compare_regions r1 r2 =
@@ -183,9 +183,12 @@ let projections_intersect (ty1 : T.rty) (rset1 : T.RegionId.Set.t) (ty2 : T.rty)
 
 (** Check if the first projection contains the second projection.
     We use this function when checking invariants.
+
+    The regions in the types shouldn't be erased (this function will raise an exception
+    otherwise).
 *)
-let projection_contains (ty1 : T.rty) (rset1 : T.RegionId.Set.t) (ty2 : T.rty)
-    (rset2 : T.RegionId.Set.t) : bool =
+let projection_contains (ty1 : rty) (rset1 : RegionId.Set.t) (ty2 : rty)
+    (rset2 : RegionId.Set.t) : bool =
   let default = true in
   let combine b1 b2 = b1 && b2 in
   let compare_regions r1 r2 =
@@ -201,8 +204,8 @@ let projection_contains (ty1 : T.rty) (rset1 : T.RegionId.Set.t) (ty2 : T.rty)
     the {!InterpreterUtils.abs_or_var_id} is not necessarily {!constructor:Aeneas.InterpreterUtils.abs_or_var_id.VarId} or
     {!constructor:Aeneas.InterpreterUtils.abs_or_var_id.DummyVarId}: there can be concrete loans in abstractions (in the shared values).
  *)
-let lookup_loan_opt (ek : exploration_kind) (l : V.BorrowId.id)
-    (ctx : C.eval_ctx) : (abs_or_var_id * g_loan_content) option =
+let lookup_loan_opt (ek : exploration_kind) (l : BorrowId.id) (ctx : eval_ctx) :
+    (abs_or_var_id * g_loan_content) option =
   (* We store here whether we are inside an abstraction or a value - note that we
    * could also track that with the environment, it would probably be more idiomatic
    * and cleaner *)
@@ -210,19 +213,19 @@ let lookup_loan_opt (ek : exploration_kind) (l : V.BorrowId.id)
 
   let obj =
     object
-      inherit [_] C.iter_eval_ctx as super
+      inherit [_] iter_eval_ctx as super
 
       method! visit_borrow_content env bc =
         match bc with
-        | V.SharedBorrow bid ->
+        | VSharedBorrow bid ->
             (* Nothing specific to do *)
-            super#visit_SharedBorrow env bid
-        | V.ReservedMutBorrow bid ->
+            super#visit_VSharedBorrow env bid
+        | VReservedMutBorrow bid ->
             (* Nothing specific to do *)
-            super#visit_ReservedMutBorrow env bid
-        | V.MutBorrow (bid, mv) ->
+            super#visit_VReservedMutBorrow env bid
+        | VMutBorrow (bid, mv) ->
             (* Control the dive *)
-            if ek.enter_mut_borrows then super#visit_MutBorrow env bid mv
+            if ek.enter_mut_borrows then super#visit_VMutBorrow env bid mv
             else ()
 
       (** We reimplement {!visit_Loan} (rather than the more precise functions
@@ -232,53 +235,53 @@ let lookup_loan_opt (ek : exploration_kind) (l : V.BorrowId.id)
       *)
       method! visit_loan_content env lc =
         match lc with
-        | V.SharedLoan (bids, sv) ->
+        | VSharedLoan (bids, sv) ->
             (* Check if this is the loan we are looking for, and control the dive *)
-            if V.BorrowId.Set.mem l bids then
+            if BorrowId.Set.mem l bids then
               raise (FoundGLoanContent (Concrete lc))
             else if ek.enter_shared_loans then
-              super#visit_SharedLoan env bids sv
+              super#visit_VSharedLoan env bids sv
             else ()
-        | V.MutLoan bid ->
+        | VMutLoan bid ->
             (* Check if this is the loan we are looking for *)
             if bid = l then raise (FoundGLoanContent (Concrete lc))
-            else super#visit_MutLoan env bid
+            else super#visit_VMutLoan env bid
 
       (** Note that we don't control diving inside the abstractions: if we
           allow to dive inside abstractions, we allow to go anywhere
           (because there are no use cases requiring finer control) *)
       method! visit_aloan_content env lc =
         match lc with
-        | V.AMutLoan (bid, av) ->
+        | AMutLoan (bid, av) ->
             if bid = l then raise (FoundGLoanContent (Abstract lc))
             else super#visit_AMutLoan env bid av
-        | V.ASharedLoan (bids, v, av) ->
-            if V.BorrowId.Set.mem l bids then
+        | ASharedLoan (bids, v, av) ->
+            if BorrowId.Set.mem l bids then
               raise (FoundGLoanContent (Abstract lc))
             else super#visit_ASharedLoan env bids v av
-        | V.AEndedMutLoan { given_back = _; child = _; given_back_meta = _ }
-        | V.AEndedSharedLoan (_, _)
-        | V.AIgnoredMutLoan (_, _)
-        | V.AEndedIgnoredMutLoan
+        | AEndedMutLoan { given_back = _; child = _; given_back_meta = _ }
+        | AEndedSharedLoan (_, _)
+        | AIgnoredMutLoan (_, _)
+        | AEndedIgnoredMutLoan
             { given_back = _; child = _; given_back_meta = _ }
-        | V.AIgnoredSharedLoan _ ->
+        | AIgnoredSharedLoan _ ->
             super#visit_aloan_content env lc
 
-      method! visit_Var env bv v =
+      method! visit_EBinding env bv v =
         assert (Option.is_none !abs_or_var);
         abs_or_var :=
           Some
             (match bv with
-            | VarBinder b -> VarId b.C.index
-            | DummyBinder id -> DummyVarId id);
-        super#visit_Var env bv v;
+            | BVar b -> VarId b.index
+            | BDummy id -> DummyVarId id);
+        super#visit_EBinding env bv v;
         abs_or_var := None
 
-      method! visit_Abs env abs =
+      method! visit_EAbs env abs =
         assert (Option.is_none !abs_or_var);
         if ek.enter_abs then (
-          abs_or_var := Some (AbsId abs.V.abs_id);
-          super#visit_Abs env abs;
+          abs_or_var := Some (AbsId abs.abs_id);
+          super#visit_EAbs env abs;
           abs_or_var := None)
         else ()
     end
@@ -297,7 +300,7 @@ let lookup_loan_opt (ek : exploration_kind) (l : V.BorrowId.id)
     The loan is referred to by a borrow id.
     Raises an exception if no loan was found.
  *)
-let lookup_loan (ek : exploration_kind) (l : V.BorrowId.id) (ctx : C.eval_ctx) :
+let lookup_loan (ek : exploration_kind) (l : BorrowId.id) (ctx : eval_ctx) :
     abs_or_var_id * g_loan_content =
   match lookup_loan_opt ek l ctx with
   | None -> raise (Failure "Unreachable")
@@ -309,13 +312,13 @@ let lookup_loan (ek : exploration_kind) (l : V.BorrowId.id) (ctx : C.eval_ctx) :
 
     This is a helper function: it might break invariants.
  *)
-let update_loan (ek : exploration_kind) (l : V.BorrowId.id)
-    (nlc : V.loan_content) (ctx : C.eval_ctx) : C.eval_ctx =
+let update_loan (ek : exploration_kind) (l : BorrowId.id) (nlc : loan_content)
+    (ctx : eval_ctx) : eval_ctx =
   (* We use a reference to check that we update exactly one loan: when updating
    * inside values, we check we don't update more than one loan. Then, upon
    * returning we check that we updated at least once. *)
   let r = ref false in
-  let update () : V.loan_content =
+  let update () : loan_content =
     assert (not !r);
     r := true;
     nlc
@@ -323,32 +326,32 @@ let update_loan (ek : exploration_kind) (l : V.BorrowId.id)
 
   let obj =
     object
-      inherit [_] C.map_eval_ctx as super
+      inherit [_] map_eval_ctx as super
 
       method! visit_borrow_content env bc =
         match bc with
-        | V.SharedBorrow _ | V.ReservedMutBorrow _ ->
+        | VSharedBorrow _ | VReservedMutBorrow _ ->
             (* Nothing specific to do *)
             super#visit_borrow_content env bc
-        | V.MutBorrow (bid, mv) ->
+        | VMutBorrow (bid, mv) ->
             (* Control the dive into mutable borrows *)
-            if ek.enter_mut_borrows then super#visit_MutBorrow env bid mv
-            else V.MutBorrow (bid, mv)
+            if ek.enter_mut_borrows then super#visit_VMutBorrow env bid mv
+            else VMutBorrow (bid, mv)
 
       (** We reimplement {!visit_loan_content} (rather than one of the sub-
           functions) on purpose: exhaustive matches are good for maintenance *)
       method! visit_loan_content env lc =
         match lc with
-        | V.SharedLoan (bids, sv) ->
+        | VSharedLoan (bids, sv) ->
             (* Shared loan: check if this is the loan we are looking for, and
                control the dive. *)
-            if V.BorrowId.Set.mem l bids then update ()
+            if BorrowId.Set.mem l bids then update ()
             else if ek.enter_shared_loans then
-              super#visit_SharedLoan env bids sv
-            else V.SharedLoan (bids, sv)
-        | V.MutLoan bid ->
+              super#visit_VSharedLoan env bids sv
+            else VSharedLoan (bids, sv)
+        | VMutLoan bid ->
             (* Mut loan: checks if this is the loan we are looking for *)
-            if bid = l then update () else super#visit_MutLoan env bid
+            if bid = l then update () else super#visit_VMutLoan env bid
 
       (** Note that once inside the abstractions, we don't control diving
           (there are no use cases requiring finer control).
@@ -372,13 +375,13 @@ let update_loan (ek : exploration_kind) (l : V.BorrowId.id)
 
     This is a helper function: it might break invariants.
  *)
-let update_aloan (ek : exploration_kind) (l : V.BorrowId.id)
-    (nlc : V.aloan_content) (ctx : C.eval_ctx) : C.eval_ctx =
+let update_aloan (ek : exploration_kind) (l : BorrowId.id) (nlc : aloan_content)
+    (ctx : eval_ctx) : eval_ctx =
   (* We use a reference to check that we update exactly one loan: when updating
    * inside values, we check we don't update more than one loan. Then, upon
    * returning we check that we updated at least once. *)
   let r = ref false in
-  let update () : V.aloan_content =
+  let update () : aloan_content =
     assert (not !r);
     r := true;
     nlc
@@ -386,21 +389,21 @@ let update_aloan (ek : exploration_kind) (l : V.BorrowId.id)
 
   let obj =
     object
-      inherit [_] C.map_eval_ctx as super
+      inherit [_] map_eval_ctx as super
 
       method! visit_aloan_content env lc =
         match lc with
-        | V.AMutLoan (bid, av) ->
+        | AMutLoan (bid, av) ->
             if bid = l then update () else super#visit_AMutLoan env bid av
-        | V.ASharedLoan (bids, v, av) ->
-            if V.BorrowId.Set.mem l bids then update ()
+        | ASharedLoan (bids, v, av) ->
+            if BorrowId.Set.mem l bids then update ()
             else super#visit_ASharedLoan env bids v av
-        | V.AEndedMutLoan { given_back = _; child = _; given_back_meta = _ }
-        | V.AEndedSharedLoan (_, _)
-        | V.AIgnoredMutLoan (_, _)
-        | V.AEndedIgnoredMutLoan
+        | AEndedMutLoan { given_back = _; child = _; given_back_meta = _ }
+        | AEndedSharedLoan (_, _)
+        | AIgnoredMutLoan (_, _)
+        | AEndedIgnoredMutLoan
             { given_back = _; child = _; given_back_meta = _ }
-        | V.AIgnoredSharedLoan _ ->
+        | AIgnoredSharedLoan _ ->
             super#visit_aloan_content env lc
 
       (** Note that once inside the abstractions, we don't control diving
@@ -416,50 +419,50 @@ let update_aloan (ek : exploration_kind) (l : V.BorrowId.id)
   ctx
 
 (** Lookup a borrow content from a borrow id. *)
-let lookup_borrow_opt (ek : exploration_kind) (l : V.BorrowId.id)
-    (ctx : C.eval_ctx) : g_borrow_content option =
+let lookup_borrow_opt (ek : exploration_kind) (l : BorrowId.id) (ctx : eval_ctx)
+    : g_borrow_content option =
   let obj =
     object
-      inherit [_] C.iter_eval_ctx as super
+      inherit [_] iter_eval_ctx as super
 
       method! visit_borrow_content env bc =
         match bc with
-        | V.MutBorrow (bid, mv) ->
+        | VMutBorrow (bid, mv) ->
             (* Check the borrow id and control the dive *)
             if bid = l then raise (FoundGBorrowContent (Concrete bc))
-            else if ek.enter_mut_borrows then super#visit_MutBorrow env bid mv
+            else if ek.enter_mut_borrows then super#visit_VMutBorrow env bid mv
             else ()
-        | V.SharedBorrow bid ->
+        | VSharedBorrow bid ->
             (* Check the borrow id *)
             if bid = l then raise (FoundGBorrowContent (Concrete bc)) else ()
-        | V.ReservedMutBorrow bid ->
+        | VReservedMutBorrow bid ->
             (* Check the borrow id *)
             if bid = l then raise (FoundGBorrowContent (Concrete bc)) else ()
 
       method! visit_loan_content env lc =
         match lc with
-        | V.MutLoan bid ->
-            (* Nothing special to do *) super#visit_MutLoan env bid
-        | V.SharedLoan (bids, sv) ->
+        | VMutLoan bid ->
+            (* Nothing special to do *) super#visit_VMutLoan env bid
+        | VSharedLoan (bids, sv) ->
             (* Control the dive *)
-            if ek.enter_shared_loans then super#visit_SharedLoan env bids sv
+            if ek.enter_shared_loans then super#visit_VSharedLoan env bids sv
             else ()
 
       method! visit_aborrow_content env bc =
         match bc with
-        | V.AMutBorrow (bid, av) ->
+        | AMutBorrow (bid, av) ->
             if bid = l then raise (FoundGBorrowContent (Abstract bc))
             else super#visit_AMutBorrow env bid av
-        | V.ASharedBorrow bid ->
+        | ASharedBorrow bid ->
             if bid = l then raise (FoundGBorrowContent (Abstract bc))
             else super#visit_ASharedBorrow env bid
-        | V.AIgnoredMutBorrow (_, _)
-        | V.AEndedMutBorrow _
-        | V.AEndedIgnoredMutBorrow
+        | AIgnoredMutBorrow (_, _)
+        | AEndedMutBorrow _
+        | AEndedIgnoredMutBorrow
             { given_back = _; child = _; given_back_meta = _ }
-        | V.AEndedSharedBorrow ->
+        | AEndedSharedBorrow ->
             super#visit_aborrow_content env bc
-        | V.AProjSharedBorrow asb ->
+        | AProjSharedBorrow asb ->
             if borrow_in_asb l asb then
               raise (FoundGBorrowContent (Abstract bc))
             else ()
@@ -478,8 +481,8 @@ let lookup_borrow_opt (ek : exploration_kind) (l : V.BorrowId.id)
 
     Raise an exception if no loan was found
 *)
-let lookup_borrow (ek : exploration_kind) (l : V.BorrowId.id) (ctx : C.eval_ctx)
-    : g_borrow_content =
+let lookup_borrow (ek : exploration_kind) (l : BorrowId.id) (ctx : eval_ctx) :
+    g_borrow_content =
   match lookup_borrow_opt ek l ctx with
   | None -> raise (Failure "Unreachable")
   | Some lc -> lc
@@ -490,13 +493,13 @@ let lookup_borrow (ek : exploration_kind) (l : V.BorrowId.id) (ctx : C.eval_ctx)
 
     This is a helper function: it might break invariants.   
  *)
-let update_borrow (ek : exploration_kind) (l : V.BorrowId.id)
-    (nbc : V.borrow_content) (ctx : C.eval_ctx) : C.eval_ctx =
+let update_borrow (ek : exploration_kind) (l : BorrowId.id)
+    (nbc : borrow_content) (ctx : eval_ctx) : eval_ctx =
   (* We use a reference to check that we update exactly one borrow: when updating
    * inside values, we check we don't update more than one borrow. Then, upon
    * returning we check that we updated at least once. *)
   let r = ref false in
-  let update () : V.borrow_content =
+  let update () : borrow_content =
     assert (not !r);
     r := true;
     nbc
@@ -504,31 +507,32 @@ let update_borrow (ek : exploration_kind) (l : V.BorrowId.id)
 
   let obj =
     object
-      inherit [_] C.map_eval_ctx as super
+      inherit [_] map_eval_ctx as super
 
       method! visit_borrow_content env bc =
         match bc with
-        | V.MutBorrow (bid, mv) ->
+        | VMutBorrow (bid, mv) ->
             (* Check the id and control dive *)
             if bid = l then update ()
-            else if ek.enter_mut_borrows then super#visit_MutBorrow env bid mv
-            else V.MutBorrow (bid, mv)
-        | V.SharedBorrow bid ->
+            else if ek.enter_mut_borrows then super#visit_VMutBorrow env bid mv
+            else VMutBorrow (bid, mv)
+        | VSharedBorrow bid ->
             (* Check the id *)
-            if bid = l then update () else super#visit_SharedBorrow env bid
-        | V.ReservedMutBorrow bid ->
+            if bid = l then update () else super#visit_VSharedBorrow env bid
+        | VReservedMutBorrow bid ->
             (* Check the id *)
-            if bid = l then update () else super#visit_ReservedMutBorrow env bid
+            if bid = l then update ()
+            else super#visit_VReservedMutBorrow env bid
 
       method! visit_loan_content env lc =
         match lc with
-        | V.SharedLoan (bids, sv) ->
+        | VSharedLoan (bids, sv) ->
             (* Control the dive *)
-            if ek.enter_shared_loans then super#visit_SharedLoan env bids sv
-            else V.SharedLoan (bids, sv)
-        | V.MutLoan bid ->
+            if ek.enter_shared_loans then super#visit_VSharedLoan env bids sv
+            else VSharedLoan (bids, sv)
+        | VMutLoan bid ->
             (* Nothing specific to do *)
-            super#visit_MutLoan env bid
+            super#visit_VMutLoan env bid
 
       method! visit_abs env abs =
         if ek.enter_abs then super#visit_abs env abs else abs
@@ -546,13 +550,13 @@ let update_borrow (ek : exploration_kind) (l : V.BorrowId.id)
 
     This is a helper function: it might break invariants.     
  *)
-let update_aborrow (ek : exploration_kind) (l : V.BorrowId.id) (nv : V.avalue)
-    (ctx : C.eval_ctx) : C.eval_ctx =
+let update_aborrow (ek : exploration_kind) (l : BorrowId.id) (nv : avalue)
+    (ctx : eval_ctx) : eval_ctx =
   (* We use a reference to check that we update exactly one borrow: when updating
    * inside values, we check we don't update more than one borrow. Then, upon
    * returning we check that we updated at least once. *)
   let r = ref false in
-  let update () : V.avalue =
+  let update () : avalue =
     assert (not !r);
     r := true;
     nv
@@ -560,22 +564,22 @@ let update_aborrow (ek : exploration_kind) (l : V.BorrowId.id) (nv : V.avalue)
 
   let obj =
     object
-      inherit [_] C.map_eval_ctx as super
+      inherit [_] map_eval_ctx as super
 
       method! visit_ABorrow env bc =
         match bc with
-        | V.AMutBorrow (bid, av) ->
+        | AMutBorrow (bid, av) ->
             if bid = l then update ()
-            else V.ABorrow (super#visit_AMutBorrow env bid av)
-        | V.ASharedBorrow bid ->
+            else ABorrow (super#visit_AMutBorrow env bid av)
+        | ASharedBorrow bid ->
             if bid = l then update ()
-            else V.ABorrow (super#visit_ASharedBorrow env bid)
-        | V.AIgnoredMutBorrow _ | V.AEndedMutBorrow _ | V.AEndedSharedBorrow
-        | V.AEndedIgnoredMutBorrow _ ->
+            else ABorrow (super#visit_ASharedBorrow env bid)
+        | AIgnoredMutBorrow _ | AEndedMutBorrow _ | AEndedSharedBorrow
+        | AEndedIgnoredMutBorrow _ ->
             super#visit_ABorrow env bc
-        | V.AProjSharedBorrow asb ->
+        | AProjSharedBorrow asb ->
             if borrow_in_asb l asb then update ()
-            else V.ABorrow (super#visit_AProjSharedBorrow env asb)
+            else ABorrow (super#visit_AProjSharedBorrow env asb)
 
       method! visit_abs env abs =
         if ek.enter_abs then super#visit_abs env abs else abs
@@ -588,16 +592,16 @@ let update_aborrow (ek : exploration_kind) (l : V.BorrowId.id) (nv : V.avalue)
   ctx
 
 (** Auxiliary function: see its usage in [end_borrow_get_borrow_in_value] *)
-let update_outer_borrows (outer : V.AbstractionId.id option * borrow_ids option)
-    (x : borrow_ids) : V.AbstractionId.id option * borrow_ids option =
+let update_outer_borrows (outer : AbstractionId.id option * borrow_ids option)
+    (x : borrow_ids) : AbstractionId.id option * borrow_ids option =
   let abs, opt = outer in
   (abs, update_if_none opt x)
 
 (** Return the first loan we find in a value *)
-let get_first_loan_in_value (v : V.typed_value) : V.loan_content option =
+let get_first_loan_in_value (v : typed_value) : loan_content option =
   let obj =
     object
-      inherit [_] V.iter_typed_value
+      inherit [_] iter_typed_value
       method! visit_loan_content _ lc = raise (FoundLoanContent lc)
     end
   in
@@ -608,10 +612,10 @@ let get_first_loan_in_value (v : V.typed_value) : V.loan_content option =
   with FoundLoanContent lc -> Some lc
 
 (** Return the first loan we find in a list of values *)
-let get_first_loan_in_values (vs : V.typed_value list) : V.loan_content option =
+let get_first_loan_in_values (vs : typed_value list) : loan_content option =
   let obj =
     object
-      inherit [_] V.iter_typed_value
+      inherit [_] iter_typed_value
       method! visit_loan_content _ lc = raise (FoundLoanContent lc)
     end
   in
@@ -622,10 +626,10 @@ let get_first_loan_in_values (vs : V.typed_value list) : V.loan_content option =
   with FoundLoanContent lc -> Some lc
 
 (** Return the first borrow we find in a value *)
-let get_first_borrow_in_value (v : V.typed_value) : V.borrow_content option =
+let get_first_borrow_in_value (v : typed_value) : borrow_content option =
   let obj =
     object
-      inherit [_] V.iter_typed_value
+      inherit [_] iter_typed_value
       method! visit_borrow_content _ bc = raise (FoundBorrowContent bc)
     end
   in
@@ -643,10 +647,10 @@ let get_first_borrow_in_value (v : V.typed_value) : V.borrow_content option =
     - if [false]: return the first loan we find, do not dive into borrowed values
  *)
 let get_first_outer_loan_or_borrow_in_value (with_borrows : bool)
-    (v : V.typed_value) : loan_or_borrow_content option =
+    (v : typed_value) : loan_or_borrow_content option =
   let obj =
     object
-      inherit [_] V.iter_typed_value
+      inherit [_] iter_typed_value
 
       method! visit_borrow_content _ bc =
         if with_borrows then raise (FoundBorrowContent bc) else ()
@@ -662,17 +666,13 @@ let get_first_outer_loan_or_borrow_in_value (with_borrows : bool)
   | FoundLoanContent lc -> Some (LoanContent lc)
   | FoundBorrowContent bc -> Some (BorrowContent bc)
 
-type gproj_borrows =
-  | AProjBorrows of V.AbstractionId.id * V.symbolic_value
-  | ProjBorrows of V.symbolic_value
-
 let proj_borrows_intersects_proj_loans
-    (proj_borrows : T.RegionId.Set.t * V.symbolic_value * T.rty)
-    (proj_loans : T.RegionId.Set.t * V.symbolic_value) : bool =
+    (proj_borrows : RegionId.Set.t * symbolic_value * rty)
+    (proj_loans : RegionId.Set.t * symbolic_value) : bool =
   let b_regions, b_sv, b_ty = proj_borrows in
   let l_regions, l_sv = proj_loans in
   if same_symbolic_id b_sv l_sv then
-    projections_intersect l_sv.V.sv_ty l_regions b_ty b_regions
+    projections_intersect l_sv.sv_ty l_regions b_ty b_regions
   else false
 
 (** Result of looking up aproj_borrows which intersect a given aproj_loans in
@@ -689,8 +689,8 @@ let proj_borrows_intersects_proj_loans
     found, as well as the projection types used in those abstractions.
 *)
 type looked_up_aproj_borrows =
-  | NonSharedProj of V.AbstractionId.id * T.rty
-  | SharedProjs of (V.AbstractionId.id * T.rty) list
+  | NonSharedProj of AbstractionId.id * rty
+  | SharedProjs of (AbstractionId.id * rty) list
 
 (** Lookup the aproj_borrows (including aproj_shared_borrows) over a
     symbolic value which intersect a given set of regions.
@@ -701,15 +701,15 @@ type looked_up_aproj_borrows =
     This is a helper function.
 *)
 let lookup_intersecting_aproj_borrows_opt (lookup_shared : bool)
-    (regions : T.RegionId.Set.t) (sv : V.symbolic_value) (ctx : C.eval_ctx) :
+    (regions : RegionId.Set.t) (sv : symbolic_value) (ctx : eval_ctx) :
     looked_up_aproj_borrows option =
   let found : looked_up_aproj_borrows option ref = ref None in
-  let set_non_shared ((id, ty) : V.AbstractionId.id * T.rty) : unit =
+  let set_non_shared ((id, ty) : AbstractionId.id * rty) : unit =
     match !found with
     | None -> found := Some (NonSharedProj (id, ty))
     | Some _ -> raise (Failure "Unreachable")
   in
-  let add_shared (x : V.AbstractionId.id * T.rty) : unit =
+  let add_shared (x : AbstractionId.id * rty) : unit =
     match !found with
     | None -> found := Some (SharedProjs [ x ])
     | Some (SharedProjs pl) -> found := Some (SharedProjs (x :: pl))
@@ -718,7 +718,7 @@ let lookup_intersecting_aproj_borrows_opt (lookup_shared : bool)
   let check_add_proj_borrows (is_shared : bool) abs sv' proj_ty =
     if
       proj_borrows_intersects_proj_loans
-        (abs.V.regions, sv', proj_ty)
+        (abs.regions, sv', proj_ty)
         (regions, sv)
     then
       let x = (abs.abs_id, proj_ty) in
@@ -727,7 +727,7 @@ let lookup_intersecting_aproj_borrows_opt (lookup_shared : bool)
   in
   let obj =
     object
-      inherit [_] C.iter_eval_ctx as super
+      inherit [_] iter_eval_ctx as super
       method! visit_abs _ abs = super#visit_abs (Some abs) abs
 
       method! visit_abstract_shared_borrow abs asb =
@@ -739,8 +739,8 @@ let lookup_intersecting_aproj_borrows_opt (lookup_shared : bool)
         if lookup_shared then
           let abs = Option.get abs in
           match asb with
-          | V.AsbBorrow _ -> ()
-          | V.AsbProjReborrows (sv', proj_ty) ->
+          | AsbBorrow _ -> ()
+          | AsbProjReborrows (sv', proj_ty) ->
               let is_shared = true in
               check_add_proj_borrows is_shared abs sv' proj_ty
         else ()
@@ -772,9 +772,8 @@ let lookup_intersecting_aproj_borrows_opt (lookup_shared : bool)
     Returns the id of the owning abstraction, and the projection type used in
     this abstraction.
 *)
-let lookup_intersecting_aproj_borrows_not_shared_opt
-    (regions : T.RegionId.Set.t) (sv : V.symbolic_value) (ctx : C.eval_ctx) :
-    (V.AbstractionId.id * T.rty) option =
+let lookup_intersecting_aproj_borrows_not_shared_opt (regions : RegionId.Set.t)
+    (sv : symbolic_value) (ctx : eval_ctx) : (AbstractionId.id * rty) option =
   let lookup_shared = false in
   match lookup_intersecting_aproj_borrows_opt lookup_shared regions sv ctx with
   | None -> None
@@ -787,10 +786,10 @@ let lookup_intersecting_aproj_borrows_not_shared_opt
     This is a helper function: it might break invariants.
  *)
 let update_intersecting_aproj_borrows (can_update_shared : bool)
-    (update_shared : V.AbstractionId.id -> T.rty -> V.abstract_shared_borrows)
-    (update_non_shared : V.AbstractionId.id -> T.rty -> V.aproj)
-    (regions : T.RegionId.Set.t) (sv : V.symbolic_value) (ctx : C.eval_ctx) :
-    C.eval_ctx =
+    (update_shared : AbstractionId.id -> rty -> abstract_shared_borrows)
+    (update_non_shared : AbstractionId.id -> rty -> aproj)
+    (regions : RegionId.Set.t) (sv : symbolic_value) (ctx : eval_ctx) : eval_ctx
+    =
   (* Small helpers for sanity checks *)
   let shared = ref None in
   let add_shared () =
@@ -804,7 +803,7 @@ let update_intersecting_aproj_borrows (can_update_shared : bool)
   let check_proj_borrows is_shared abs sv' proj_ty =
     if
       proj_borrows_intersects_proj_loans
-        (abs.V.regions, sv', proj_ty)
+        (abs.regions, sv', proj_ty)
         (regions, sv)
     then (
       if is_shared then add_shared () else set_non_shared ();
@@ -814,7 +813,7 @@ let update_intersecting_aproj_borrows (can_update_shared : bool)
   (* The visitor *)
   let obj =
     object
-      inherit [_] C.map_eval_ctx as super
+      inherit [_] map_eval_ctx as super
       method! visit_abs _ abs = super#visit_abs (Some abs) abs
 
       method! visit_abstract_shared_borrows abs asb =
@@ -823,11 +822,10 @@ let update_intersecting_aproj_borrows (can_update_shared : bool)
         (* Explore *)
         if can_update_shared then
           let abs = Option.get abs in
-          let update (asb : V.abstract_shared_borrow) :
-              V.abstract_shared_borrows =
+          let update (asb : abstract_shared_borrow) : abstract_shared_borrows =
             match asb with
-            | V.AsbBorrow _ -> [ asb ]
-            | V.AsbProjReborrows (sv', proj_ty) ->
+            | AsbBorrow _ -> [ asb ]
+            | AsbProjReborrows (sv', proj_ty) ->
                 let is_shared = true in
                 if check_proj_borrows is_shared abs sv' proj_ty then
                   update_shared abs.abs_id proj_ty
@@ -863,8 +861,8 @@ let update_intersecting_aproj_borrows (can_update_shared : bool)
 
     This is a helper function: it might break invariants.
  *)
-let update_intersecting_aproj_borrows_non_shared (regions : T.RegionId.Set.t)
-    (sv : V.symbolic_value) (nv : V.aproj) (ctx : C.eval_ctx) : C.eval_ctx =
+let update_intersecting_aproj_borrows_non_shared (regions : RegionId.Set.t)
+    (sv : symbolic_value) (nv : aproj) (ctx : eval_ctx) : eval_ctx =
   (* Small helpers *)
   let can_update_shared = false in
   let update_shared _ _ = raise (Failure "Unexpected") in
@@ -889,8 +887,8 @@ let update_intersecting_aproj_borrows_non_shared (regions : T.RegionId.Set.t)
 
     This is a helper function: it might break invariants.
  *)
-let remove_intersecting_aproj_borrows_shared (regions : T.RegionId.Set.t)
-    (sv : V.symbolic_value) (ctx : C.eval_ctx) : C.eval_ctx =
+let remove_intersecting_aproj_borrows_shared (regions : RegionId.Set.t)
+    (sv : symbolic_value) (ctx : eval_ctx) : eval_ctx =
   (* Small helpers *)
   let can_update_shared = true in
   let update_shared _ _ = [] in
@@ -921,20 +919,24 @@ let remove_intersecting_aproj_borrows_shared (regions : T.RegionId.Set.t)
     
     Note that for sanity, this function checks that we update *at least* one
     projector of loans.
+
+    [proj_ty]: shouldn't contain erased regions.
         
     [subst]: takes as parameters the abstraction in which we perform the
     substitution and the list of given back values at the projector of
-    loans where we perform the substitution (see the fields in {!V.AProjLoans}).
+    loans where we perform the substitution (see the fields in {!AProjLoans}).
     Note that the symbolic value at this place is necessarily equal to [sv],
     which is why we don't give it as parameters.
  *)
-let update_intersecting_aproj_loans (proj_regions : T.RegionId.Set.t)
-    (proj_ty : T.rty) (sv : V.symbolic_value)
-    (subst : V.abs -> (V.msymbolic_value * V.aproj) list -> V.aproj)
-    (ctx : C.eval_ctx) : C.eval_ctx =
+let update_intersecting_aproj_loans (proj_regions : RegionId.Set.t)
+    (proj_ty : rty) (sv : symbolic_value)
+    (subst : abs -> (msymbolic_value * aproj) list -> aproj) (ctx : eval_ctx) :
+    eval_ctx =
+  (* *)
+  assert (ty_is_rty proj_ty);
   (* Small helpers for sanity checks *)
   let updated = ref false in
-  let update abs local_given_back : V.aproj =
+  let update abs local_given_back : aproj =
     (* Note that we can update more than once! *)
     updated := true;
     subst abs local_given_back
@@ -942,7 +944,7 @@ let update_intersecting_aproj_loans (proj_regions : T.RegionId.Set.t)
   (* The visitor *)
   let obj =
     object
-      inherit [_] C.map_eval_ctx as super
+      inherit [_] map_eval_ctx as super
       method! visit_abs _ abs = super#visit_abs (Some abs) abs
 
       method! visit_aproj abs sproj =
@@ -955,8 +957,7 @@ let update_intersecting_aproj_loans (proj_regions : T.RegionId.Set.t)
             if same_symbolic_id sv sv' then (
               assert (sv.sv_ty = sv'.sv_ty);
               if
-                projections_intersect proj_ty proj_regions sv'.V.sv_ty
-                  abs.regions
+                projections_intersect proj_ty proj_regions sv'.sv_ty abs.regions
               then update abs given_back
               else super#visit_aproj (Some abs) sproj)
             else super#visit_aproj (Some abs) sproj
@@ -969,18 +970,18 @@ let update_intersecting_aproj_loans (proj_regions : T.RegionId.Set.t)
   (* Return *)
   ctx
 
-(** Helper function: lookup an {!V.AProjLoans} by using an abstraction id and a
+(** Helper function: lookup an {!AProjLoans} by using an abstraction id and a
     symbolic value.
     
     We return the information from the looked up projector of loans. See the
-    fields in {!V.AProjLoans} (we don't return the symbolic value, because it
+    fields in {!AProjLoans} (we don't return the symbolic value, because it
     is equal to [sv]).
     
     Sanity check: we check that there is exactly one projector which corresponds
     to the couple (abstraction id, symbolic value).
  *)
-let lookup_aproj_loans (abs_id : V.AbstractionId.id) (sv : V.symbolic_value)
-    (ctx : C.eval_ctx) : (V.msymbolic_value * V.aproj) list =
+let lookup_aproj_loans (abs_id : AbstractionId.id) (sv : symbolic_value)
+    (ctx : eval_ctx) : (msymbolic_value * aproj) list =
   (* Small helpers for sanity checks *)
   let found = ref None in
   let set_found x =
@@ -991,12 +992,12 @@ let lookup_aproj_loans (abs_id : V.AbstractionId.id) (sv : V.symbolic_value)
   (* The visitor *)
   let obj =
     object
-      inherit [_] C.iter_eval_ctx as super
+      inherit [_] iter_eval_ctx as super
 
       method! visit_abs _ abs =
         if abs.abs_id = abs_id then super#visit_abs (Some abs) abs else ()
 
-      method! visit_aproj (abs : V.abs option) sproj =
+      method! visit_aproj (abs : abs option) sproj =
         (match sproj with
         | AProjBorrows _ | AEndedProjLoans _ | AEndedProjBorrows _
         | AIgnoredProjBorrows ->
@@ -1024,8 +1025,8 @@ let lookup_aproj_loans (abs_id : V.AbstractionId.id) (sv : V.symbolic_value)
     Sanity check: we check that there is exactly one projector which corresponds
     to the couple (abstraction id, symbolic value).
  *)
-let update_aproj_loans (abs_id : V.AbstractionId.id) (sv : V.symbolic_value)
-    (nproj : V.aproj) (ctx : C.eval_ctx) : C.eval_ctx =
+let update_aproj_loans (abs_id : AbstractionId.id) (sv : symbolic_value)
+    (nproj : aproj) (ctx : eval_ctx) : eval_ctx =
   (* Small helpers for sanity checks *)
   let found = ref false in
   let update () =
@@ -1037,12 +1038,12 @@ let update_aproj_loans (abs_id : V.AbstractionId.id) (sv : V.symbolic_value)
   (* The visitor *)
   let obj =
     object
-      inherit [_] C.map_eval_ctx as super
+      inherit [_] map_eval_ctx as super
 
       method! visit_abs _ abs =
         if abs.abs_id = abs_id then super#visit_abs (Some abs) abs else abs
 
-      method! visit_aproj (abs : V.abs option) sproj =
+      method! visit_aproj (abs : abs option) sproj =
         match sproj with
         | AProjBorrows _ | AEndedProjLoans _ | AEndedProjBorrows _
         | AIgnoredProjBorrows ->
@@ -1073,8 +1074,8 @@ let update_aproj_loans (abs_id : V.AbstractionId.id) (sv : V.symbolic_value)
     
     TODO: factorize with {!update_aproj_loans}?
  *)
-let update_aproj_borrows (abs_id : V.AbstractionId.id) (sv : V.symbolic_value)
-    (nproj : V.aproj) (ctx : C.eval_ctx) : C.eval_ctx =
+let update_aproj_borrows (abs_id : AbstractionId.id) (sv : symbolic_value)
+    (nproj : aproj) (ctx : eval_ctx) : eval_ctx =
   (* Small helpers for sanity checks *)
   let found = ref false in
   let update () =
@@ -1086,12 +1087,12 @@ let update_aproj_borrows (abs_id : V.AbstractionId.id) (sv : V.symbolic_value)
   (* The visitor *)
   let obj =
     object
-      inherit [_] C.map_eval_ctx as super
+      inherit [_] map_eval_ctx as super
 
       method! visit_abs _ abs =
         if abs.abs_id = abs_id then super#visit_abs (Some abs) abs else abs
 
-      method! visit_aproj (abs : V.abs option) sproj =
+      method! visit_aproj (abs : abs option) sproj =
         match sproj with
         | AProjLoans _ | AEndedProjLoans _ | AEndedProjBorrows _
         | AIgnoredProjBorrows ->
@@ -1114,26 +1115,26 @@ let update_aproj_borrows (abs_id : V.AbstractionId.id) (sv : V.symbolic_value)
 
 (** Helper function: might break invariants.
 
-    Converts an {!V.AProjLoans} to an {!V.AEndedProjLoans}. The projector is identified
+    Converts an {!AProjLoans} to an {!AEndedProjLoans}. The projector is identified
     by a symbolic value and an abstraction id.
  *)
-let update_aproj_loans_to_ended (abs_id : V.AbstractionId.id)
-    (sv : V.symbolic_value) (ctx : C.eval_ctx) : C.eval_ctx =
+let update_aproj_loans_to_ended (abs_id : AbstractionId.id)
+    (sv : symbolic_value) (ctx : eval_ctx) : eval_ctx =
   (* Lookup the projector of loans *)
   let given_back = lookup_aproj_loans abs_id sv ctx in
   (* Create the new value for the projector *)
-  let nproj = V.AEndedProjLoans (sv, given_back) in
+  let nproj = AEndedProjLoans (sv, given_back) in
   (* Insert it *)
   let ctx = update_aproj_loans abs_id sv nproj ctx in
   (* Return *)
   ctx
 
-let no_aproj_over_symbolic_in_context (sv : V.symbolic_value) (ctx : C.eval_ctx)
-    : unit =
+let no_aproj_over_symbolic_in_context (sv : symbolic_value) (ctx : eval_ctx) :
+    unit =
   (* The visitor *)
   let obj =
     object
-      inherit [_] C.iter_eval_ctx as super
+      inherit [_] iter_eval_ctx as super
 
       method! visit_aproj env sproj =
         (match sproj with
@@ -1154,44 +1155,44 @@ let no_aproj_over_symbolic_in_context (sv : V.symbolic_value) (ctx : C.eval_ctx)
     
     **Remark:** we don't take the *ignored* mut/shared loans into account.
  *)
-let get_first_non_ignored_aloan_in_abstraction (abs : V.abs) :
+let get_first_non_ignored_aloan_in_abstraction (abs : abs) :
     borrow_ids_or_symbolic_value option =
   (* Explore to find a loan *)
   let obj =
     object
-      inherit [_] V.iter_abs as super
+      inherit [_] iter_abs as super
 
       method! visit_aloan_content env lc =
         match lc with
-        | V.AMutLoan (bid, _) -> raise (FoundBorrowIds (Borrow bid))
-        | V.ASharedLoan (bids, _, _) -> raise (FoundBorrowIds (Borrows bids))
-        | V.AEndedMutLoan { given_back = _; child = _; given_back_meta = _ }
-        | V.AEndedSharedLoan (_, _) ->
+        | AMutLoan (bid, _) -> raise (FoundBorrowIds (Borrow bid))
+        | ASharedLoan (bids, _, _) -> raise (FoundBorrowIds (Borrows bids))
+        | AEndedMutLoan { given_back = _; child = _; given_back_meta = _ }
+        | AEndedSharedLoan (_, _) ->
             super#visit_aloan_content env lc
-        | V.AIgnoredMutLoan (_, _) ->
+        | AIgnoredMutLoan (_, _) ->
             (* Ignore *)
             super#visit_aloan_content env lc
-        | V.AEndedIgnoredMutLoan
+        | AEndedIgnoredMutLoan
             { given_back = _; child = _; given_back_meta = _ }
-        | V.AIgnoredSharedLoan _ ->
+        | AIgnoredSharedLoan _ ->
             (* Ignore *)
             super#visit_aloan_content env lc
 
       (** We may need to visit loan contents because of shared values *)
       method! visit_loan_content _ lc =
         match lc with
-        | V.MutLoan _ ->
+        | VMutLoan _ ->
             (* The mut loan linked to the mutable borrow present in a shared
              * value in an abstraction should be in an AProjBorrows *)
             raise (Failure "Unreachable")
-        | V.SharedLoan (bids, _) -> raise (FoundBorrowIds (Borrows bids))
+        | VSharedLoan (bids, _) -> raise (FoundBorrowIds (Borrows bids))
 
       method! visit_aproj env sproj =
         (match sproj with
-        | V.AProjBorrows (_, _)
-        | V.AEndedProjLoans _ | V.AEndedProjBorrows _ | V.AIgnoredProjBorrows ->
+        | AProjBorrows (_, _)
+        | AEndedProjLoans _ | AEndedProjBorrows _ | AIgnoredProjBorrows ->
             ()
-        | V.AProjLoans (sv, _) -> raise (ValuesUtils.FoundSymbolicValue sv));
+        | AProjLoans (sv, _) -> raise (ValuesUtils.FoundSymbolicValue sv));
         super#visit_aproj env sproj
     end
   in
@@ -1207,16 +1208,15 @@ let get_first_non_ignored_aloan_in_abstraction (abs : V.abs) :
       (* There are loan projections over symbolic values *)
       Some (SymbolicValue sv)
 
-let lookup_shared_value_opt (ctx : C.eval_ctx) (bid : V.BorrowId.id) :
-    V.typed_value option =
+let lookup_shared_value_opt (ctx : eval_ctx) (bid : BorrowId.id) :
+    typed_value option =
   match lookup_loan_opt ek_all bid ctx with
   | None -> None
   | Some (_, lc) -> (
       match lc with
-      | Concrete (SharedLoan (_, sv)) | Abstract (ASharedLoan (_, sv, _)) ->
+      | Concrete (VSharedLoan (_, sv)) | Abstract (ASharedLoan (_, sv, _)) ->
           Some sv
       | _ -> None)
 
-let lookup_shared_value (ctx : C.eval_ctx) (bid : V.BorrowId.id) : V.typed_value
-    =
+let lookup_shared_value (ctx : eval_ctx) (bid : BorrowId.id) : typed_value =
   Option.get (lookup_shared_value_opt ctx bid)
diff --git a/compiler/InterpreterExpansion.ml b/compiler/InterpreterExpansion.ml
index b267bb51..d7f5fcd5 100644
--- a/compiler/InterpreterExpansion.ml
+++ b/compiler/InterpreterExpansion.ml
@@ -3,26 +3,20 @@
  * some path utilities for replacement. We might change that in the future (by
  * using indices to identify the values for instance). *)
 
-module T = Types
-module PV = PrimitiveValues
-module V = Values
-module E = Expressions
-module C = Contexts
-module Subst = Substitute
-module Assoc = AssociatedTypes
-module L = Logging
+open Types
+open Values
+open Contexts
 open TypesUtils
-module Inv = Invariants
-module S = SynthesizeSymbolic
 module SA = SymbolicAst
 open Cps
 open ValuesUtils
 open InterpreterUtils
 open InterpreterProjectors
-open InterpreterBorrows
+open Print.EvalCtx
+module S = SynthesizeSymbolic
 
 (** The local logger *)
-let log = L.expansion_log
+let log = Logging.expansion_log
 
 (** Projector kind *)
 type proj_kind = LoanProj | BorrowProj
@@ -53,10 +47,10 @@ type proj_kind = LoanProj | BorrowProj
     Note that 2. and 3. may have a little bit of duplicated code, but hopefully
     it would make things clearer.
 *)
-let apply_symbolic_expansion_to_target_avalues (config : C.config)
+let apply_symbolic_expansion_to_target_avalues (config : config)
     (allow_reborrows : bool) (proj_kind : proj_kind)
-    (original_sv : V.symbolic_value) (expansion : V.symbolic_expansion)
-    (ctx : C.eval_ctx) : C.eval_ctx =
+    (original_sv : symbolic_value) (expansion : symbolic_expansion)
+    (ctx : eval_ctx) : eval_ctx =
   (* Symbolic values contained in the expansion might contain already ended regions *)
   let check_symbolic_no_ended = false in
   (* Prepare reborrows registration *)
@@ -66,7 +60,7 @@ let apply_symbolic_expansion_to_target_avalues (config : C.config)
   (* Visitor to apply the expansion *)
   let obj =
     object (self)
-      inherit [_] C.map_eval_ctx as super
+      inherit [_] map_eval_ctx as super
 
       (** When visiting an abstraction, we remember the regions it owns to be
           able to properly reduce projectors when expanding symbolic values *)
@@ -94,12 +88,12 @@ let apply_symbolic_expansion_to_target_avalues (config : C.config)
         (* Explore in depth first - we won't update anything: we simply
          * want to check we don't have to expand inner symbolic value *)
         match (aproj, proj_kind) with
-        | V.AEndedProjBorrows _, _ -> V.ASymbolic aproj
-        | V.AEndedProjLoans _, _ ->
+        | AEndedProjBorrows _, _ -> ASymbolic aproj
+        | AEndedProjLoans _, _ ->
             (* Explore the given back values to make sure we don't have to expand
              * anything in there *)
-            V.ASymbolic (self#visit_aproj (Some current_abs) aproj)
-        | V.AProjLoans (sv, given_back), LoanProj ->
+            ASymbolic (self#visit_aproj (Some current_abs) aproj)
+        | AProjLoans (sv, given_back), LoanProj ->
             (* Check if this is the symbolic value we are looking for *)
             if same_symbolic_id sv original_sv then (
               (* There mustn't be any given back values *)
@@ -107,14 +101,14 @@ let apply_symbolic_expansion_to_target_avalues (config : C.config)
               (* Apply the projector *)
               let projected_value =
                 apply_proj_loans_on_symbolic_expansion proj_regions
-                  ancestors_regions expansion original_sv.V.sv_ty
+                  ancestors_regions expansion original_sv.sv_ty
               in
               (* Replace *)
-              projected_value.V.value)
+              projected_value.value)
             else
               (* Not the searched symbolic value: nothing to do *)
               super#visit_ASymbolic (Some current_abs) aproj
-        | V.AProjBorrows (sv, proj_ty), BorrowProj ->
+        | AProjBorrows (sv, proj_ty), BorrowProj ->
             (* Check if this is the symbolic value we are looking for *)
             if same_symbolic_id sv original_sv then
               (* Convert the symbolic expansion to a value on which we can
@@ -132,15 +126,15 @@ let apply_symbolic_expansion_to_target_avalues (config : C.config)
                   proj_regions ancestors_regions expansion proj_ty
               in
               (* Replace *)
-              projected_value.V.value
+              projected_value.value
             else
               (* Not the searched symbolic value: nothing to do *)
               super#visit_ASymbolic (Some current_abs) aproj
-        | V.AProjLoans _, BorrowProj
-        | V.AProjBorrows (_, _), LoanProj
-        | V.AIgnoredProjBorrows, _ ->
+        | AProjLoans _, BorrowProj
+        | AProjBorrows (_, _), LoanProj
+        | AIgnoredProjBorrows, _ ->
             (* Nothing to do *)
-            V.ASymbolic aproj
+            ASymbolic aproj
     end
   in
   (* Apply the expansion *)
@@ -151,9 +145,9 @@ let apply_symbolic_expansion_to_target_avalues (config : C.config)
 (** Auxiliary function.
     Apply a symbolic expansion to avalues in a context.
 *)
-let apply_symbolic_expansion_to_avalues (config : C.config)
-    (allow_reborrows : bool) (original_sv : V.symbolic_value)
-    (expansion : V.symbolic_expansion) (ctx : C.eval_ctx) : C.eval_ctx =
+let apply_symbolic_expansion_to_avalues (config : config)
+    (allow_reborrows : bool) (original_sv : symbolic_value)
+    (expansion : symbolic_expansion) (ctx : eval_ctx) : eval_ctx =
   let apply_expansion proj_kind ctx =
     apply_symbolic_expansion_to_target_avalues config allow_reborrows proj_kind
       original_sv expansion ctx
@@ -168,9 +162,8 @@ let apply_symbolic_expansion_to_avalues (config : C.config)
     Simply replace the symbolic values (*not avalues*) in the context with
     a given value. Will break invariants if not used properly.
 *)
-let replace_symbolic_values (at_most_once : bool)
-    (original_sv : V.symbolic_value) (nv : V.value) (ctx : C.eval_ctx) :
-    C.eval_ctx =
+let replace_symbolic_values (at_most_once : bool) (original_sv : symbolic_value)
+    (nv : value) (ctx : eval_ctx) : eval_ctx =
   (* Count *)
   let replaced = ref false in
   let replace () =
@@ -181,11 +174,11 @@ let replace_symbolic_values (at_most_once : bool)
   (* Visitor to apply the substitution *)
   let obj =
     object
-      inherit [_] C.map_eval_ctx as super
+      inherit [_] map_eval_ctx as super
 
-      method! visit_Symbolic env spc =
+      method! visit_VSymbolic env spc =
         if same_symbolic_id spc original_sv then replace ()
-        else super#visit_Symbolic env spc
+        else super#visit_VSymbolic env spc
     end
   in
   (* Apply the substitution *)
@@ -193,13 +186,13 @@ let replace_symbolic_values (at_most_once : bool)
   (* Return *)
   ctx
 
-let apply_symbolic_expansion_non_borrow (config : C.config)
-    (original_sv : V.symbolic_value) (expansion : V.symbolic_expansion)
-    (ctx : C.eval_ctx) : C.eval_ctx =
+let apply_symbolic_expansion_non_borrow (config : config)
+    (original_sv : symbolic_value) (expansion : symbolic_expansion)
+    (ctx : eval_ctx) : eval_ctx =
   (* Apply the expansion to non-abstraction values *)
   let nv = symbolic_expansion_non_borrow_to_value original_sv expansion in
   let at_most_once = false in
-  let ctx = replace_symbolic_values at_most_once original_sv nv.V.value ctx in
+  let ctx = replace_symbolic_values at_most_once original_sv nv.value ctx in
   (* Apply the expansion to abstraction values *)
   let allow_reborrows = false in
   apply_symbolic_expansion_to_avalues config allow_reborrows original_sv
@@ -211,51 +204,52 @@ let apply_symbolic_expansion_non_borrow (config : C.config)
     The function might return a list of values if the symbolic value to expand
     is an enumeration.
     
+    [generics]: mustn't contain erased regions.
     [expand_enumerations] controls the expansion of enumerations: if false, it
     doesn't allow the expansion of enumerations *containing several variants*.
  *)
 let compute_expanded_symbolic_non_assumed_adt_value (expand_enumerations : bool)
-    (kind : V.sv_kind) (def_id : T.TypeDeclId.id) (generics : T.rgeneric_args)
-    (ctx : C.eval_ctx) : V.symbolic_expansion list =
+    (kind : sv_kind) (def_id : TypeDeclId.id) (generics : generic_args)
+    (ctx : eval_ctx) : symbolic_expansion list =
   (* Lookup the definition and check if it is an enumeration with several
    * variants *)
-  let def = C.ctx_lookup_type_decl ctx def_id in
-  assert (List.length generics.regions = List.length def.T.generics.regions);
+  let def = ctx_lookup_type_decl ctx def_id in
+  assert (List.length generics.regions = List.length def.generics.regions);
   (* Retrieve, for every variant, the list of its instantiated field types *)
   let variants_fields_types =
-    Assoc.type_decl_get_inst_norm_variants_fields_rtypes ctx def generics
+    AssociatedTypes.type_decl_get_inst_norm_variants_fields_rtypes ctx def
+      generics
   in
   (* Check if there is strictly more than one variant *)
   if List.length variants_fields_types > 1 && not expand_enumerations then
     raise (Failure "Not allowed to expand enumerations with several variants");
   (* Initialize the expanded value for a given variant *)
-  let initialize
-      ((variant_id, field_types) : T.VariantId.id option * T.rty list) :
-      V.symbolic_expansion =
+  let initialize ((variant_id, field_types) : VariantId.id option * rty list) :
+      symbolic_expansion =
     let field_values =
-      List.map (fun (ty : T.rty) -> mk_fresh_symbolic_value kind ty) field_types
+      List.map (fun (ty : rty) -> mk_fresh_symbolic_value kind ty) field_types
     in
-    let see = V.SeAdt (variant_id, field_values) in
+    let see = SeAdt (variant_id, field_values) in
     see
   in
   (* Initialize all the expanded values of all the variants *)
   List.map initialize variants_fields_types
 
-let compute_expanded_symbolic_tuple_value (kind : V.sv_kind)
-    (field_types : T.rty list) : V.symbolic_expansion =
+let compute_expanded_symbolic_tuple_value (kind : sv_kind)
+    (field_types : rty list) : symbolic_expansion =
   (* Generate the field values *)
   let field_values =
     List.map (fun sv_ty -> mk_fresh_symbolic_value kind sv_ty) field_types
   in
   let variant_id = None in
-  let see = V.SeAdt (variant_id, field_values) in
+  let see = SeAdt (variant_id, field_values) in
   see
 
-let compute_expanded_symbolic_box_value (kind : V.sv_kind) (boxed_ty : T.rty) :
-    V.symbolic_expansion =
+let compute_expanded_symbolic_box_value (kind : sv_kind) (boxed_ty : rty) :
+    symbolic_expansion =
   (* Introduce a fresh symbolic value *)
   let boxed_value = mk_fresh_symbolic_value kind boxed_ty in
-  let see = V.SeAdt (None, [ boxed_value ]) in
+  let see = SeAdt (None, [ boxed_value ]) in
   see
 
 (** Compute the expansion of an adt value.
@@ -263,55 +257,56 @@ let compute_expanded_symbolic_box_value (kind : V.sv_kind) (boxed_ty : T.rty) :
     The function might return a list of values if the symbolic value to expand
     is an enumeration.
 
+    [generics]: the regions shouldn't have been erased.
     [expand_enumerations] controls the expansion of enumerations: if [false], it
     doesn't allow the expansion of enumerations *containing several variants*.
  *)
 let compute_expanded_symbolic_adt_value (expand_enumerations : bool)
-    (kind : V.sv_kind) (adt_id : T.type_id) (generics : T.rgeneric_args)
-    (ctx : C.eval_ctx) : V.symbolic_expansion list =
+    (kind : sv_kind) (adt_id : type_id) (generics : generic_args)
+    (ctx : eval_ctx) : symbolic_expansion list =
   match (adt_id, generics.regions, generics.types) with
-  | T.AdtId def_id, _, _ ->
+  | TAdtId def_id, _, _ ->
       compute_expanded_symbolic_non_assumed_adt_value expand_enumerations kind
         def_id generics ctx
-  | T.Tuple, [], _ ->
+  | TTuple, [], _ ->
       [ compute_expanded_symbolic_tuple_value kind generics.types ]
-  | T.Assumed T.Box, [], [ boxed_ty ] ->
+  | TAssumed TBox, [], [ boxed_ty ] ->
       [ compute_expanded_symbolic_box_value kind boxed_ty ]
   | _ ->
       raise
         (Failure "compute_expanded_symbolic_adt_value: unexpected combination")
 
-let expand_symbolic_value_shared_borrow (config : C.config)
-    (original_sv : V.symbolic_value) (original_sv_place : SA.mplace option)
-    (ref_ty : T.rty) : cm_fun =
+let expand_symbolic_value_shared_borrow (config : config)
+    (original_sv : symbolic_value) (original_sv_place : SA.mplace option)
+    (ref_ty : rty) : cm_fun =
  fun cf ctx ->
   (* First, replace the projectors on borrows.
    * The important point is that the symbolic value to expand may appear
    * several times, if it has been copied. In this case, we need to introduce
    * one fresh borrow id per instance.
    *)
-  let borrows = ref V.BorrowId.Set.empty in
+  let borrows = ref BorrowId.Set.empty in
   let fresh_borrow () =
-    let bid' = C.fresh_borrow_id () in
-    borrows := V.BorrowId.Set.add bid' !borrows;
+    let bid' = fresh_borrow_id () in
+    borrows := BorrowId.Set.add bid' !borrows;
     bid'
   in
   (* Small utility used on shared borrows in abstractions (regular borrow
    * projector and asb).
    * Returns [Some] if the symbolic value has been expanded to an asb list,
    * [None] otherwise *)
-  let reborrow_ashared proj_regions (sv : V.symbolic_value) (proj_ty : T.rty) :
-      V.abstract_shared_borrows option =
+  let reborrow_ashared proj_regions (sv : symbolic_value) (proj_ty : rty) :
+      abstract_shared_borrows option =
     if same_symbolic_id sv original_sv then
       match proj_ty with
-      | T.Ref (r, ref_ty, T.Shared) ->
+      | TRef (r, ref_ty, RShared) ->
           (* Projector over the shared value *)
-          let shared_asb = V.AsbProjReborrows (sv, ref_ty) in
+          let shared_asb = AsbProjReborrows (sv, ref_ty) in
           (* Check if the region is in the set of projected regions *)
           if region_in_set r proj_regions then
             (* In the set: we need to reborrow *)
             let bid = fresh_borrow () in
-            Some [ V.AsbBorrow bid; shared_asb ]
+            Some [ AsbBorrow bid; shared_asb ]
           else (* Not in the set: ignore *)
             Some [ shared_asb ]
       | _ -> raise (Failure "Unexpected")
@@ -322,31 +317,31 @@ let expand_symbolic_value_shared_borrow (config : C.config)
   (* Visitor to replace the projectors on borrows *)
   let obj =
     object (self)
-      inherit [_] C.map_eval_ctx as super
+      inherit [_] map_eval_ctx as super
 
-      method! visit_Symbolic env sv =
+      method! visit_VSymbolic env sv =
         if same_symbolic_id sv original_sv then
           let bid = fresh_borrow () in
-          V.Borrow (V.SharedBorrow bid)
-        else super#visit_Symbolic env sv
+          VBorrow (VSharedBorrow bid)
+        else super#visit_VSymbolic env sv
 
-      method! visit_Abs proj_regions abs =
+      method! visit_EAbs proj_regions abs =
         assert (Option.is_none proj_regions);
-        let proj_regions = Some abs.V.regions in
-        super#visit_Abs proj_regions abs
+        let proj_regions = Some abs.regions in
+        super#visit_EAbs proj_regions abs
 
       method! visit_AProjSharedBorrow proj_regions asb =
-        let expand_asb (asb : V.abstract_shared_borrow) :
-            V.abstract_shared_borrows =
+        let expand_asb (asb : abstract_shared_borrow) : abstract_shared_borrows
+            =
           match asb with
-          | V.AsbBorrow _ -> [ asb ]
-          | V.AsbProjReborrows (sv, proj_ty) -> (
+          | AsbBorrow _ -> [ asb ]
+          | AsbProjReborrows (sv, proj_ty) -> (
               match reborrow_ashared (Option.get proj_regions) sv proj_ty with
               | None -> [ asb ]
               | Some asb -> asb)
         in
         let asb = List.concat (List.map expand_asb asb) in
-        V.AProjSharedBorrow asb
+        AProjSharedBorrow asb
 
       (** We carefully updated {!visit_ASymbolic} so that {!visit_aproj} is called
           only on child projections (i.e., projections which appear in {!AEndedProjLoans}).
@@ -363,27 +358,27 @@ let expand_symbolic_value_shared_borrow (config : C.config)
       method! visit_ASymbolic proj_regions aproj =
         match aproj with
         | AEndedProjBorrows _ | AIgnoredProjBorrows ->
-            (* We ignore borrows *) V.ASymbolic aproj
+            (* We ignore borrows *) ASymbolic aproj
         | AProjLoans _ ->
             (* Loans are handled later *)
-            V.ASymbolic aproj
+            ASymbolic aproj
         | AProjBorrows (sv, proj_ty) -> (
             (* Check if we need to reborrow *)
             match reborrow_ashared (Option.get proj_regions) sv proj_ty with
             | None -> super#visit_ASymbolic proj_regions aproj
-            | Some asb -> V.ABorrow (V.AProjSharedBorrow asb))
+            | Some asb -> ABorrow (AProjSharedBorrow asb))
         | AEndedProjLoans _ ->
             (* Sanity check: make sure there is nothing to expand inside the
              * children projections *)
-            V.ASymbolic (self#visit_aproj proj_regions aproj)
+            ASymbolic (self#visit_aproj proj_regions aproj)
     end
   in
   (* Call the visitor *)
   let ctx = obj#visit_eval_ctx None ctx in
   (* Finally, replace the projectors on loans *)
   let bids = !borrows in
-  assert (not (V.BorrowId.Set.is_empty bids));
-  let see = V.SeSharedRef (bids, shared_sv) in
+  assert (not (BorrowId.Set.is_empty bids));
+  let see = SeSharedRef (bids, shared_sv) in
   let allow_reborrows = true in
   let ctx =
     apply_symbolic_expansion_to_avalues config allow_reborrows original_sv see
@@ -396,28 +391,26 @@ let expand_symbolic_value_shared_borrow (config : C.config)
     expr
 
 (** TODO: simplify and merge with the other expansion function *)
-let expand_symbolic_value_borrow (config : C.config)
-    (original_sv : V.symbolic_value) (original_sv_place : SA.mplace option)
-    (region : T.RegionId.id T.region) (ref_ty : T.rty) (rkind : T.ref_kind) :
-    cm_fun =
+let expand_symbolic_value_borrow (config : config)
+    (original_sv : symbolic_value) (original_sv_place : SA.mplace option)
+    (region : region) (ref_ty : rty) (rkind : ref_kind) : cm_fun =
  fun cf ctx ->
+  assert (region <> RErased);
   (* Check that we are allowed to expand the reference *)
   assert (not (region_in_set region ctx.ended_regions));
   (* Match on the reference kind *)
   match rkind with
-  | T.Mut ->
+  | RMut ->
       (* Simple case: simply create a fresh symbolic value and a fresh
        * borrow id *)
       let sv = mk_fresh_symbolic_value original_sv.sv_kind ref_ty in
-      let bid = C.fresh_borrow_id () in
-      let see = V.SeMutRef (bid, sv) in
+      let bid = fresh_borrow_id () in
+      let see = SeMutRef (bid, sv) in
       (* Expand the symbolic values - we simply perform a substitution (and
        * check that we perform exactly one substitution) *)
       let nv = symbolic_expansion_non_shared_borrow_to_value original_sv see in
       let at_most_once = true in
-      let ctx =
-        replace_symbolic_values at_most_once original_sv nv.V.value ctx
-      in
+      let ctx = replace_symbolic_values at_most_once original_sv nv.value ctx in
       (* Expand the symbolic avalues *)
       let allow_reborrows = true in
       let ctx =
@@ -429,7 +422,7 @@ let expand_symbolic_value_borrow (config : C.config)
       (* Update the synthesized program *)
       S.synthesize_symbolic_expansion_no_branching original_sv original_sv_place
         see expr
-  | T.Shared ->
+  | RShared ->
       expand_symbolic_value_shared_borrow config original_sv original_sv_place
         ref_ty cf ctx
 
@@ -449,9 +442,9 @@ let expand_symbolic_value_borrow (config : C.config)
     We need this continuation separately (i.e., we can't compose it with the
     continuations in [see_cf_l]) because we perform a join *before* calling it.
 *)
-let apply_branching_symbolic_expansions_non_borrow (config : C.config)
-    (sv : V.symbolic_value) (sv_place : SA.mplace option)
-    (see_cf_l : (V.symbolic_expansion option * st_cm_fun) list)
+let apply_branching_symbolic_expansions_non_borrow (config : config)
+    (sv : symbolic_value) (sv_place : SA.mplace option)
+    (see_cf_l : (symbolic_expansion option * st_cm_fun) list)
     (cf_after_join : st_m_fun) : m_fun =
  fun ctx ->
   assert (see_cf_l <> []);
@@ -492,25 +485,25 @@ let apply_branching_symbolic_expansions_non_borrow (config : C.config)
   let seel = List.map fst see_cf_l in
   S.synthesize_symbolic_expansion sv sv_place seel subterms
 
-let expand_symbolic_bool (config : C.config) (sv : V.symbolic_value)
+let expand_symbolic_bool (config : config) (sv : symbolic_value)
     (sv_place : SA.mplace option) (cf_true : st_cm_fun) (cf_false : st_cm_fun)
     (cf_after_join : st_m_fun) : m_fun =
  fun ctx ->
   (* Compute the expanded value *)
   let original_sv = sv in
   let original_sv_place = sv_place in
-  let rty = original_sv.V.sv_ty in
-  assert (rty = T.Literal PV.Bool);
+  let rty = original_sv.sv_ty in
+  assert (rty = TLiteral TBool);
   (* Expand the symbolic value to true or false and continue execution *)
-  let see_true = V.SeLiteral (PV.Bool true) in
-  let see_false = V.SeLiteral (PV.Bool false) in
+  let see_true = SeLiteral (VBool true) in
+  let see_false = SeLiteral (VBool false) in
   let seel = [ (Some see_true, cf_true); (Some see_false, cf_false) ] in
   (* Apply the symbolic expansion (this also outputs the updated symbolic AST) *)
   apply_branching_symbolic_expansions_non_borrow config original_sv
     original_sv_place seel cf_after_join ctx
 
-let expand_symbolic_value_no_branching (config : C.config)
-    (sv : V.symbolic_value) (sv_place : SA.mplace option) : cm_fun =
+let expand_symbolic_value_no_branching (config : config) (sv : symbolic_value)
+    (sv_place : SA.mplace option) : cm_fun =
  fun cf ctx ->
   (* Debug *)
   log#ldebug
@@ -522,12 +515,12 @@ let expand_symbolic_value_no_branching (config : C.config)
    * fresh symbolic values in the context (which thus gets updated) *)
   let original_sv = sv in
   let original_sv_place = sv_place in
-  let rty = original_sv.V.sv_ty in
+  let rty = original_sv.sv_ty in
   let cc : cm_fun =
    fun cf ctx ->
     match rty with
     (* ADTs *)
-    | T.Adt (adt_id, generics) ->
+    | TAdt (adt_id, generics) ->
         (* Compute the expanded value *)
         let allow_branching = false in
         let seel =
@@ -546,14 +539,14 @@ let expand_symbolic_value_no_branching (config : C.config)
         S.synthesize_symbolic_expansion_no_branching original_sv
           original_sv_place see expr
     (* Borrows *)
-    | T.Ref (region, ref_ty, rkind) ->
+    | TRef (region, ref_ty, rkind) ->
         expand_symbolic_value_borrow config original_sv original_sv_place region
           ref_ty rkind cf ctx
     | _ ->
         raise
           (Failure
              ("expand_symbolic_value_no_branching: unexpected type: "
-            ^ T.show_rty rty))
+            ^ show_rty rty))
   in
   (* Debug *)
   let cc =
@@ -565,12 +558,12 @@ let expand_symbolic_value_no_branching (config : C.config)
             ^ "\n\n- original context:\n" ^ eval_ctx_to_string ctx0
             ^ "\n\n- new context:\n" ^ eval_ctx_to_string ctx ^ "\n"));
         (* Sanity check: the symbolic value has disappeared *)
-        assert (not (symbolic_value_id_in_ctx original_sv.V.sv_id ctx)))
+        assert (not (symbolic_value_id_in_ctx original_sv.sv_id ctx)))
   in
   (* Continue *)
   cc cf ctx
 
-let expand_symbolic_adt (config : C.config) (sv : V.symbolic_value)
+let expand_symbolic_adt (config : config) (sv : symbolic_value)
     (sv_place : SA.mplace option) (cf_branches : st_cm_fun)
     (cf_after_join : st_m_fun) : m_fun =
  fun ctx ->
@@ -580,11 +573,11 @@ let expand_symbolic_adt (config : C.config) (sv : V.symbolic_value)
    * fresh symbolic values in the context (which thus gets updated) *)
   let original_sv = sv in
   let original_sv_place = sv_place in
-  let rty = original_sv.V.sv_ty in
+  let rty = original_sv.sv_ty in
   (* Execute *)
   match rty with
   (* ADTs *)
-  | T.Adt (adt_id, generics) ->
+  | TAdt (adt_id, generics) ->
       let allow_branching = true in
       (* Compute the expanded value *)
       let seel =
@@ -596,15 +589,14 @@ let expand_symbolic_adt (config : C.config) (sv : V.symbolic_value)
       apply_branching_symbolic_expansions_non_borrow config original_sv
         original_sv_place seel cf_after_join ctx
   | _ ->
-      raise
-        (Failure ("expand_symbolic_adt: unexpected type: " ^ T.show_rty rty))
+      raise (Failure ("expand_symbolic_adt: unexpected type: " ^ show_rty rty))
 
-let expand_symbolic_int (config : C.config) (sv : V.symbolic_value)
-    (sv_place : SA.mplace option) (int_type : T.integer_type)
-    (tgts : (V.scalar_value * st_cm_fun) list) (otherwise : st_cm_fun)
+let expand_symbolic_int (config : config) (sv : symbolic_value)
+    (sv_place : SA.mplace option) (int_type : integer_type)
+    (tgts : (scalar_value * st_cm_fun) list) (otherwise : st_cm_fun)
     (cf_after_join : st_m_fun) : m_fun =
   (* Sanity check *)
-  assert (sv.V.sv_ty = T.Literal (PV.Integer int_type));
+  assert (sv.sv_ty = TLiteral (TInteger int_type));
   (* For all the branches of the switch, we expand the symbolic value
    * to the value given by the branch and execute the branch statement.
    * For the otherwise branch, we leave the symbolic value as it is
@@ -615,7 +607,7 @@ let expand_symbolic_int (config : C.config) (sv : V.symbolic_value)
    * (optional expansion, statement to execute)
    *)
   let seel =
-    List.map (fun (v, cf) -> (Some (V.SeLiteral (PV.Scalar v)), cf)) tgts
+    List.map (fun (v, cf) -> (Some (SeLiteral (VScalar v)), cf)) tgts
   in
   let seel = List.append seel [ (None, otherwise) ] in
   (* Then expand and evaluate - this generates the proper symbolic AST *)
@@ -630,15 +622,15 @@ let expand_symbolic_int (config : C.config) (sv : V.symbolic_value)
     an enumeration with strictly more than one variant, a slice, etc.) or if
     we need to expand a recursive type (because this leads to looping).
  *)
-let greedy_expand_symbolics_with_borrows (config : C.config) : cm_fun =
+let greedy_expand_symbolics_with_borrows (config : config) : cm_fun =
  fun cf ctx ->
   (* The visitor object, to look for symbolic values in the concrete environment *)
   let obj =
     object
-      inherit [_] C.iter_eval_ctx
+      inherit [_] iter_eval_ctx
 
-      method! visit_Symbolic _ sv =
-        if ty_has_borrows ctx.type_context.type_infos sv.V.sv_ty then
+      method! visit_VSymbolic _ sv =
+        if ty_has_borrows ctx.type_context.type_infos sv.sv_ty then
           raise (FoundSymbolicValue sv)
         else ()
 
@@ -662,42 +654,41 @@ let greedy_expand_symbolics_with_borrows (config : C.config) : cm_fun =
           ("greedy_expand_symbolics_with_borrows: about to expand: "
           ^ symbolic_value_to_string ctx sv));
       let cc : cm_fun =
-        match sv.V.sv_ty with
-        | T.Adt (AdtId def_id, _) ->
+        match sv.sv_ty with
+        | TAdt (TAdtId def_id, _) ->
             (* {!expand_symbolic_value_no_branching} checks if there are branchings,
              * but we prefer to also check it here - this leads to cleaner messages
              * and debugging *)
-            let def = C.ctx_lookup_type_decl ctx def_id in
+            let def = ctx_lookup_type_decl ctx def_id in
             (match def.kind with
-            | T.Struct _ | T.Enum ([] | [ _ ]) -> ()
-            | T.Enum (_ :: _) ->
+            | Struct _ | Enum ([] | [ _ ]) -> ()
+            | Enum (_ :: _) ->
                 raise
                   (Failure
                      ("Attempted to greedily expand a symbolic enumeration \
                        with > 1 variants (option \
                        [greedy_expand_symbolics_with_borrows] of [config]): "
-                     ^ Print.name_to_string def.name))
-            | T.Opaque ->
+                     ^ name_to_string ctx def.name))
+            | Opaque ->
                 raise (Failure "Attempted to greedily expand an opaque type"));
             (* Also, we need to check if the definition is recursive *)
-            if C.ctx_type_decl_is_rec ctx def_id then
+            if ctx_type_decl_is_rec ctx def_id then
               raise
                 (Failure
                    ("Attempted to greedily expand a recursive definition \
                      (option [greedy_expand_symbolics_with_borrows] of \
                      [config]): "
-                   ^ Print.name_to_string def.name))
+                   ^ name_to_string ctx def.name))
             else expand_symbolic_value_no_branching config sv None
-        | T.Adt ((Tuple | Assumed Box), _) | T.Ref (_, _, _) ->
+        | TAdt ((TTuple | TAssumed TBox), _) | TRef (_, _, _) ->
             (* Ok *)
             expand_symbolic_value_no_branching config sv None
-        | T.Adt (Assumed (Array | Slice | Str), _) ->
+        | TAdt (TAssumed (TArray | TSlice | TStr), _) ->
             (* We can't expand those *)
             raise
               (Failure
                  "Attempted to greedily expand an ADT which can't be expanded ")
-        | T.TypeVar _ | T.Literal _ | Never | T.TraitType _ | T.Arrow _
-        | T.RawPtr _ ->
+        | TVar _ | TLiteral _ | TNever | TTraitType _ | TArrow _ | TRawPtr _ ->
             raise (Failure "Unreachable")
       in
       (* Compose and continue *)
@@ -706,7 +697,7 @@ let greedy_expand_symbolics_with_borrows (config : C.config) : cm_fun =
   (* Apply *)
   expand cf ctx
 
-let greedy_expand_symbolic_values (config : C.config) : cm_fun =
+let greedy_expand_symbolic_values (config : config) : cm_fun =
  fun cf ctx ->
   if Config.greedy_expand_symbolics_with_borrows then (
     log#ldebug (lazy "greedy_expand_symbolic_values");
diff --git a/compiler/InterpreterExpansion.mli b/compiler/InterpreterExpansion.mli
index b9165ecb..4be1fd24 100644
--- a/compiler/InterpreterExpansion.mli
+++ b/compiler/InterpreterExpansion.mli
@@ -1,15 +1,7 @@
-module T = Types
-module PV = PrimitiveValues
-module V = Values
-module E = Expressions
-module C = Contexts
-module Subst = Substitute
-module L = Logging
-module Inv = Invariants
-module S = SynthesizeSymbolic
-module SA = SymbolicAst
+open Values
+open Contexts
 open Cps
-open InterpreterBorrows
+module SA = SymbolicAst
 
 type proj_kind = LoanProj | BorrowProj
 
@@ -20,15 +12,11 @@ type proj_kind = LoanProj | BorrowProj
     This function does *not* update the synthesis.
 *)
 val apply_symbolic_expansion_non_borrow :
-  C.config ->
-  V.symbolic_value ->
-  V.symbolic_expansion ->
-  C.eval_ctx ->
-  C.eval_ctx
+  config -> symbolic_value -> symbolic_expansion -> eval_ctx -> eval_ctx
 
 (** Expand a symhbolic value, without branching *)
 val expand_symbolic_value_no_branching :
-  C.config -> V.symbolic_value -> SA.mplace option -> cm_fun
+  config -> symbolic_value -> SA.mplace option -> cm_fun
 
 (** Expand a symbolic enumeration (leads to branching if the enumeration has
     more than one variant).
@@ -44,12 +32,7 @@ val expand_symbolic_value_no_branching :
       then call it).
  *)
 val expand_symbolic_adt :
-  C.config ->
-  V.symbolic_value ->
-  SA.mplace option ->
-  st_cm_fun ->
-  st_m_fun ->
-  m_fun
+  config -> symbolic_value -> SA.mplace option -> st_cm_fun -> st_m_fun -> m_fun
 
 (** Expand a symbolic boolean.
 
@@ -58,8 +41,8 @@ val expand_symbolic_adt :
     parameter (here, there are exactly two branches).
  *)
 val expand_symbolic_bool :
-  C.config ->
-  V.symbolic_value ->
+  config ->
+  symbolic_value ->
   SA.mplace option ->
   st_cm_fun ->
   st_cm_fun ->
@@ -86,16 +69,16 @@ val expand_symbolic_bool :
     switch. The continuation is thus for the execution *after* the switch.
  *)
 val expand_symbolic_int :
-  C.config ->
-  V.symbolic_value ->
+  config ->
+  symbolic_value ->
   SA.mplace option ->
-  T.integer_type ->
-  (V.scalar_value * st_cm_fun) list ->
+  integer_type ->
+  (scalar_value * st_cm_fun) list ->
   st_cm_fun ->
   st_m_fun ->
   m_fun
 
 (** If this mode is activated through the [config], greedily expand the symbolic
-    values which need to be expanded. See {!type:C.config} for more information.
+    values which need to be expanded. See {!type:config} for more information.
  *)
-val greedy_expand_symbolic_values : C.config -> cm_fun
+val greedy_expand_symbolic_values : config -> cm_fun
diff --git a/compiler/InterpreterExpressions.ml b/compiler/InterpreterExpressions.ml
index 245f3b77..cc0580be 100644
--- a/compiler/InterpreterExpressions.ml
+++ b/compiler/InterpreterExpressions.ml
@@ -1,25 +1,20 @@
-module T = Types
-module PV = PrimitiveValues
-module V = Values
-module LA = LlbcAst
+open Types
+open Values
+open LlbcAst
 open Scalars
-module E = Expressions
+open Expressions
 open Utils
-module C = Contexts
-module Subst = Substitute
-module Assoc = AssociatedTypes
-module L = Logging
+open Contexts
 open TypesUtils
 open ValuesUtils
-module Inv = Invariants
-module S = SynthesizeSymbolic
+open SynthesizeSymbolic
 open Cps
 open InterpreterUtils
 open InterpreterExpansion
 open InterpreterPaths
 
 (** The local logger *)
-let log = L.expressions_log
+let log = Logging.expressions_log
 
 (** As long as there are symbolic values at a given place (potentially in subvalues)
     which contain borrows and are primitively copyable, expand them.
@@ -29,8 +24,8 @@ let log = L.expressions_log
     Note that the place should have been prepared so that there are no remaining
     loans.
 *)
-let expand_primitively_copyable_at_place (config : C.config)
-    (access : access_kind) (p : E.place) : cm_fun =
+let expand_primitively_copyable_at_place (config : config)
+    (access : access_kind) (p : place) : cm_fun =
  fun cf ctx ->
   (* Small helper *)
   let rec expand : cm_fun =
@@ -43,8 +38,7 @@ let expand_primitively_copyable_at_place (config : C.config)
     | None -> cf ctx
     | Some sv ->
         let cc =
-          expand_symbolic_value_no_branching config sv
-            (Some (S.mk_mplace p ctx))
+          expand_symbolic_value_no_branching config sv (Some (mk_mplace p ctx))
         in
         comp cc expand cf ctx
   in
@@ -56,8 +50,8 @@ let expand_primitively_copyable_at_place (config : C.config)
     We also check that the value *doesn't contain bottoms or reserved
     borrows*.
  *)
-let read_place (access : access_kind) (p : E.place)
-    (cf : V.typed_value -> m_fun) : m_fun =
+let read_place (access : access_kind) (p : place) (cf : typed_value -> m_fun) :
+    m_fun =
  fun ctx ->
   let v = read_place access p ctx in
   (* Check that there are no bottoms in the value *)
@@ -67,9 +61,9 @@ let read_place (access : access_kind) (p : E.place)
   (* Call the continuation *)
   cf v ctx
 
-let access_rplace_reorganize_and_read (config : C.config)
-    (expand_prim_copy : bool) (access : access_kind) (p : E.place)
-    (cf : V.typed_value -> m_fun) : m_fun =
+let access_rplace_reorganize_and_read (config : config)
+    (expand_prim_copy : bool) (access : access_kind) (p : place)
+    (cf : typed_value -> m_fun) : m_fun =
  fun ctx ->
   (* Make sure we can evaluate the path *)
   let cc = update_ctx_along_read_place config access p in
@@ -87,31 +81,30 @@ let access_rplace_reorganize_and_read (config : C.config)
   (* Compose *)
   comp cc read_place cf ctx
 
-let access_rplace_reorganize (config : C.config) (expand_prim_copy : bool)
-    (access : access_kind) (p : E.place) : cm_fun =
+let access_rplace_reorganize (config : config) (expand_prim_copy : bool)
+    (access : access_kind) (p : place) : cm_fun =
  fun cf ctx ->
   access_rplace_reorganize_and_read config expand_prim_copy access p
     (fun _v -> cf)
     ctx
 
 (** Convert an operand constant operand value to a typed value *)
-let literal_to_typed_value (ty : PV.literal_type) (cv : V.literal) :
-    V.typed_value =
+let literal_to_typed_value (ty : literal_type) (cv : literal) : typed_value =
   (* Check the type while converting - we actually need some information
      * contained in the type *)
   log#ldebug
     (lazy
       ("literal_to_typed_value:" ^ "\n- cv: "
-      ^ Print.PrimitiveValues.literal_to_string cv));
+      ^ Print.Values.literal_to_string cv));
   match (ty, cv) with
   (* Scalar, boolean... *)
-  | PV.Bool, Bool v -> { V.value = V.Literal (Bool v); ty = T.Literal ty }
-  | Char, Char v -> { V.value = V.Literal (Char v); ty = T.Literal ty }
-  | Integer int_ty, PV.Scalar v ->
+  | TBool, VBool v -> { value = VLiteral (VBool v); ty = TLiteral ty }
+  | TChar, VChar v -> { value = VLiteral (VChar v); ty = TLiteral ty }
+  | TInteger int_ty, VScalar v ->
       (* Check the type and the ranges *)
       assert (int_ty = v.int_ty);
       assert (check_scalar_value_in_range v);
-      { V.value = V.Literal (PV.Scalar v); ty = T.Literal ty }
+      { value = VLiteral (VScalar v); ty = TLiteral ty }
   (* Remaining cases (invalid) *)
   | _, _ -> raise (Failure "Improperly typed constant value")
 
@@ -126,8 +119,8 @@ let literal_to_typed_value (ty : PV.literal_type) (cv : V.literal) :
     parameter to control this copy ([allow_adt_copy]). Note that here by ADT we
     mean the user-defined ADTs (not tuples or assumed types).
  *)
-let rec copy_value (allow_adt_copy : bool) (config : C.config)
-    (ctx : C.eval_ctx) (v : V.typed_value) : C.eval_ctx * V.typed_value =
+let rec copy_value (allow_adt_copy : bool) (config : config) (ctx : eval_ctx)
+    (v : typed_value) : eval_ctx * typed_value =
   log#ldebug
     (lazy
       ("copy_value: "
@@ -137,18 +130,18 @@ let rec copy_value (allow_adt_copy : bool) (config : C.config)
    * we reverted the changes: the result was less clear actually. In particular,
    * the fact that we have exhaustive matches below makes very obvious the cases
    * in which we need to fail *)
-  match v.V.value with
-  | V.Literal _ -> (ctx, v)
-  | V.Adt av ->
+  match v.value with
+  | VLiteral _ -> (ctx, v)
+  | VAdt av ->
       (* Sanity check *)
-      (match v.V.ty with
-      | T.Adt (T.Assumed T.Box, _) ->
+      (match v.ty with
+      | TAdt (TAssumed TBox, _) ->
           raise (Failure "Can't copy an assumed value other than Option")
-      | T.Adt (T.AdtId _, _) as ty ->
+      | TAdt (TAdtId _, _) as ty ->
           assert (allow_adt_copy || ty_is_primitively_copyable ty)
-      | T.Adt (T.Tuple, _) -> () (* Ok *)
-      | T.Adt
-          ( T.Assumed (Slice | T.Array),
+      | TAdt (TTuple, _) -> () (* Ok *)
+      | TAdt
+          ( TAssumed (TSlice | TArray),
             {
               regions = [];
               types = [ ty ];
@@ -162,33 +155,33 @@ let rec copy_value (allow_adt_copy : bool) (config : C.config)
           (copy_value allow_adt_copy config)
           ctx av.field_values
       in
-      (ctx, { v with V.value = V.Adt { av with field_values = fields } })
-  | V.Bottom -> raise (Failure "Can't copy ⊥")
-  | V.Borrow bc -> (
+      (ctx, { v with value = VAdt { av with field_values = fields } })
+  | VBottom -> raise (Failure "Can't copy ⊥")
+  | VBorrow bc -> (
       (* We can only copy shared borrows *)
       match bc with
-      | SharedBorrow bid ->
+      | VSharedBorrow bid ->
           (* We need to create a new borrow id for the copied borrow, and
            * update the context accordingly *)
-          let bid' = C.fresh_borrow_id () in
+          let bid' = fresh_borrow_id () in
           let ctx = InterpreterBorrows.reborrow_shared bid bid' ctx in
-          (ctx, { v with V.value = V.Borrow (SharedBorrow bid') })
-      | MutBorrow (_, _) -> raise (Failure "Can't copy a mutable borrow")
-      | V.ReservedMutBorrow _ ->
+          (ctx, { v with value = VBorrow (VSharedBorrow bid') })
+      | VMutBorrow (_, _) -> raise (Failure "Can't copy a mutable borrow")
+      | VReservedMutBorrow _ ->
           raise (Failure "Can't copy a reserved mut borrow"))
-  | V.Loan lc -> (
+  | VLoan lc -> (
       (* We can only copy shared loans *)
       match lc with
-      | V.MutLoan _ -> raise (Failure "Can't copy a mutable loan")
-      | V.SharedLoan (_, sv) ->
+      | VMutLoan _ -> raise (Failure "Can't copy a mutable loan")
+      | VSharedLoan (_, sv) ->
           (* We don't copy the shared loan: only the shared value inside *)
           copy_value allow_adt_copy config ctx sv)
-  | V.Symbolic sp ->
+  | VSymbolic sp ->
       (* We can copy only if the type is "primitively" copyable.
        * Note that in the general case, copy is a trait: copying values
        * thus requires calling the proper function. Here, we copy values
        * for very simple types such as integers, shared borrows, etc. *)
-      assert (ty_is_primitively_copyable (Subst.erase_regions sp.V.sv_ty));
+      assert (ty_is_primitively_copyable (Substitute.erase_regions sp.sv_ty));
       (* If the type is copyable, we simply return the current value. Side
        * remark: what is important to look at when copying symbolic values
        * is symbolic expansion. The important subcase is the expansion of shared
@@ -233,22 +226,21 @@ let rec copy_value (allow_adt_copy : bool) (config : C.config)
     what we do in the formalization (because we don't enforce the same constraints
     as MIR in the formalization).
  *)
-let prepare_eval_operand_reorganize (config : C.config) (op : E.operand) :
-    cm_fun =
+let prepare_eval_operand_reorganize (config : config) (op : operand) : cm_fun =
  fun cf ctx ->
   let prepare : cm_fun =
    fun cf ctx ->
     match op with
-    | E.Constant _ ->
+    | Constant _ ->
         (* No need to reorganize the context *)
         cf ctx
-    | E.Copy p ->
+    | Copy p ->
         (* Access the value *)
         let access = Read in
         (* Expand the symbolic values, if necessary *)
         let expand_prim_copy = true in
         access_rplace_reorganize config expand_prim_copy access p cf ctx
-    | E.Move p ->
+    | Move p ->
         (* Access the value *)
         let access = Move in
         let expand_prim_copy = false in
@@ -258,8 +250,8 @@ let prepare_eval_operand_reorganize (config : C.config) (op : E.operand) :
   prepare cf ctx
 
 (** Evaluate an operand, without reorganizing the context before *)
-let eval_operand_no_reorganize (config : C.config) (op : E.operand)
-    (cf : V.typed_value -> m_fun) : m_fun =
+let eval_operand_no_reorganize (config : config) (op : operand)
+    (cf : typed_value -> m_fun) : m_fun =
  fun ctx ->
   (* Debug *)
   log#ldebug
@@ -268,14 +260,14 @@ let eval_operand_no_reorganize (config : C.config) (op : E.operand)
      ^ "\n- ctx:\n" ^ eval_ctx_to_string ctx ^ "\n"));
   (* Evaluate *)
   match op with
-  | E.Constant cv -> (
+  | Constant cv -> (
       match cv.value with
-      | E.CLiteral lit ->
-          cf (literal_to_typed_value (TypesUtils.ty_as_literal cv.ty) lit) ctx
-      | E.CTraitConst (trait_ref, generics, const_name) -> (
-          assert (generics = TypesUtils.mk_empty_generic_args);
+      | CLiteral lit ->
+          cf (literal_to_typed_value (ty_as_literal cv.ty) lit) ctx
+      | CTraitConst (trait_ref, generics, const_name) -> (
+          assert (generics = empty_generic_args);
           match trait_ref.trait_id with
-          | T.TraitImpl _ ->
+          | TraitImpl _ ->
               (* This shouldn't happen: if we refer to a concrete implementation, we
                  should directly refer to the top-level constant *)
               raise (Failure "Unreachable")
@@ -285,14 +277,13 @@ let eval_operand_no_reorganize (config : C.config) (op : E.operand)
               let ctx0 = ctx in
               (* Lookup the trait declaration to retrieve the type of the symbolic value *)
               let trait_decl =
-                C.ctx_lookup_trait_decl ctx
-                  trait_ref.trait_decl_ref.trait_decl_id
+                ctx_lookup_trait_decl ctx trait_ref.trait_decl_ref.trait_decl_id
               in
               let _, (ty, _) =
                 List.find (fun (name, _) -> name = const_name) trait_decl.consts
               in
               (* Introduce a fresh symbolic value *)
-              let v = mk_fresh_symbolic_typed_value_from_ety V.TraitConst ty in
+              let v = mk_fresh_symbolic_typed_value TraitConst ty in
               (* Continue the evaluation *)
               let e = cf v ctx in
               (* We have to wrap the generated expression *)
@@ -304,13 +295,13 @@ let eval_operand_no_reorganize (config : C.config) (op : E.operand)
                        ( ctx0,
                          None,
                          value_as_symbolic v.value,
-                         SymbolicAst.TraitConstValue
+                         SymbolicAst.VaTraitConstValue
                            (trait_ref, generics, const_name),
                          e ))))
-      | E.CVar vid -> (
+      | CVar vid -> (
           let ctx0 = ctx in
           (* Lookup the const generic value *)
-          let cv = C.ctx_lookup_const_generic_value ctx vid in
+          let cv = ctx_lookup_const_generic_value ctx vid in
           (* Copy the value *)
           let allow_adt_copy = false in
           let ctx, v = copy_value allow_adt_copy config ctx cv in
@@ -322,17 +313,17 @@ let eval_operand_no_reorganize (config : C.config) (op : E.operand)
           | Some e ->
               (* If we are synthesizing a symbolic AST, it means that we are in symbolic
                  mode: the value of the const generic is necessarily symbolic. *)
-              assert (is_symbolic cv.V.value);
+              assert (is_symbolic cv.value);
               (* *)
               Some
                 (SymbolicAst.IntroSymbolic
                    ( ctx0,
                      None,
                      value_as_symbolic v.value,
-                     SymbolicAst.ConstGenericValue vid,
+                     SymbolicAst.VaCgValue vid,
                      e )))
-      | E.CFnPtr _ -> raise (Failure "TODO"))
-  | E.Copy p ->
+      | CFnPtr _ -> raise (Failure "TODO"))
+  | Copy p ->
       (* Access the value *)
       let access = Read in
       let cc = read_place access p in
@@ -353,7 +344,7 @@ let eval_operand_no_reorganize (config : C.config) (op : E.operand)
       in
       (* Compose and apply *)
       comp cc copy cf ctx
-  | E.Move p ->
+  | Move p ->
       (* Access the value *)
       let access = Move in
       let cc = read_place access p in
@@ -362,15 +353,15 @@ let eval_operand_no_reorganize (config : C.config) (op : E.operand)
        fun ctx ->
         (* Check that there are no bottoms in the value we are about to move *)
         assert (not (bottom_in_value ctx.ended_regions v));
-        let bottom : V.typed_value = { V.value = Bottom; ty = v.ty } in
+        let bottom : typed_value = { value = VBottom; ty = v.ty } in
         let ctx = write_place access p bottom ctx in
         cf v ctx
       in
       (* Compose and apply *)
       comp cc move cf ctx
 
-let eval_operand (config : C.config) (op : E.operand)
-    (cf : V.typed_value -> m_fun) : m_fun =
+let eval_operand (config : config) (op : operand) (cf : typed_value -> m_fun) :
+    m_fun =
  fun ctx ->
   (* Debug *)
   log#ldebug
@@ -387,13 +378,13 @@ let eval_operand (config : C.config) (op : E.operand)
 
     See [prepare_eval_operand_reorganize].
  *)
-let prepare_eval_operands_reorganize (config : C.config) (ops : E.operand list)
-    : cm_fun =
+let prepare_eval_operands_reorganize (config : config) (ops : operand list) :
+    cm_fun =
   fold_left_apply_continuation (prepare_eval_operand_reorganize config) ops
 
 (** Evaluate several operands. *)
-let eval_operands (config : C.config) (ops : E.operand list)
-    (cf : V.typed_value list -> m_fun) : m_fun =
+let eval_operands (config : config) (ops : operand list)
+    (cf : typed_value list -> m_fun) : m_fun =
  fun ctx ->
   (* Prepare the operands *)
   let prepare = prepare_eval_operands_reorganize config ops in
@@ -404,8 +395,8 @@ let eval_operands (config : C.config) (ops : E.operand list)
   (* Compose and apply *)
   comp prepare eval cf ctx
 
-let eval_two_operands (config : C.config) (op1 : E.operand) (op2 : E.operand)
-    (cf : V.typed_value * V.typed_value -> m_fun) : m_fun =
+let eval_two_operands (config : config) (op1 : operand) (op2 : operand)
+    (cf : typed_value * typed_value -> m_fun) : m_fun =
   let eval_op = eval_operands config [ op1; op2 ] in
   let use_res cf res =
     match res with
@@ -414,73 +405,73 @@ let eval_two_operands (config : C.config) (op1 : E.operand) (op2 : E.operand)
   in
   comp eval_op use_res cf
 
-let eval_unary_op_concrete (config : C.config) (unop : E.unop) (op : E.operand)
-    (cf : (V.typed_value, eval_error) result -> m_fun) : m_fun =
+let eval_unary_op_concrete (config : config) (unop : unop) (op : operand)
+    (cf : (typed_value, eval_error) result -> m_fun) : m_fun =
   (* Evaluate the operand *)
   let eval_op = eval_operand config op in
   (* Apply the unop *)
-  let apply cf (v : V.typed_value) : m_fun =
-    match (unop, v.V.value) with
-    | E.Not, V.Literal (Bool b) ->
-        cf (Ok { v with V.value = V.Literal (Bool (not b)) })
-    | E.Neg, V.Literal (PV.Scalar sv) -> (
-        let i = Z.neg sv.PV.value in
+  let apply cf (v : typed_value) : m_fun =
+    match (unop, v.value) with
+    | Not, VLiteral (VBool b) ->
+        cf (Ok { v with value = VLiteral (VBool (not b)) })
+    | Neg, VLiteral (VScalar sv) -> (
+        let i = Z.neg sv.value in
         match mk_scalar sv.int_ty i with
         | Error _ -> cf (Error EPanic)
-        | Ok sv -> cf (Ok { v with V.value = V.Literal (PV.Scalar sv) }))
-    | E.Cast (E.CastInteger (src_ty, tgt_ty)), V.Literal (PV.Scalar sv) -> (
+        | Ok sv -> cf (Ok { v with value = VLiteral (VScalar sv) }))
+    | Cast (CastInteger (src_ty, tgt_ty)), VLiteral (VScalar sv) -> (
         assert (src_ty = sv.int_ty);
-        let i = sv.PV.value in
+        let i = sv.value in
         match mk_scalar tgt_ty i with
         | Error _ -> cf (Error EPanic)
         | Ok sv ->
-            let ty = T.Literal (Integer tgt_ty) in
-            let value = V.Literal (PV.Scalar sv) in
-            cf (Ok { V.ty; value }))
+            let ty = TLiteral (TInteger tgt_ty) in
+            let value = VLiteral (VScalar sv) in
+            cf (Ok { ty; value }))
     | _ -> raise (Failure "Invalid input for unop")
   in
   comp eval_op apply cf
 
-let eval_unary_op_symbolic (config : C.config) (unop : E.unop) (op : E.operand)
-    (cf : (V.typed_value, eval_error) result -> m_fun) : m_fun =
+let eval_unary_op_symbolic (config : config) (unop : unop) (op : operand)
+    (cf : (typed_value, eval_error) result -> m_fun) : m_fun =
  fun ctx ->
   (* Evaluate the operand *)
   let eval_op = eval_operand config op in
   (* Generate a fresh symbolic value to store the result *)
-  let apply cf (v : V.typed_value) : m_fun =
+  let apply cf (v : typed_value) : m_fun =
    fun ctx ->
-    let res_sv_id = C.fresh_symbolic_value_id () in
+    let res_sv_id = fresh_symbolic_value_id () in
     let res_sv_ty =
-      match (unop, v.V.ty) with
-      | E.Not, (T.Literal Bool as lty) -> lty
-      | E.Neg, (T.Literal (Integer _) as lty) -> lty
-      | E.Cast (E.CastInteger (_, tgt_ty)), _ -> T.Literal (Integer tgt_ty)
+      match (unop, v.ty) with
+      | Not, (TLiteral TBool as lty) -> lty
+      | Neg, (TLiteral (TInteger _) as lty) -> lty
+      | Cast (CastInteger (_, tgt_ty)), _ -> TLiteral (TInteger tgt_ty)
       | _ -> raise (Failure "Invalid input for unop")
     in
     let res_sv =
-      { V.sv_kind = V.FunCallRet; V.sv_id = res_sv_id; sv_ty = res_sv_ty }
+      { sv_kind = FunCallRet; sv_id = res_sv_id; sv_ty = res_sv_ty }
     in
     (* Call the continuation *)
     let expr = cf (Ok (mk_typed_value_from_symbolic_value res_sv)) ctx in
     (* Synthesize the symbolic AST *)
-    S.synthesize_unary_op ctx unop v
-      (S.mk_opt_place_from_op op ctx)
+    synthesize_unary_op ctx unop v
+      (mk_opt_place_from_op op ctx)
       res_sv None expr
   in
   (* Compose and apply *)
   comp eval_op apply cf ctx
 
-let eval_unary_op (config : C.config) (unop : E.unop) (op : E.operand)
-    (cf : (V.typed_value, eval_error) result -> m_fun) : m_fun =
+let eval_unary_op (config : config) (unop : unop) (op : operand)
+    (cf : (typed_value, eval_error) result -> m_fun) : m_fun =
   match config.mode with
-  | C.ConcreteMode -> eval_unary_op_concrete config unop op cf
-  | C.SymbolicMode -> eval_unary_op_symbolic config unop op cf
+  | ConcreteMode -> eval_unary_op_concrete config unop op cf
+  | SymbolicMode -> eval_unary_op_symbolic config unop op cf
 
 (** Small helper for [eval_binary_op_concrete]: computes the result of applying
     the binop *after* the operands have been successfully evaluated
  *)
-let eval_binary_op_concrete_compute (binop : E.binop) (v1 : V.typed_value)
-    (v2 : V.typed_value) : (V.typed_value, eval_error) result =
+let eval_binary_op_concrete_compute (binop : binop) (v1 : typed_value)
+    (v2 : typed_value) : (typed_value, eval_error) result =
   (* Equality check binops (Eq, Ne) accept values from a wide variety of types.
    * The remaining binops only operate on scalars. *)
   if binop = Eq || binop = Ne then (
@@ -489,53 +480,52 @@ let eval_binary_op_concrete_compute (binop : E.binop) (v1 : V.typed_value)
     (* Equality/inequality check is primitive only for a subset of types *)
     assert (ty_is_primitively_copyable v1.ty);
     let b = v1 = v2 in
-    Ok { V.value = V.Literal (Bool b); ty = T.Literal Bool })
+    Ok { value = VLiteral (VBool b); ty = TLiteral TBool })
   else
     (* For the non-equality operations, the input values are necessarily scalars *)
-    match (v1.V.value, v2.V.value) with
-    | V.Literal (PV.Scalar sv1), V.Literal (PV.Scalar sv2) -> (
+    match (v1.value, v2.value) with
+    | VLiteral (VScalar sv1), VLiteral (VScalar sv2) -> (
         (* There are binops which require the two operands to have the same
            type, and binops for which it is not the case.
            There are also binops which return booleans, and binops which
            return integers.
         *)
         match binop with
-        | E.Lt | E.Le | E.Ge | E.Gt ->
+        | Lt | Le | Ge | Gt ->
             (* The two operands must have the same type and the result is a boolean *)
             assert (sv1.int_ty = sv2.int_ty);
             let b =
               match binop with
-              | E.Lt -> Z.lt sv1.PV.value sv2.PV.value
-              | E.Le -> Z.leq sv1.PV.value sv2.PV.value
-              | E.Ge -> Z.geq sv1.PV.value sv2.PV.value
-              | E.Gt -> Z.gt sv1.PV.value sv2.PV.value
-              | E.Div | E.Rem | E.Add | E.Sub | E.Mul | E.BitXor | E.BitAnd
-              | E.BitOr | E.Shl | E.Shr | E.Ne | E.Eq ->
+              | Lt -> Z.lt sv1.value sv2.value
+              | Le -> Z.leq sv1.value sv2.value
+              | Ge -> Z.geq sv1.value sv2.value
+              | Gt -> Z.gt sv1.value sv2.value
+              | Div | Rem | Add | Sub | Mul | BitXor | BitAnd | BitOr | Shl
+              | Shr | Ne | Eq ->
                   raise (Failure "Unreachable")
             in
             Ok
-              ({ V.value = V.Literal (Bool b); ty = T.Literal Bool }
-                : V.typed_value)
-        | E.Div | E.Rem | E.Add | E.Sub | E.Mul | E.BitXor | E.BitAnd | E.BitOr
-          -> (
+              ({ value = VLiteral (VBool b); ty = TLiteral TBool }
+                : typed_value)
+        | Div | Rem | Add | Sub | Mul | BitXor | BitAnd | BitOr -> (
             (* The two operands must have the same type and the result is an integer *)
             assert (sv1.int_ty = sv2.int_ty);
             let res =
               match binop with
-              | E.Div ->
-                  if sv2.PV.value = Z.zero then Error ()
-                  else mk_scalar sv1.int_ty (Z.div sv1.PV.value sv2.PV.value)
-              | E.Rem ->
+              | Div ->
+                  if sv2.value = Z.zero then Error ()
+                  else mk_scalar sv1.int_ty (Z.div sv1.value sv2.value)
+              | Rem ->
                   (* See [https://github.com/ocaml/Zarith/blob/master/z.mli] *)
-                  if sv2.PV.value = Z.zero then Error ()
-                  else mk_scalar sv1.int_ty (Z.rem sv1.PV.value sv2.PV.value)
-              | E.Add -> mk_scalar sv1.int_ty (Z.add sv1.PV.value sv2.PV.value)
-              | E.Sub -> mk_scalar sv1.int_ty (Z.sub sv1.PV.value sv2.PV.value)
-              | E.Mul -> mk_scalar sv1.int_ty (Z.mul sv1.PV.value sv2.PV.value)
-              | E.BitXor -> raise Unimplemented
-              | E.BitAnd -> raise Unimplemented
-              | E.BitOr -> raise Unimplemented
-              | E.Lt | E.Le | E.Ge | E.Gt | E.Shl | E.Shr | E.Ne | E.Eq ->
+                  if sv2.value = Z.zero then Error ()
+                  else mk_scalar sv1.int_ty (Z.rem sv1.value sv2.value)
+              | Add -> mk_scalar sv1.int_ty (Z.add sv1.value sv2.value)
+              | Sub -> mk_scalar sv1.int_ty (Z.sub sv1.value sv2.value)
+              | Mul -> mk_scalar sv1.int_ty (Z.mul sv1.value sv2.value)
+              | BitXor -> raise Unimplemented
+              | BitAnd -> raise Unimplemented
+              | BitOr -> raise Unimplemented
+              | Lt | Le | Ge | Gt | Shl | Shr | Ne | Eq ->
                   raise (Failure "Unreachable")
             in
             match res with
@@ -543,97 +533,93 @@ let eval_binary_op_concrete_compute (binop : E.binop) (v1 : V.typed_value)
             | Ok sv ->
                 Ok
                   {
-                    V.value = V.Literal (PV.Scalar sv);
-                    ty = T.Literal (Integer sv1.int_ty);
+                    value = VLiteral (VScalar sv);
+                    ty = TLiteral (TInteger sv1.int_ty);
                   })
-        | E.Shl | E.Shr -> raise Unimplemented
-        | E.Ne | E.Eq -> raise (Failure "Unreachable"))
+        | Shl | Shr -> raise Unimplemented
+        | Ne | Eq -> raise (Failure "Unreachable"))
     | _ -> raise (Failure "Invalid inputs for binop")
 
-let eval_binary_op_concrete (config : C.config) (binop : E.binop)
-    (op1 : E.operand) (op2 : E.operand)
-    (cf : (V.typed_value, eval_error) result -> m_fun) : m_fun =
+let eval_binary_op_concrete (config : config) (binop : binop) (op1 : operand)
+    (op2 : operand) (cf : (typed_value, eval_error) result -> m_fun) : m_fun =
   (* Evaluate the operands *)
   let eval_ops = eval_two_operands config op1 op2 in
   (* Compute the result of the binop *)
-  let compute cf (res : V.typed_value * V.typed_value) =
+  let compute cf (res : typed_value * typed_value) =
     let v1, v2 = res in
     cf (eval_binary_op_concrete_compute binop v1 v2)
   in
   (* Compose and apply *)
   comp eval_ops compute cf
 
-let eval_binary_op_symbolic (config : C.config) (binop : E.binop)
-    (op1 : E.operand) (op2 : E.operand)
-    (cf : (V.typed_value, eval_error) result -> m_fun) : m_fun =
+let eval_binary_op_symbolic (config : config) (binop : binop) (op1 : operand)
+    (op2 : operand) (cf : (typed_value, eval_error) result -> m_fun) : m_fun =
  fun ctx ->
   (* Evaluate the operands *)
   let eval_ops = eval_two_operands config op1 op2 in
   (* Compute the result of applying the binop *)
-  let compute cf ((v1, v2) : V.typed_value * V.typed_value) : m_fun =
+  let compute cf ((v1, v2) : typed_value * typed_value) : m_fun =
    fun ctx ->
     (* Generate a fresh symbolic value to store the result *)
-    let res_sv_id = C.fresh_symbolic_value_id () in
+    let res_sv_id = fresh_symbolic_value_id () in
     let res_sv_ty =
       if binop = Eq || binop = Ne then (
         (* Equality operations *)
         assert (v1.ty = v2.ty);
         (* Equality/inequality check is primitive only for a subset of types *)
         assert (ty_is_primitively_copyable v1.ty);
-        T.Literal Bool)
+        TLiteral TBool)
       else
         (* Other operations: input types are integers *)
-        match (v1.V.ty, v2.V.ty) with
-        | T.Literal (Integer int_ty1), T.Literal (Integer int_ty2) -> (
+        match (v1.ty, v2.ty) with
+        | TLiteral (TInteger int_ty1), TLiteral (TInteger int_ty2) -> (
             match binop with
-            | E.Lt | E.Le | E.Ge | E.Gt ->
+            | Lt | Le | Ge | Gt ->
                 assert (int_ty1 = int_ty2);
-                T.Literal Bool
-            | E.Div | E.Rem | E.Add | E.Sub | E.Mul | E.BitXor | E.BitAnd
-            | E.BitOr ->
+                TLiteral TBool
+            | Div | Rem | Add | Sub | Mul | BitXor | BitAnd | BitOr ->
                 assert (int_ty1 = int_ty2);
-                T.Literal (Integer int_ty1)
-            | E.Shl | E.Shr -> raise Unimplemented
-            | E.Ne | E.Eq -> raise (Failure "Unreachable"))
+                TLiteral (TInteger int_ty1)
+            | Shl | Shr -> raise Unimplemented
+            | Ne | Eq -> raise (Failure "Unreachable"))
         | _ -> raise (Failure "Invalid inputs for binop")
     in
     let res_sv =
-      { V.sv_kind = V.FunCallRet; V.sv_id = res_sv_id; sv_ty = res_sv_ty }
+      { sv_kind = FunCallRet; sv_id = res_sv_id; sv_ty = res_sv_ty }
     in
     (* Call the continuattion *)
     let v = mk_typed_value_from_symbolic_value res_sv in
     let expr = cf (Ok v) ctx in
     (* Synthesize the symbolic AST *)
-    let p1 = S.mk_opt_place_from_op op1 ctx in
-    let p2 = S.mk_opt_place_from_op op2 ctx in
-    S.synthesize_binary_op ctx binop v1 p1 v2 p2 res_sv None expr
+    let p1 = mk_opt_place_from_op op1 ctx in
+    let p2 = mk_opt_place_from_op op2 ctx in
+    synthesize_binary_op ctx binop v1 p1 v2 p2 res_sv None expr
   in
   (* Compose and apply *)
   comp eval_ops compute cf ctx
 
-let eval_binary_op (config : C.config) (binop : E.binop) (op1 : E.operand)
-    (op2 : E.operand) (cf : (V.typed_value, eval_error) result -> m_fun) : m_fun
-    =
+let eval_binary_op (config : config) (binop : binop) (op1 : operand)
+    (op2 : operand) (cf : (typed_value, eval_error) result -> m_fun) : m_fun =
   match config.mode with
-  | C.ConcreteMode -> eval_binary_op_concrete config binop op1 op2 cf
-  | C.SymbolicMode -> eval_binary_op_symbolic config binop op1 op2 cf
+  | ConcreteMode -> eval_binary_op_concrete config binop op1 op2 cf
+  | SymbolicMode -> eval_binary_op_symbolic config binop op1 op2 cf
 
-let eval_rvalue_ref (config : C.config) (p : E.place) (bkind : E.borrow_kind)
-    (cf : V.typed_value -> m_fun) : m_fun =
+let eval_rvalue_ref (config : config) (p : place) (bkind : borrow_kind)
+    (cf : typed_value -> m_fun) : m_fun =
  fun ctx ->
   match bkind with
-  | E.Shared | E.TwoPhaseMut | E.Shallow ->
+  | BShared | BTwoPhaseMut | BShallow ->
       (* **REMARK**: we initially treated shallow borrows like shared borrows.
          In practice this restricted the behaviour too much, so for now we
          forbid them.
       *)
-      assert (bkind <> E.Shallow);
+      assert (bkind <> BShallow);
 
       (* Access the value *)
       let access =
         match bkind with
-        | E.Shared | E.Shallow -> Read
-        | E.TwoPhaseMut -> Write
+        | BShared | BShallow -> Read
+        | BTwoPhaseMut -> Write
         | _ -> raise (Failure "Unreachable")
       in
 
@@ -642,23 +628,21 @@ let eval_rvalue_ref (config : C.config) (p : E.place) (bkind : E.borrow_kind)
         access_rplace_reorganize_and_read config expand_prim_copy access p
       in
       (* Evaluate the borrowing operation *)
-      let eval (cf : V.typed_value -> m_fun) (v : V.typed_value) : m_fun =
+      let eval (cf : typed_value -> m_fun) (v : typed_value) : m_fun =
        fun ctx ->
         (* Generate the fresh borrow id *)
-        let bid = C.fresh_borrow_id () in
+        let bid = fresh_borrow_id () in
         (* Compute the loan value, with which to replace the value at place p *)
         let nv =
-          match v.V.value with
-          | V.Loan (V.SharedLoan (bids, sv)) ->
+          match v.value with
+          | VLoan (VSharedLoan (bids, sv)) ->
               (* Shared loan: insert the new borrow id *)
-              let bids1 = V.BorrowId.Set.add bid bids in
-              { v with V.value = V.Loan (V.SharedLoan (bids1, sv)) }
+              let bids1 = BorrowId.Set.add bid bids in
+              { v with value = VLoan (VSharedLoan (bids1, sv)) }
           | _ ->
               (* Not a shared loan: add a wrapper *)
-              let v' =
-                V.Loan (V.SharedLoan (V.BorrowId.Set.singleton bid, v))
-              in
-              { v with V.value = v' }
+              let v' = VLoan (VSharedLoan (BorrowId.Set.singleton bid, v)) in
+              { v with value = v' }
         in
         (* Update the borrowed value in the context *)
         let ctx = write_place access p nv ctx in
@@ -666,27 +650,27 @@ let eval_rvalue_ref (config : C.config) (p : E.place) (bkind : E.borrow_kind)
          * Note that the reference is *mutable* if we do a two-phase borrow *)
         let ref_kind =
           match bkind with
-          | E.Shared | E.Shallow -> T.Shared
-          | E.TwoPhaseMut -> T.Mut
+          | BShared | BShallow -> RShared
+          | BTwoPhaseMut -> RMut
           | _ -> raise (Failure "Unreachable")
         in
-        let rv_ty = T.Ref (T.Erased, v.ty, ref_kind) in
+        let rv_ty = TRef (RErased, v.ty, ref_kind) in
         let bc =
           match bkind with
-          | E.Shared | E.Shallow ->
+          | BShared | BShallow ->
               (* See the remark at the beginning of the match branch: we
                  handle shallow borrows like shared borrows *)
-              V.SharedBorrow bid
-          | E.TwoPhaseMut -> V.ReservedMutBorrow bid
+              VSharedBorrow bid
+          | BTwoPhaseMut -> VReservedMutBorrow bid
           | _ -> raise (Failure "Unreachable")
         in
-        let rv : V.typed_value = { V.value = V.Borrow bc; ty = rv_ty } in
+        let rv : typed_value = { value = VBorrow bc; ty = rv_ty } in
         (* Continue *)
         cf rv ctx
       in
       (* Compose and apply *)
       comp prepare eval cf ctx
-  | E.Mut ->
+  | BMut ->
       (* Access the value *)
       let access = Write in
       let expand_prim_copy = false in
@@ -694,16 +678,16 @@ let eval_rvalue_ref (config : C.config) (p : E.place) (bkind : E.borrow_kind)
         access_rplace_reorganize_and_read config expand_prim_copy access p
       in
       (* Evaluate the borrowing operation *)
-      let eval (cf : V.typed_value -> m_fun) (v : V.typed_value) : m_fun =
+      let eval (cf : typed_value -> m_fun) (v : typed_value) : m_fun =
        fun ctx ->
         (* Compute the rvalue - wrap the value in a mutable borrow with a fresh id *)
-        let bid = C.fresh_borrow_id () in
-        let rv_ty = T.Ref (T.Erased, v.ty, Mut) in
-        let rv : V.typed_value =
-          { V.value = V.Borrow (V.MutBorrow (bid, v)); ty = rv_ty }
+        let bid = fresh_borrow_id () in
+        let rv_ty = TRef (RErased, v.ty, RMut) in
+        let rv : typed_value =
+          { value = VBorrow (VMutBorrow (bid, v)); ty = rv_ty }
         in
         (* Compute the value with which to replace the value at place p *)
-        let nv = { v with V.value = V.Loan (V.MutLoan bid) } in
+        let nv = { v with value = VLoan (VMutLoan bid) } in
         (* Update the value in the context *)
         let ctx = write_place access p nv ctx in
         (* Continue *)
@@ -712,102 +696,98 @@ let eval_rvalue_ref (config : C.config) (p : E.place) (bkind : E.borrow_kind)
       (* Compose and apply *)
       comp prepare eval cf ctx
 
-let eval_rvalue_aggregate (config : C.config)
-    (aggregate_kind : E.aggregate_kind) (ops : E.operand list)
-    (cf : V.typed_value -> m_fun) : m_fun =
+let eval_rvalue_aggregate (config : config) (aggregate_kind : aggregate_kind)
+    (ops : operand list) (cf : typed_value -> m_fun) : m_fun =
   (* Evaluate the operands *)
   let eval_ops = eval_operands config ops in
   (* Compute the value *)
-  let compute (cf : V.typed_value -> m_fun) (values : V.typed_value list) :
-      m_fun =
+  let compute (cf : typed_value -> m_fun) (values : typed_value list) : m_fun =
    fun ctx ->
     (* Match on the aggregate kind *)
     match aggregate_kind with
-    | E.AggregatedAdt (type_id, opt_variant_id, generics) -> (
+    | AggregatedAdt (type_id, opt_variant_id, generics) -> (
         match type_id with
-        | Tuple ->
-            let tys = List.map (fun (v : V.typed_value) -> v.V.ty) values in
-            let v = V.Adt { variant_id = None; field_values = values } in
-            let generics = TypesUtils.mk_generic_args [] tys [] [] in
-            let ty = T.Adt (T.Tuple, generics) in
-            let aggregated : V.typed_value = { V.value = v; ty } in
+        | TTuple ->
+            let tys = List.map (fun (v : typed_value) -> v.ty) values in
+            let v = VAdt { variant_id = None; field_values = values } in
+            let generics = mk_generic_args [] tys [] [] in
+            let ty = TAdt (TTuple, generics) in
+            let aggregated : typed_value = { value = v; ty } in
             (* Call the continuation *)
             cf aggregated ctx
-        | AdtId def_id ->
+        | TAdtId def_id ->
             (* Sanity checks *)
-            let type_decl = C.ctx_lookup_type_decl ctx def_id in
+            let type_decl = ctx_lookup_type_decl ctx def_id in
             assert (
               List.length type_decl.generics.regions
               = List.length generics.regions);
             let expected_field_types =
-              Assoc.ctx_adt_get_inst_norm_field_etypes ctx def_id opt_variant_id
-                generics
+              AssociatedTypes.ctx_adt_get_inst_norm_field_etypes ctx def_id
+                opt_variant_id generics
             in
             assert (
               expected_field_types
-              = List.map (fun (v : V.typed_value) -> v.V.ty) values);
+              = List.map (fun (v : typed_value) -> v.ty) values);
             (* Construct the value *)
-            let av : V.adt_value =
-              { V.variant_id = opt_variant_id; V.field_values = values }
+            let av : adt_value =
+              { variant_id = opt_variant_id; field_values = values }
             in
-            let aty = T.Adt (T.AdtId def_id, generics) in
-            let aggregated : V.typed_value = { V.value = Adt av; ty = aty } in
+            let aty = TAdt (TAdtId def_id, generics) in
+            let aggregated : typed_value = { value = VAdt av; ty = aty } in
             (* Call the continuation *)
             cf aggregated ctx
-        | Assumed _ -> raise (Failure "Unreachable"))
-    | E.AggregatedArray (ety, cg) -> (
+        | TAssumed _ -> raise (Failure "Unreachable"))
+    | AggregatedArray (ety, cg) -> (
         (* Sanity check: all the values have the proper type *)
-        assert (List.for_all (fun (v : V.typed_value) -> v.V.ty = ety) values);
+        assert (List.for_all (fun (v : typed_value) -> v.ty = ety) values);
         (* Sanity check: the number of values is consistent with the length *)
         let len = (literal_as_scalar (const_generic_as_literal cg)).value in
         assert (len = Z.of_int (List.length values));
         let generics = TypesUtils.mk_generic_args [] [ ety ] [ cg ] [] in
-        let ty = T.Adt (T.Assumed T.Array, generics) in
+        let ty = TAdt (TAssumed TArray, generics) in
         (* In order to generate a better AST, we introduce a symbolic
            value equal to the array. The reason is that otherwise, the
            array we introduce here might be duplicated in the generated
            code: by introducing a symbolic value we introduce a let-binding
            in the generated code. *)
-        let saggregated =
-          mk_fresh_symbolic_typed_value_from_ety V.Aggregate ty
-        in
+        let saggregated = mk_fresh_symbolic_typed_value Aggregate ty in
         (* Call the continuation *)
         match cf saggregated ctx with
         | None -> None
         | Some e ->
             (* Introduce the symbolic value in the AST *)
             let sv = ValuesUtils.value_as_symbolic saggregated.value in
-            Some (SymbolicAst.IntroSymbolic (ctx, None, sv, Array values, e)))
+            Some (SymbolicAst.IntroSymbolic (ctx, None, sv, VaArray values, e)))
   in
   (* Compose and apply *)
   comp eval_ops compute cf
 
-let eval_rvalue_not_global (config : C.config) (rvalue : E.rvalue)
-    (cf : (V.typed_value, eval_error) result -> m_fun) : m_fun =
+let eval_rvalue_not_global (config : config) (rvalue : rvalue)
+    (cf : (typed_value, eval_error) result -> m_fun) : m_fun =
  fun ctx ->
   log#ldebug (lazy "eval_rvalue");
   (* Small helpers *)
-  let wrap_in_result (cf : (V.typed_value, eval_error) result -> m_fun)
-      (v : V.typed_value) : m_fun =
+  let wrap_in_result (cf : (typed_value, eval_error) result -> m_fun)
+      (v : typed_value) : m_fun =
     cf (Ok v)
   in
   let comp_wrap f = comp f wrap_in_result cf in
   (* Delegate to the proper auxiliary function *)
   match rvalue with
-  | E.Use op -> comp_wrap (eval_operand config op) ctx
-  | E.RvRef (p, bkind) -> comp_wrap (eval_rvalue_ref config p bkind) ctx
-  | E.UnaryOp (unop, op) -> eval_unary_op config unop op cf ctx
-  | E.BinaryOp (binop, op1, op2) -> eval_binary_op config binop op1 op2 cf ctx
-  | E.Aggregate (aggregate_kind, ops) ->
+  | Use op -> comp_wrap (eval_operand config op) ctx
+  | RvRef (p, bkind) -> comp_wrap (eval_rvalue_ref config p bkind) ctx
+  | UnaryOp (unop, op) -> eval_unary_op config unop op cf ctx
+  | BinaryOp (binop, op1, op2) -> eval_binary_op config binop op1 op2 cf ctx
+  | Aggregate (aggregate_kind, ops) ->
       comp_wrap (eval_rvalue_aggregate config aggregate_kind ops) ctx
-  | E.Discriminant _ ->
+  | Discriminant _ ->
       raise
         (Failure
            "Unreachable: discriminant reads should have been eliminated from \
             the AST")
-  | E.Global _ -> raise (Failure "Unreachable")
+  | Global _ -> raise (Failure "Unreachable")
 
-let eval_fake_read (config : C.config) (p : E.place) : cm_fun =
+let eval_fake_read (config : config) (p : place) : cm_fun =
  fun cf ctx ->
   let expand_prim_copy = false in
   let cf_prepare cf =
diff --git a/compiler/InterpreterExpressions.mli b/compiler/InterpreterExpressions.mli
index 3beba610..f8d979f4 100644
--- a/compiler/InterpreterExpressions.mli
+++ b/compiler/InterpreterExpressions.mli
@@ -1,13 +1,6 @@
-module T = Types
-module PV = PrimitiveValues
-module V = Values
-module LA = LlbcAst
-module E = Expressions
-module C = Contexts
-module Subst = Substitute
-module L = Logging
-module Inv = Invariants
-module S = SynthesizeSymbolic
+open Expressions
+open Values
+open Contexts
 open Cps
 open InterpreterPaths
 
@@ -19,7 +12,7 @@ open InterpreterPaths
     This function doesn't reorganize the context to make sure we can read
     the place. If needs be, you should call {!InterpreterPaths.update_ctx_along_read_place} first.
  *)
-val read_place : access_kind -> E.place -> (V.typed_value -> m_fun) -> m_fun
+val read_place : access_kind -> place -> (typed_value -> m_fun) -> m_fun
 
 (** Auxiliary function.
 
@@ -38,12 +31,7 @@ val read_place : access_kind -> E.place -> (V.typed_value -> m_fun) -> m_fun
     primitively copyable and contain borrows.
  *)
 val access_rplace_reorganize_and_read :
-  C.config ->
-  bool ->
-  access_kind ->
-  E.place ->
-  (V.typed_value -> m_fun) ->
-  m_fun
+  config -> bool -> access_kind -> place -> (typed_value -> m_fun) -> m_fun
 
 (** Evaluate an operand.
 
@@ -54,11 +42,11 @@ val access_rplace_reorganize_and_read :
     of the environment, before evaluating all the operands at once.
     Use {!eval_operands} instead.
  *)
-val eval_operand : C.config -> E.operand -> (V.typed_value -> m_fun) -> m_fun
+val eval_operand : config -> operand -> (typed_value -> m_fun) -> m_fun
 
 (** Evaluate several operands at once. *)
 val eval_operands :
-  C.config -> E.operand list -> (V.typed_value list -> m_fun) -> m_fun
+  config -> operand list -> (typed_value list -> m_fun) -> m_fun
 
 (** Evaluate an rvalue which is not a global (globals are handled elsewhere).
 
@@ -68,7 +56,7 @@ val eval_operands :
     reads should have been eliminated from the AST.
  *)
 val eval_rvalue_not_global :
-  C.config -> E.rvalue -> ((V.typed_value, eval_error) result -> m_fun) -> m_fun
+  config -> rvalue -> ((typed_value, eval_error) result -> m_fun) -> m_fun
 
 (** Evaluate a fake read (update the context so that we can read a place) *)
-val eval_fake_read : C.config -> E.place -> cm_fun
+val eval_fake_read : config -> place -> cm_fun
diff --git a/compiler/InterpreterLoops.ml b/compiler/InterpreterLoops.ml
index 5b170ac5..ed2a9587 100644
--- a/compiler/InterpreterLoops.ml
+++ b/compiler/InterpreterLoops.ml
@@ -1,13 +1,8 @@
-module T = Types
-module PV = PrimitiveValues
-module V = Values
-module E = Expressions
-module C = Contexts
-module Subst = Substitute
-module A = LlbcAst
-module L = Logging
+open Types
+open Values
+open Contexts
 open ValuesUtils
-module Inv = Invariants
+open Meta
 module S = SynthesizeSymbolic
 open Cps
 open InterpreterUtils
@@ -16,14 +11,14 @@ open InterpreterLoopsMatchCtxs
 open InterpreterLoopsFixedPoint
 
 (** The local logger *)
-let log = L.loops_log
+let log = Logging.loops_log
 
 (** Evaluate a loop in concrete mode *)
 let eval_loop_concrete (eval_loop_body : st_cm_fun) : st_cm_fun =
  fun cf ctx ->
   (* We need a loop id for the [LoopReturn]. In practice it won't be used
      (it is useful only for the symbolic execution *)
-  let loop_id = C.fresh_loop_id () in
+  let loop_id = fresh_loop_id () in
   (* Continuation for after we evaluate the loop body: depending the result
      of doing one loop iteration:
      - redoes a loop iteration
@@ -66,15 +61,15 @@ let eval_loop_concrete (eval_loop_body : st_cm_fun) : st_cm_fun =
   eval_loop_body reeval_loop_body ctx
 
 (** Evaluate a loop in symbolic mode *)
-let eval_loop_symbolic (config : C.config) (eval_loop_body : st_cm_fun) :
-    st_cm_fun =
+let eval_loop_symbolic (config : config) (meta : meta)
+    (eval_loop_body : st_cm_fun) : st_cm_fun =
  fun cf ctx ->
   (* Debug *)
   log#ldebug
     (lazy ("eval_loop_symbolic:\nContext:\n" ^ eval_ctx_to_string ctx ^ "\n\n"));
 
   (* Generate a fresh loop id *)
-  let loop_id = C.fresh_loop_id () in
+  let loop_id = fresh_loop_id () in
 
   (* Compute the fixed point at the loop entrance *)
   let fp_ctx, fixed_ids, rg_to_abs =
@@ -89,7 +84,7 @@ let eval_loop_symbolic (config : C.config) (eval_loop_body : st_cm_fun) :
 
   (* Compute the loop input parameters *)
   let fresh_sids, input_svalues = compute_fp_ctx_symbolic_values ctx fp_ctx in
-  let fp_input_svalues = List.map (fun sv -> sv.V.sv_id) input_svalues in
+  let fp_input_svalues = List.map (fun sv -> sv.sv_id) input_svalues in
 
   (* Synthesize the end of the function - we simply match the context at the
      loop entry with the fixed point: in the synthesized code, the function
@@ -140,9 +135,9 @@ let eval_loop_symbolic (config : C.config) (eval_loop_body : st_cm_fun) :
       ^ "\n- fixed point:\n"
       ^ eval_ctx_to_string_no_filter fp_ctx
       ^ "\n- fixed_sids: "
-      ^ V.SymbolicValueId.Set.show fixed_ids.sids
+      ^ SymbolicValueId.Set.show fixed_ids.sids
       ^ "\n- fresh_sids: "
-      ^ V.SymbolicValueId.Set.show fresh_sids
+      ^ SymbolicValueId.Set.show fresh_sids
       ^ "\n- input_svalues: "
       ^ Print.list_to_string (symbolic_value_to_string ctx) input_svalues
       ^ "\n\n"));
@@ -155,9 +150,9 @@ let eval_loop_symbolic (config : C.config) (eval_loop_body : st_cm_fun) :
      is important in {!SymbolicToPure}, where we expect the given back
      values to have a specific order.
   *)
-  let compute_abs_given_back_tys (abs : V.abs) : T.RegionId.Set.t * T.rty list =
-    let is_borrow (av : V.typed_avalue) : bool =
-      match av.V.value with
+  let compute_abs_given_back_tys (abs : abs) : RegionId.Set.t * rty list =
+    let is_borrow (av : typed_avalue) : bool =
+      match av.value with
       | ABorrow _ -> true
       | ALoan _ -> false
       | _ -> raise (Failure "Unreachable")
@@ -166,25 +161,25 @@ let eval_loop_symbolic (config : C.config) (eval_loop_body : st_cm_fun) :
 
     let borrows =
       List.filter_map
-        (fun av ->
-          match av.V.value with
-          | V.ABorrow (V.AMutBorrow (bid, child_av)) ->
-              assert (is_aignored child_av.V.value);
-              Some (bid, child_av.V.ty)
-          | V.ABorrow (V.ASharedBorrow _) -> None
+        (fun (av : typed_avalue) ->
+          match av.value with
+          | ABorrow (AMutBorrow (bid, child_av)) ->
+              assert (is_aignored child_av.value);
+              Some (bid, child_av.ty)
+          | ABorrow (ASharedBorrow _) -> None
           | _ -> raise (Failure "Unreachable"))
         borrows
     in
-    let borrows = ref (V.BorrowId.Map.of_list borrows) in
+    let borrows = ref (BorrowId.Map.of_list borrows) in
 
     let loan_ids =
       List.filter_map
-        (fun av ->
-          match av.V.value with
-          | V.ALoan (V.AMutLoan (bid, child_av)) ->
-              assert (is_aignored child_av.V.value);
+        (fun (av : typed_avalue) ->
+          match av.value with
+          | ALoan (AMutLoan (bid, child_av)) ->
+              assert (is_aignored child_av.value);
               Some bid
-          | V.ALoan (V.ASharedLoan _) -> None
+          | ALoan (ASharedLoan _) -> None
           | _ -> raise (Failure "Unreachable"))
         loans
     in
@@ -194,28 +189,29 @@ let eval_loop_symbolic (config : C.config) (eval_loop_body : st_cm_fun) :
       List.map
         (fun lid ->
           let bid =
-            V.BorrowId.InjSubst.find lid fp_bl_corresp.loan_to_borrow_id_map
+            BorrowId.InjSubst.find lid fp_bl_corresp.loan_to_borrow_id_map
           in
-          let ty = V.BorrowId.Map.find bid !borrows in
-          borrows := V.BorrowId.Map.remove bid !borrows;
+          let ty = BorrowId.Map.find bid !borrows in
+          borrows := BorrowId.Map.remove bid !borrows;
           ty)
         loan_ids
     in
-    assert (V.BorrowId.Map.is_empty !borrows);
+    assert (BorrowId.Map.is_empty !borrows);
 
     (abs.regions, given_back_tys)
   in
   let rg_to_given_back =
-    T.RegionGroupId.Map.map compute_abs_given_back_tys rg_to_abs
+    RegionGroupId.Map.map compute_abs_given_back_tys rg_to_abs
   in
 
   (* Put together *)
   S.synthesize_loop loop_id input_svalues fresh_sids rg_to_given_back end_expr
-    loop_expr
+    loop_expr meta
 
-let eval_loop (config : C.config) (eval_loop_body : st_cm_fun) : st_cm_fun =
+let eval_loop (config : config) (meta : meta) (eval_loop_body : st_cm_fun) :
+    st_cm_fun =
  fun cf ctx ->
-  match config.C.mode with
+  match config.mode with
   | ConcreteMode -> eval_loop_concrete eval_loop_body cf ctx
   | SymbolicMode ->
       (* We want to make sure the loop will *not* manipulate shared avalues
@@ -237,4 +233,4 @@ let eval_loop (config : C.config) (eval_loop_body : st_cm_fun) : st_cm_fun =
          *non-fixed* abstractions.
       *)
       let cc = prepare_ashared_loans None in
-      comp cc (eval_loop_symbolic config eval_loop_body) cf ctx
+      comp cc (eval_loop_symbolic config meta eval_loop_body) cf ctx
diff --git a/compiler/InterpreterLoops.mli b/compiler/InterpreterLoops.mli
index 7395739b..03633861 100644
--- a/compiler/InterpreterLoops.mli
+++ b/compiler/InterpreterLoops.mli
@@ -56,7 +56,9 @@
     From here, we deduce that [abs@fp { MB l0, ML l1}] is the loop abstraction.
   *)
 
-module C = Contexts
+open Contexts
+open Cps
+open Meta
 
 (** Evaluate a loop *)
-val eval_loop : C.config -> Cps.st_cm_fun -> Cps.st_cm_fun
+val eval_loop : config -> meta -> st_cm_fun -> st_cm_fun
diff --git a/compiler/InterpreterLoopsCore.ml b/compiler/InterpreterLoopsCore.ml
index 6e33c75b..d14230c6 100644
--- a/compiler/InterpreterLoopsCore.ml
+++ b/compiler/InterpreterLoopsCore.ml
@@ -1,26 +1,17 @@
 (** Core definitions for the [IntepreterLoops*] *)
 
-module T = Types
-module PV = PrimitiveValues
-module V = Values
-module E = Expressions
-module C = Contexts
-module Subst = Substitute
-module A = LlbcAst
-module L = Logging
-module Inv = Invariants
-module S = SynthesizeSymbolic
-module UF = UnionFind
+open Types
+open Values
+open Contexts
 open InterpreterUtils
-open InterpreterExpressions
 
 type updt_env_kind =
-  | AbsInLeft of V.AbstractionId.id
-  | LoanInLeft of V.BorrowId.id
-  | LoansInLeft of V.BorrowId.Set.t
-  | AbsInRight of V.AbstractionId.id
-  | LoanInRight of V.BorrowId.id
-  | LoansInRight of V.BorrowId.Set.t
+  | AbsInLeft of AbstractionId.id
+  | LoanInLeft of BorrowId.id
+  | LoansInLeft of BorrowId.Set.t
+  | AbsInRight of AbstractionId.id
+  | LoanInRight of BorrowId.id
+  | LoansInRight of BorrowId.Set.t
 
 (** Utility exception *)
 exception ValueMatchFailure of updt_env_kind
@@ -28,10 +19,10 @@ exception ValueMatchFailure of updt_env_kind
 (** Utility exception *)
 exception Distinct of string
 
-type ctx_or_update = (C.eval_ctx, updt_env_kind) result
+type ctx_or_update = (eval_ctx, updt_env_kind) result
 
 (** Union Find *)
-module UnionFind = UF.Make (UF.StoreMap)
+module UF = UnionFind.Make (UnionFind.StoreMap)
 
 (** A small utility -
 
@@ -41,13 +32,13 @@ module UnionFind = UF.Make (UF.StoreMap)
     instance, [borrow_to_abs] maps to a *set* of ids).
 *)
 type abs_borrows_loans_maps = {
-  abs_ids : V.AbstractionId.id list;
-  abs_to_borrows : V.BorrowId.Set.t V.AbstractionId.Map.t;
-  abs_to_loans : V.BorrowId.Set.t V.AbstractionId.Map.t;
-  abs_to_borrows_loans : V.BorrowId.Set.t V.AbstractionId.Map.t;
-  borrow_to_abs : V.AbstractionId.Set.t V.BorrowId.Map.t;
-  loan_to_abs : V.AbstractionId.Set.t V.BorrowId.Map.t;
-  borrow_loan_to_abs : V.AbstractionId.Set.t V.BorrowId.Map.t;
+  abs_ids : AbstractionId.id list;
+  abs_to_borrows : BorrowId.Set.t AbstractionId.Map.t;
+  abs_to_loans : BorrowId.Set.t AbstractionId.Map.t;
+  abs_to_borrows_loans : BorrowId.Set.t AbstractionId.Map.t;
+  borrow_to_abs : AbstractionId.Set.t BorrowId.Map.t;
+  loan_to_abs : AbstractionId.Set.t BorrowId.Map.t;
+  borrow_loan_to_abs : AbstractionId.Set.t BorrowId.Map.t;
 }
 
 (** See {!InterpreterLoopsMatchCtxs.MakeMatcher} and {!InterpreterLoopsCore.Matcher}.
@@ -56,14 +47,14 @@ type abs_borrows_loans_maps = {
     {!InterpreterLoopsMatchCtxs.MakeMatcher} functor.
   *)
 module type PrimMatcher = sig
-  val match_etys : T.ety -> T.ety -> T.ety
-  val match_rtys : T.rty -> T.rty -> T.rty
+  val match_etys : ety -> ety -> ety
+  val match_rtys : rty -> rty -> rty
 
   (** The input primitive values are not equal *)
-  val match_distinct_literals : T.ety -> V.literal -> V.literal -> V.typed_value
+  val match_distinct_literals : ety -> literal -> literal -> typed_value
 
   (** The input ADTs don't have the same variant *)
-  val match_distinct_adts : T.ety -> V.adt_value -> V.adt_value -> V.typed_value
+  val match_distinct_adts : ety -> adt_value -> adt_value -> typed_value
 
   (** The meta-value is the result of a match.
 
@@ -76,11 +67,11 @@ module type PrimMatcher = sig
       calling the match function.
    *)
   val match_shared_borrows :
-    (V.typed_value -> V.typed_value -> V.typed_value) ->
-    T.ety ->
-    V.borrow_id ->
-    V.borrow_id ->
-    V.borrow_id
+    (typed_value -> typed_value -> typed_value) ->
+    ety ->
+    borrow_id ->
+    borrow_id ->
+    borrow_id
 
   (** The input parameters are:
       - [ty]
@@ -91,13 +82,13 @@ module type PrimMatcher = sig
       - [bv]: the result of matching [bv0] with [bv1]
   *)
   val match_mut_borrows :
-    T.ety ->
-    V.borrow_id ->
-    V.typed_value ->
-    V.borrow_id ->
-    V.typed_value ->
-    V.typed_value ->
-    V.borrow_id * V.typed_value
+    ety ->
+    borrow_id ->
+    typed_value ->
+    borrow_id ->
+    typed_value ->
+    typed_value ->
+    borrow_id * typed_value
 
   (** Parameters:
       [ty]
@@ -106,17 +97,16 @@ module type PrimMatcher = sig
       [v]: the result of matching the shared values coming from the two loans
    *)
   val match_shared_loans :
-    T.ety ->
-    V.loan_id_set ->
-    V.loan_id_set ->
-    V.typed_value ->
-    V.loan_id_set * V.typed_value
+    ety ->
+    loan_id_set ->
+    loan_id_set ->
+    typed_value ->
+    loan_id_set * typed_value
 
-  val match_mut_loans : T.ety -> V.loan_id -> V.loan_id -> V.loan_id
+  val match_mut_loans : ety -> loan_id -> loan_id -> loan_id
 
   (** There are no constraints on the input symbolic values *)
-  val match_symbolic_values :
-    V.symbolic_value -> V.symbolic_value -> V.symbolic_value
+  val match_symbolic_values : symbolic_value -> symbolic_value -> symbolic_value
 
   (** Match a symbolic value with a value which is not symbolic.
 
@@ -126,7 +116,7 @@ module type PrimMatcher = sig
       end loans in one of the two environments).
    *)
   val match_symbolic_with_other :
-    bool -> V.symbolic_value -> V.typed_value -> V.typed_value
+    bool -> symbolic_value -> typed_value -> typed_value
 
   (** Match a bottom value with a value which is not bottom.
 
@@ -135,11 +125,11 @@ module type PrimMatcher = sig
       is important when throwing exceptions, for instance when we need to
       end loans in one of the two environments).
    *)
-  val match_bottom_with_other : bool -> V.typed_value -> V.typed_value
+  val match_bottom_with_other : bool -> typed_value -> typed_value
 
   (** The input ADTs don't have the same variant *)
   val match_distinct_aadts :
-    T.rty -> V.adt_avalue -> T.rty -> V.adt_avalue -> T.rty -> V.typed_avalue
+    rty -> adt_avalue -> rty -> adt_avalue -> rty -> typed_avalue
 
   (** Parameters:
       [ty0]
@@ -149,7 +139,7 @@ module type PrimMatcher = sig
       [ty]: result of matching ty0 and ty1
    *)
   val match_ashared_borrows :
-    T.rty -> V.borrow_id -> T.rty -> V.borrow_id -> T.rty -> V.typed_avalue
+    rty -> borrow_id -> rty -> borrow_id -> rty -> typed_avalue
 
   (** Parameters:
       [ty0]
@@ -162,15 +152,15 @@ module type PrimMatcher = sig
       [av]: result of matching av0 and av1
    *)
   val match_amut_borrows :
-    T.rty ->
-    V.borrow_id ->
-    V.typed_avalue ->
-    T.rty ->
-    V.borrow_id ->
-    V.typed_avalue ->
-    T.rty ->
-    V.typed_avalue ->
-    V.typed_avalue
+    rty ->
+    borrow_id ->
+    typed_avalue ->
+    rty ->
+    borrow_id ->
+    typed_avalue ->
+    rty ->
+    typed_avalue ->
+    typed_avalue
 
   (** Parameters:
       [ty0]
@@ -186,18 +176,18 @@ module type PrimMatcher = sig
       [av]: result of matching av0 and av1
    *)
   val match_ashared_loans :
-    T.rty ->
-    V.loan_id_set ->
-    V.typed_value ->
-    V.typed_avalue ->
-    T.rty ->
-    V.loan_id_set ->
-    V.typed_value ->
-    V.typed_avalue ->
-    T.rty ->
-    V.typed_value ->
-    V.typed_avalue ->
-    V.typed_avalue
+    rty ->
+    loan_id_set ->
+    typed_value ->
+    typed_avalue ->
+    rty ->
+    loan_id_set ->
+    typed_value ->
+    typed_avalue ->
+    rty ->
+    typed_value ->
+    typed_avalue ->
+    typed_avalue
 
   (** Parameters:
       [ty0]
@@ -210,20 +200,20 @@ module type PrimMatcher = sig
       [av]: result of matching av0 and av1
    *)
   val match_amut_loans :
-    T.rty ->
-    V.borrow_id ->
-    V.typed_avalue ->
-    T.rty ->
-    V.borrow_id ->
-    V.typed_avalue ->
-    T.rty ->
-    V.typed_avalue ->
-    V.typed_avalue
+    rty ->
+    borrow_id ->
+    typed_avalue ->
+    rty ->
+    borrow_id ->
+    typed_avalue ->
+    rty ->
+    typed_avalue ->
+    typed_avalue
 
   (** Match two arbitrary avalues whose constructors don't match (this function
       is typically used to raise the proper exception).
    *)
-  val match_avalues : V.typed_avalue -> V.typed_avalue -> V.typed_avalue
+  val match_avalues : typed_avalue -> typed_avalue -> typed_avalue
 end
 
 module type Matcher = sig
@@ -231,15 +221,14 @@ module type Matcher = sig
 
       Rem.: this function raises exceptions of type {!Aeneas.InterpreterLoopsCore.ValueMatchFailure}.
    *)
-  val match_typed_values :
-    C.eval_ctx -> V.typed_value -> V.typed_value -> V.typed_value
+  val match_typed_values : eval_ctx -> typed_value -> typed_value -> typed_value
 
   (** Match two avalues.
 
       Rem.: this function raises exceptions of type {!Aeneas.InterpreterLoopsCore.ValueMatchFailure}.
    *)
   val match_typed_avalues :
-    C.eval_ctx -> V.typed_avalue -> V.typed_avalue -> V.typed_avalue
+    eval_ctx -> typed_avalue -> typed_avalue -> typed_avalue
 end
 
 (** See {!InterpreterLoopsMatchCtxs.MakeCheckEquivMatcher} and
@@ -252,78 +241,75 @@ module type MatchCheckEquivState = sig
       a source context with a target context. *)
   val check_equiv : bool
 
-  val ctx : C.eval_ctx
-  val rid_map : T.RegionId.InjSubst.t ref
+  val ctx : eval_ctx
+  val rid_map : RegionId.InjSubst.t ref
 
   (** Substitution for the loan and borrow ids - used only if [check_equiv] is true *)
-  val blid_map : V.BorrowId.InjSubst.t ref
+  val blid_map : BorrowId.InjSubst.t ref
 
   (** Substitution for the borrow ids - used only if [check_equiv] is false *)
-  val borrow_id_map : V.BorrowId.InjSubst.t ref
+  val borrow_id_map : BorrowId.InjSubst.t ref
 
   (** Substitution for the loans ids - used only if [check_equiv] is false *)
-  val loan_id_map : V.BorrowId.InjSubst.t ref
+  val loan_id_map : BorrowId.InjSubst.t ref
 
-  val sid_map : V.SymbolicValueId.InjSubst.t ref
-  val sid_to_value_map : V.typed_value V.SymbolicValueId.Map.t ref
-  val aid_map : V.AbstractionId.InjSubst.t ref
-  val lookup_shared_value_in_ctx0 : V.BorrowId.id -> V.typed_value
-  val lookup_shared_value_in_ctx1 : V.BorrowId.id -> V.typed_value
+  val sid_map : SymbolicValueId.InjSubst.t ref
+  val sid_to_value_map : typed_value SymbolicValueId.Map.t ref
+  val aid_map : AbstractionId.InjSubst.t ref
+  val lookup_shared_value_in_ctx0 : BorrowId.id -> typed_value
+  val lookup_shared_value_in_ctx1 : BorrowId.id -> typed_value
 end
 
 module type CheckEquivMatcher = sig
   include PrimMatcher
 
-  val match_aid : V.abstraction_id -> V.abstraction_id -> V.abstraction_id
+  val match_aid : abstraction_id -> abstraction_id -> abstraction_id
 
   val match_aidl :
-    V.abstraction_id list -> V.abstraction_id list -> V.abstraction_id list
+    abstraction_id list -> abstraction_id list -> abstraction_id list
 
   val match_aids :
-    V.abstraction_id_set -> V.abstraction_id_set -> V.abstraction_id_set
-
-  val match_rid : V.region_id -> V.region_id -> V.region_id
-  val match_rids : V.region_id_set -> V.region_id_set -> V.region_id_set
-  val match_borrow_id : V.borrow_id -> V.borrow_id -> V.borrow_id
-
-  val match_borrow_idl :
-    V.borrow_id list -> V.borrow_id list -> V.borrow_id list
-
-  val match_borrow_ids : V.borrow_id_set -> V.borrow_id_set -> V.borrow_id_set
-  val match_loan_id : V.loan_id -> V.loan_id -> V.loan_id
-  val match_loan_idl : V.loan_id list -> V.loan_id list -> V.loan_id list
-  val match_loan_ids : V.loan_id_set -> V.loan_id_set -> V.loan_id_set
+    abstraction_id_set -> abstraction_id_set -> abstraction_id_set
+
+  val match_rid : region_id -> region_id -> region_id
+  val match_rids : region_id_set -> region_id_set -> region_id_set
+  val match_borrow_id : borrow_id -> borrow_id -> borrow_id
+  val match_borrow_idl : borrow_id list -> borrow_id list -> borrow_id list
+  val match_borrow_ids : borrow_id_set -> borrow_id_set -> borrow_id_set
+  val match_loan_id : loan_id -> loan_id -> loan_id
+  val match_loan_idl : loan_id list -> loan_id list -> loan_id list
+  val match_loan_ids : loan_id_set -> loan_id_set -> loan_id_set
 end
 
 (** See {!InterpreterLoopsMatchCtxs.match_ctxs} *)
 type ids_maps = {
-  aid_map : V.AbstractionId.InjSubst.t;
-  blid_map : V.BorrowId.InjSubst.t;
+  aid_map : AbstractionId.InjSubst.t;
+  blid_map : BorrowId.InjSubst.t;
       (** Substitution for the loan and borrow ids *)
-  borrow_id_map : V.BorrowId.InjSubst.t;  (** Substitution for the borrow ids *)
-  loan_id_map : V.BorrowId.InjSubst.t;  (** Substitution for the loan ids *)
-  rid_map : T.RegionId.InjSubst.t;
-  sid_map : V.SymbolicValueId.InjSubst.t;
-  sid_to_value_map : V.typed_value V.SymbolicValueId.Map.t;
+  borrow_id_map : BorrowId.InjSubst.t;  (** Substitution for the borrow ids *)
+  loan_id_map : BorrowId.InjSubst.t;  (** Substitution for the loan ids *)
+  rid_map : RegionId.InjSubst.t;
+  sid_map : SymbolicValueId.InjSubst.t;
+  sid_to_value_map : typed_value SymbolicValueId.Map.t;
 }
 [@@deriving show]
 
 type borrow_loan_corresp = {
-  borrow_to_loan_id_map : V.BorrowId.InjSubst.t;
-  loan_to_borrow_id_map : V.BorrowId.InjSubst.t;
+  borrow_to_loan_id_map : BorrowId.InjSubst.t;
+  loan_to_borrow_id_map : BorrowId.InjSubst.t;
 }
 [@@deriving show]
 
 (* Very annoying: functors only take modules as inputs... *)
 module type MatchJoinState = sig
   (** The current context *)
-  val ctx : C.eval_ctx
+  val ctx : eval_ctx
 
   (** The current loop *)
-  val loop_id : V.LoopId.id
+  val loop_id : LoopId.id
 
   (** The abstractions introduced when performing the matches *)
-  val nabs : V.abs list ref
+  val nabs : abs list ref
 end
 
 (** Split an environment between the fixed abstractions, values, etc. and
@@ -331,36 +317,36 @@ end
 
     Returns: (fixed, new abs, new dummies)
  *)
-let ctx_split_fixed_new (fixed_ids : ids_sets) (ctx : C.eval_ctx) :
-    C.env * V.abs list * V.typed_value list =
-  let is_fresh_did (id : C.DummyVarId.id) : bool =
-    not (C.DummyVarId.Set.mem id fixed_ids.dids)
+let ctx_split_fixed_new (fixed_ids : ids_sets) (ctx : eval_ctx) :
+    env * abs list * typed_value list =
+  let is_fresh_did (id : DummyVarId.id) : bool =
+    not (DummyVarId.Set.mem id fixed_ids.dids)
   in
-  let is_fresh_abs_id (id : V.AbstractionId.id) : bool =
-    not (V.AbstractionId.Set.mem id fixed_ids.aids)
+  let is_fresh_abs_id (id : AbstractionId.id) : bool =
+    not (AbstractionId.Set.mem id fixed_ids.aids)
   in
   (* Filter the new abstractions and dummy variables (there shouldn't be any new dummy variable
      though) in the target context *)
-  let is_fresh (ee : C.env_elem) : bool =
+  let is_fresh (ee : env_elem) : bool =
     match ee with
-    | C.Var (VarBinder _, _) | C.Frame -> false
-    | C.Var (DummyBinder bv, _) -> is_fresh_did bv
-    | C.Abs abs -> is_fresh_abs_id abs.abs_id
+    | EBinding (BVar _, _) | EFrame -> false
+    | EBinding (BDummy bv, _) -> is_fresh_did bv
+    | EAbs abs -> is_fresh_abs_id abs.abs_id
   in
   let new_eel, filt_env = List.partition is_fresh ctx.env in
-  let is_abs ee = match ee with C.Abs _ -> true | _ -> false in
+  let is_abs ee = match ee with EAbs _ -> true | _ -> false in
   let new_absl, new_dummyl = List.partition is_abs new_eel in
   let new_absl =
     List.map
       (fun ee ->
-        match ee with C.Abs abs -> abs | _ -> raise (Failure "Unreachable"))
+        match ee with EAbs abs -> abs | _ -> raise (Failure "Unreachable"))
       new_absl
   in
   let new_dummyl =
     List.map
       (fun ee ->
         match ee with
-        | C.Var (DummyBinder _, v) -> v
+        | EBinding (BDummy _, v) -> v
         | _ -> raise (Failure "Unreachable"))
       new_dummyl
   in
@@ -370,7 +356,7 @@ let ids_sets_empty_borrows_loans (ids : ids_sets) : ids_sets =
   let { aids; blids = _; borrow_ids = _; loan_ids = _; dids; rids; sids } =
     ids
   in
-  let empty = V.BorrowId.Set.empty in
+  let empty = BorrowId.Set.empty in
   let ids =
     {
       aids;
diff --git a/compiler/InterpreterLoopsFixedPoint.ml b/compiler/InterpreterLoopsFixedPoint.ml
index 4310f017..3cc0a5f0 100644
--- a/compiler/InterpreterLoopsFixedPoint.ml
+++ b/compiler/InterpreterLoopsFixedPoint.ml
@@ -1,14 +1,8 @@
-module T = Types
-module PV = PrimitiveValues
-module V = Values
-module E = Expressions
-module C = Contexts
-module Subst = Substitute
-module A = LlbcAst
-module L = Logging
+open Types
+open Values
+open Contexts
 open TypesUtils
 open ValuesUtils
-module Inv = Invariants
 module S = SynthesizeSymbolic
 open Cps
 open InterpreterUtils
@@ -17,7 +11,7 @@ open InterpreterLoopsMatchCtxs
 open InterpreterLoopsJoinCtxs
 
 (** The local logger *)
-let log = L.loops_fixed_point_log
+let log = Logging.loops_fixed_point_log
 
 (** Reorder the loans and borrows in the fresh abstractions.
 
@@ -26,17 +20,17 @@ let log = L.loops_fixed_point_log
     called typically after we merge abstractions together (see {!collapse_ctx}
     for instance).
  *)
-let reorder_loans_borrows_in_fresh_abs (old_abs_ids : V.AbstractionId.Set.t)
-    (ctx : C.eval_ctx) : C.eval_ctx =
-  let reorder_in_fresh_abs (abs : V.abs) : V.abs =
+let reorder_loans_borrows_in_fresh_abs (old_abs_ids : AbstractionId.Set.t)
+    (ctx : eval_ctx) : eval_ctx =
+  let reorder_in_fresh_abs (abs : abs) : abs =
     (* Split between the loans and borrows *)
-    let is_borrow (av : V.typed_avalue) : bool =
-      match av.V.value with
+    let is_borrow (av : typed_avalue) : bool =
+      match av.value with
       | ABorrow _ -> true
       | ALoan _ -> false
       | _ -> raise (Failure "Unexpected")
     in
-    let aborrows, aloans = List.partition is_borrow abs.V.avalues in
+    let aborrows, aloans = List.partition is_borrow abs.avalues in
 
     (* Reoder the borrows, and the loans.
 
@@ -44,40 +38,40 @@ let reorder_loans_borrows_in_fresh_abs (old_abs_ids : V.AbstractionId.Set.t)
        and the borrows to find fixed points is simply to sort them by increasing
        order of id (taking the smallest id of a set of ids, in case of sets).
     *)
-    let get_borrow_id (av : V.typed_avalue) : V.BorrowId.id =
-      match av.V.value with
-      | V.ABorrow (V.AMutBorrow (bid, _) | V.ASharedBorrow bid) -> bid
+    let get_borrow_id (av : typed_avalue) : BorrowId.id =
+      match av.value with
+      | ABorrow (AMutBorrow (bid, _) | ASharedBorrow bid) -> bid
       | _ -> raise (Failure "Unexpected")
     in
-    let get_loan_id (av : V.typed_avalue) : V.BorrowId.id =
-      match av.V.value with
-      | V.ALoan (V.AMutLoan (lid, _)) -> lid
-      | V.ALoan (V.ASharedLoan (lids, _, _)) -> V.BorrowId.Set.min_elt lids
+    let get_loan_id (av : typed_avalue) : BorrowId.id =
+      match av.value with
+      | ALoan (AMutLoan (lid, _)) -> lid
+      | ALoan (ASharedLoan (lids, _, _)) -> BorrowId.Set.min_elt lids
       | _ -> raise (Failure "Unexpected")
     in
     (* We use ordered maps to reorder the borrows and loans *)
-    let reorder (get_bid : V.typed_avalue -> V.BorrowId.id)
-        (values : V.typed_avalue list) : V.typed_avalue list =
+    let reorder (get_bid : typed_avalue -> BorrowId.id)
+        (values : typed_avalue list) : typed_avalue list =
       List.map snd
-        (V.BorrowId.Map.bindings
-           (V.BorrowId.Map.of_list (List.map (fun v -> (get_bid v, v)) values)))
+        (BorrowId.Map.bindings
+           (BorrowId.Map.of_list (List.map (fun v -> (get_bid v, v)) values)))
     in
     let aborrows = reorder get_borrow_id aborrows in
     let aloans = reorder get_loan_id aloans in
     let avalues = List.append aborrows aloans in
-    { abs with V.avalues }
+    { abs with avalues }
   in
 
-  let reorder_in_abs (abs : V.abs) =
-    if V.AbstractionId.Set.mem abs.abs_id old_abs_ids then abs
+  let reorder_in_abs (abs : abs) =
+    if AbstractionId.Set.mem abs.abs_id old_abs_ids then abs
     else reorder_in_fresh_abs abs
   in
 
-  let env = C.env_map_abs reorder_in_abs ctx.env in
+  let env = env_map_abs reorder_in_abs ctx.env in
 
-  { ctx with C.env }
+  { ctx with env }
 
-let prepare_ashared_loans (loop_id : V.LoopId.id option) : cm_fun =
+let prepare_ashared_loans (loop_id : LoopId.id option) : cm_fun =
  fun cf ctx0 ->
   let ctx = ctx0 in
   (* Compute the set of borrows which appear in the abstractions, so that
@@ -85,7 +79,7 @@ let prepare_ashared_loans (loop_id : V.LoopId.id option) : cm_fun =
   *)
   let absl =
     List.filter_map
-      (function C.Var _ | C.Frame -> None | C.Abs abs -> Some abs)
+      (function EBinding _ | EFrame -> None | EAbs abs -> Some abs)
       ctx.env
   in
   let absl_ids, absl_id_maps = compute_absl_ids absl in
@@ -100,19 +94,18 @@ let prepare_ashared_loans (loop_id : V.LoopId.id option) : cm_fun =
      - the region ids found in the value and belonging to the set [rids] have
        been substituted with [nrid]
   *)
-  let mk_value_with_fresh_sids_no_shared_loans (rids : T.RegionId.Set.t)
-      (nrid : T.RegionId.id) (v : V.typed_value) : V.typed_value =
+  let mk_value_with_fresh_sids_no_shared_loans (rids : RegionId.Set.t)
+      (nrid : RegionId.id) (v : typed_value) : typed_value =
     (* Remove the shared loans *)
     let v = value_remove_shared_loans v in
     (* Substitute the symbolic values and the region *)
-    Subst.typed_value_subst_ids
-      (fun r -> if T.RegionId.Set.mem r rids then nrid else r)
-      (fun x -> x)
+    Substitute.typed_value_subst_ids
+      (fun r -> if RegionId.Set.mem r rids then nrid else r)
       (fun x -> x)
       (fun x -> x)
       (fun id ->
-        let nid = C.fresh_symbolic_value_id () in
-        let sv = V.SymbolicValueId.Map.find id absl_id_maps.sids_to_values in
+        let nid = fresh_symbolic_value_id () in
+        let sv = SymbolicValueId.Map.find id absl_id_maps.sids_to_values in
         sid_subst := (nid, sv) :: !sid_subst;
         nid)
       (fun x -> x)
@@ -143,13 +136,13 @@ let prepare_ashared_loans (loop_id : V.LoopId.id option) : cm_fun =
        abs'2 { SB l0, SL {l2} s2 }
      ]}
   *)
-  let push_abs_for_shared_value (abs : V.abs) (sv : V.typed_value)
-      (lid : V.BorrowId.id) : unit =
+  let push_abs_for_shared_value (abs : abs) (sv : typed_value)
+      (lid : BorrowId.id) : unit =
     (* Create a fresh borrow (for the reborrow) *)
-    let nlid = C.fresh_borrow_id () in
+    let nlid = fresh_borrow_id () in
 
     (* We need a fresh region for the new abstraction *)
-    let nrid = C.fresh_region_id () in
+    let nrid = fresh_region_id () in
 
     (* Prepare the shared value *)
     let nsv = mk_value_with_fresh_sids_no_shared_loans abs.regions nrid sv in
@@ -158,46 +151,47 @@ let prepare_ashared_loans (loop_id : V.LoopId.id option) : cm_fun =
     borrow_substs := (lid, nlid) :: !borrow_substs;
 
     (* Rem.: the below sanity checks are not really necessary *)
-    assert (V.AbstractionId.Set.is_empty abs.parents);
+    assert (AbstractionId.Set.is_empty abs.parents);
     assert (abs.original_parents = []);
-    assert (T.RegionId.Set.is_empty abs.ancestors_regions);
+    assert (RegionId.Set.is_empty abs.ancestors_regions);
 
     (* Introduce the new abstraction for the shared values *)
-    let rty = ety_no_regions_to_rty sv.V.ty in
+    assert (ty_no_regions sv.ty);
+    let rty = sv.ty in
 
     (* Create the shared loan child *)
     let child_rty = rty in
     let child_av = mk_aignored child_rty in
 
     (* Create the shared loan *)
-    let loan_rty = T.Ref (T.Var nrid, rty, T.Shared) in
+    let loan_rty = TRef (RVar nrid, rty, RShared) in
     let loan_value =
-      V.ALoan (V.ASharedLoan (V.BorrowId.Set.singleton nlid, nsv, child_av))
+      ALoan (ASharedLoan (BorrowId.Set.singleton nlid, nsv, child_av))
     in
     let loan_value = mk_typed_avalue loan_rty loan_value in
 
     (* Create the shared borrow *)
     let borrow_rty = loan_rty in
-    let borrow_value = V.ABorrow (V.ASharedBorrow lid) in
+    let borrow_value = ABorrow (ASharedBorrow lid) in
     let borrow_value = mk_typed_avalue borrow_rty borrow_value in
 
     (* Create the abstraction *)
     let avalues = [ borrow_value; loan_value ] in
-    let kind =
+    let kind : abs_kind =
       match loop_id with
-      | Some loop_id -> V.Loop (loop_id, None, V.LoopSynthInput)
-      | None -> V.Identity
+      | Some loop_id -> Loop (loop_id, None, LoopSynthInput)
+      | None -> Identity
     in
     let can_end = true in
     let fresh_abs =
       {
-        V.abs_id = C.fresh_abstraction_id ();
+        abs_id = fresh_abstraction_id ();
         kind;
         can_end;
-        parents = V.AbstractionId.Set.empty;
+        parents = AbstractionId.Set.empty;
         original_parents = [];
-        regions = T.RegionId.Set.singleton nrid;
-        ancestors_regions = T.RegionId.Set.empty;
+        regions = RegionId.Set.singleton nrid;
+        ancestors_regions = RegionId.Set.empty;
         avalues;
       }
     in
@@ -210,34 +204,34 @@ let prepare_ashared_loans (loop_id : V.LoopId.id option) : cm_fun =
      We simply explore the context and call {!push_abs_for_shared_value}
      when necessary.
   *)
-  let collect_shared_values_in_abs (abs : V.abs) : unit =
-    let collect_shared_value lids (sv : V.typed_value) =
+  let collect_shared_values_in_abs (abs : abs) : unit =
+    let collect_shared_value lids (sv : typed_value) =
       (* Sanity check: we don't support nested borrows for now *)
-      assert (not (value_has_borrows ctx sv.V.value));
+      assert (not (value_has_borrows ctx sv.value));
 
       (* Filter the loan ids whose corresponding borrows appear in abstractions
          (see the documentation of the function) *)
-      let lids = V.BorrowId.Set.diff lids abs_borrow_ids in
+      let lids = BorrowId.Set.diff lids abs_borrow_ids in
 
       (* Generate fresh borrows and values *)
-      V.BorrowId.Set.iter (push_abs_for_shared_value abs sv) lids
+      BorrowId.Set.iter (push_abs_for_shared_value abs sv) lids
     in
 
     let visit_avalue =
       object
-        inherit [_] V.iter_typed_avalue as super
+        inherit [_] iter_typed_avalue as super
 
-        method! visit_SharedLoan env lids sv =
+        method! visit_VSharedLoan env lids sv =
           collect_shared_value lids sv;
 
           (* Continue the exploration *)
-          super#visit_SharedLoan env lids sv
+          super#visit_VSharedLoan env lids sv
 
-        method! visit_ASharedLoan env lids sv _ =
+        method! visit_ASharedLoan env lids sv av =
           collect_shared_value lids sv;
 
           (* Continue the exploration *)
-          super#visit_SharedLoan env lids sv
+          super#visit_ASharedLoan env lids sv av
 
         (** Check that there are no symbolic values with *borrows* inside the
             abstraction - shouldn't happen if the symbolic values are greedily
@@ -253,7 +247,7 @@ let prepare_ashared_loans (loop_id : V.LoopId.id option) : cm_fun =
     in
     List.iter (visit_avalue#visit_typed_avalue None) abs.avalues
   in
-  C.env_iter_abs collect_shared_values_in_abs ctx.env;
+  env_iter_abs collect_shared_values_in_abs ctx.env;
 
   (* Update the borrow ids in the environment.
 
@@ -287,16 +281,14 @@ let prepare_ashared_loans (loop_id : V.LoopId.id option) : cm_fun =
      ]}
   *)
   let env =
-    let bmap = V.BorrowId.Map.of_list !borrow_substs in
+    let bmap = BorrowId.Map.of_list !borrow_substs in
     let bsusbt bid =
-      match V.BorrowId.Map.find_opt bid bmap with
-      | None -> bid
-      | Some bid -> bid
+      match BorrowId.Map.find_opt bid bmap with None -> bid | Some bid -> bid
     in
 
     let visitor =
       object
-        inherit [_] C.map_env
+        inherit [_] map_env
         method! visit_borrow_id _ bid = bsusbt bid
       end
     in
@@ -304,7 +296,7 @@ let prepare_ashared_loans (loop_id : V.LoopId.id option) : cm_fun =
   in
 
   (* Add the abstractions *)
-  let fresh_absl = List.map (fun abs -> C.Abs abs) !fresh_absl in
+  let fresh_absl = List.map (fun abs -> EAbs abs) !fresh_absl in
   let env = List.append fresh_absl env in
   let ctx = { ctx with env } in
 
@@ -320,18 +312,18 @@ let prepare_ashared_loans (loop_id : V.LoopId.id option) : cm_fun =
            (fun e (sid, v) ->
              let v = mk_typed_value_from_symbolic_value v in
              let sv =
-               V.SymbolicValueId.Map.find sid new_ctx_ids_map.sids_to_values
+               SymbolicValueId.Map.find sid new_ctx_ids_map.sids_to_values
              in
-             SymbolicAst.IntroSymbolic (ctx, None, sv, SingleValue v, e))
+             SymbolicAst.IntroSymbolic (ctx, None, sv, VaSingleValue v, e))
            e !sid_subst)
 
-let prepare_ashared_loans_no_synth (loop_id : V.LoopId.id) (ctx : C.eval_ctx) :
-    C.eval_ctx =
+let prepare_ashared_loans_no_synth (loop_id : LoopId.id) (ctx : eval_ctx) :
+    eval_ctx =
   get_cf_ctx_no_synth (prepare_ashared_loans (Some loop_id)) ctx
 
-let compute_loop_entry_fixed_point (config : C.config) (loop_id : V.LoopId.id)
-    (eval_loop_body : st_cm_fun) (ctx0 : C.eval_ctx) :
-    C.eval_ctx * ids_sets * V.abs T.RegionGroupId.Map.t =
+let compute_loop_entry_fixed_point (config : config) (loop_id : LoopId.id)
+    (eval_loop_body : st_cm_fun) (ctx0 : eval_ctx) :
+    eval_ctx * ids_sets * abs RegionGroupId.Map.t =
   (* The continuation for when we exit the loop - we register the
      environments upon loop *reentry*, and synthesize nothing by
      returning [None]
@@ -384,7 +376,7 @@ let compute_loop_entry_fixed_point (config : C.config) (loop_id : V.LoopId.id)
   (* Join the contexts at the loop entry - ctx1 is the current joined
      context (the context at the loop entry, after we called
      {!prepare_ashared_loans}, if this is the first iteration) *)
-  let join_ctxs (ctx1 : C.eval_ctx) : C.eval_ctx =
+  let join_ctxs (ctx1 : eval_ctx) : eval_ctx =
     (* If this is the first iteration, end the borrows/loans/abs which
        appear in ctx1 and not in the other contexts, then compute the
        set of fixed ids. This means those borrows/loans have to end
@@ -395,8 +387,8 @@ let compute_loop_entry_fixed_point (config : C.config) (loop_id : V.LoopId.id)
       | None ->
           let old_ids, _ = compute_context_ids ctx1 in
           let new_ids, _ = compute_contexts_ids !ctxs in
-          let blids = V.BorrowId.Set.diff old_ids.blids new_ids.blids in
-          let aids = V.AbstractionId.Set.diff old_ids.aids new_ids.aids in
+          let blids = BorrowId.Set.diff old_ids.blids new_ids.blids in
+          let aids = AbstractionId.Set.diff old_ids.aids new_ids.aids in
           (* End those borrows and abstractions *)
           let end_borrows_abs blids aids ctx =
             let ctx =
@@ -431,14 +423,14 @@ let compute_loop_entry_fixed_point (config : C.config) (loop_id : V.LoopId.id)
   (* Compute the set of fixed ids - for the symbolic ids, we compute the
      intersection of ids between the original environment and the list
      of new environments *)
-  let compute_fixed_ids (ctxl : C.eval_ctx list) : ids_sets =
+  let compute_fixed_ids (ctxl : eval_ctx list) : ids_sets =
     let fixed_ids, _ = compute_context_ids ctx0 in
     let { aids; blids; borrow_ids; loan_ids; dids; rids; sids } = fixed_ids in
     let sids = ref sids in
     List.iter
       (fun ctx ->
         let fixed_ids, _ = compute_context_ids ctx in
-        sids := V.SymbolicValueId.Set.inter !sids fixed_ids.sids)
+        sids := SymbolicValueId.Set.inter !sids fixed_ids.sids)
       ctxl;
     let sids = !sids in
     let fixed_ids = { aids; blids; borrow_ids; loan_ids; dids; rids; sids } in
@@ -447,7 +439,7 @@ let compute_loop_entry_fixed_point (config : C.config) (loop_id : V.LoopId.id)
   (* Check if two contexts are equivalent - modulo alpha conversion on the
      existentially quantified borrows/abstractions/symbolic values.
   *)
-  let equiv_ctxs (ctx1 : C.eval_ctx) (ctx2 : C.eval_ctx) : bool =
+  let equiv_ctxs (ctx1 : eval_ctx) (ctx2 : eval_ctx) : bool =
     let fixed_ids = compute_fixed_ids [ ctx1; ctx2 ] in
     let check_equivalent = true in
     let lookup_shared_value _ = raise (Failure "Unreachable") in
@@ -456,8 +448,7 @@ let compute_loop_entry_fixed_point (config : C.config) (loop_id : V.LoopId.id)
          lookup_shared_value ctx1 ctx2)
   in
   let max_num_iter = Config.loop_fixed_point_max_num_iters in
-  let rec compute_fixed_point (ctx : C.eval_ctx) (i0 : int) (i : int) :
-      C.eval_ctx =
+  let rec compute_fixed_point (ctx : eval_ctx) (i0 : int) (i : int) : eval_ctx =
     if i = 0 then
       raise
         (Failure
@@ -502,17 +493,17 @@ let compute_loop_entry_fixed_point (config : C.config) (loop_id : V.LoopId.id)
   *)
   let fp, rg_to_abs =
     (* List the loop abstractions in the fixed-point *)
-    let fp_aids, add_aid, _mem_aid = V.AbstractionId.Set.mk_stateful_set () in
+    let fp_aids, add_aid, _mem_aid = AbstractionId.Set.mk_stateful_set () in
 
     let list_loop_abstractions =
       object
-        inherit [_] C.map_eval_ctx
+        inherit [_] map_eval_ctx
 
         method! visit_abs _ abs =
           match abs.kind with
           | Loop (loop_id', _, kind) ->
               assert (loop_id' = loop_id);
-              assert (kind = V.LoopSynthInput);
+              assert (kind = LoopSynthInput);
               (* The abstractions introduced so far should be endable *)
               assert (abs.can_end = true);
               add_aid abs.abs_id;
@@ -529,15 +520,14 @@ let compute_loop_entry_fixed_point (config : C.config) (loop_id : V.LoopId.id)
      *
      * [fp_ended_aids] links region groups to sets of ended abstractions.
      *)
-    let fp_ended_aids = ref T.RegionGroupId.Map.empty in
-    let add_ended_aids (rg_id : T.RegionGroupId.id)
-        (aids : V.AbstractionId.Set.t) : unit =
-      match T.RegionGroupId.Map.find_opt rg_id !fp_ended_aids with
-      | None ->
-          fp_ended_aids := T.RegionGroupId.Map.add rg_id aids !fp_ended_aids
+    let fp_ended_aids = ref RegionGroupId.Map.empty in
+    let add_ended_aids (rg_id : RegionGroupId.id) (aids : AbstractionId.Set.t) :
+        unit =
+      match RegionGroupId.Map.find_opt rg_id !fp_ended_aids with
+      | None -> fp_ended_aids := RegionGroupId.Map.add rg_id aids !fp_ended_aids
       | Some aids' ->
-          let aids = V.AbstractionId.Set.union aids aids' in
-          fp_ended_aids := T.RegionGroupId.Map.add rg_id aids !fp_ended_aids
+          let aids = AbstractionId.Set.union aids aids' in
+          fp_ended_aids := RegionGroupId.Map.add rg_id aids !fp_ended_aids
     in
     let cf_loop : st_m_fun =
      fun res ctx ->
@@ -566,20 +556,20 @@ let compute_loop_entry_fixed_point (config : C.config) (loop_id : V.LoopId.id)
                    abstractions should have been introduced in a specific
                    order (and we check that it is indeed the case) *)
                 let abs_id =
-                  V.AbstractionId.of_int (T.RegionGroupId.to_int rg_id)
+                  AbstractionId.of_int (RegionGroupId.to_int rg_id)
                 in
                 (* By default, the [SynthInput] abs can't end *)
-                let ctx = C.ctx_set_abs_can_end ctx abs_id true in
+                let ctx = ctx_set_abs_can_end ctx abs_id true in
                 assert (
-                  let abs = C.ctx_lookup_abs ctx abs_id in
-                  abs.kind = V.SynthInput rg_id);
+                  let abs = ctx_lookup_abs ctx abs_id in
+                  abs.kind = SynthInput rg_id);
                 (* End this abstraction *)
                 let ctx =
                   InterpreterBorrows.end_abstraction_no_synth config abs_id ctx
                 in
                 (* Explore the context, and check which abstractions are not there anymore *)
                 let ids, _ = compute_context_ids ctx in
-                let ended_ids = V.AbstractionId.Set.diff !fp_aids ids.aids in
+                let ended_ids = AbstractionId.Set.diff !fp_aids ids.aids in
                 add_ended_aids rg_id ended_ids)
               ctx.region_groups
           in
@@ -590,27 +580,27 @@ let compute_loop_entry_fixed_point (config : C.config) (loop_id : V.LoopId.id)
 
     (* Check that the sets of abstractions we need to end per region group are pairwise
      * disjoint *)
-    let aids_union = ref V.AbstractionId.Set.empty in
+    let aids_union = ref AbstractionId.Set.empty in
     let _ =
-      T.RegionGroupId.Map.iter
+      RegionGroupId.Map.iter
         (fun _ ids ->
-          assert (V.AbstractionId.Set.disjoint !aids_union ids);
-          aids_union := V.AbstractionId.Set.union ids !aids_union)
+          assert (AbstractionId.Set.disjoint !aids_union ids);
+          aids_union := AbstractionId.Set.union ids !aids_union)
         !fp_ended_aids
     in
 
     (* We also check that all the regions need to end - this is not necessary per
        se, but if it doesn't happen it is bizarre and worth investigating... *)
-    assert (V.AbstractionId.Set.equal !aids_union !fp_aids);
+    assert (AbstractionId.Set.equal !aids_union !fp_aids);
 
     (* Merge the abstractions which need to be merged, and compute the map from
        region id to abstraction id *)
     let fp = ref fp in
-    let rg_to_abs = ref T.RegionGroupId.Map.empty in
+    let rg_to_abs = ref RegionGroupId.Map.empty in
     let _ =
-      T.RegionGroupId.Map.iter
+      RegionGroupId.Map.iter
         (fun rg_id ids ->
-          let ids = V.AbstractionId.Set.elements ids in
+          let ids = AbstractionId.Set.elements ids in
           (* Retrieve the first id of the group *)
           match ids with
           | [] ->
@@ -623,10 +613,12 @@ let compute_loop_entry_fixed_point (config : C.config) (loop_id : V.LoopId.id)
           | id0 :: ids ->
               let id0 = ref id0 in
               (* Add the proper region group into the abstraction *)
-              let abs_kind = V.Loop (loop_id, Some rg_id, V.LoopSynthInput) in
-              let abs = C.ctx_lookup_abs !fp !id0 in
-              let abs = { abs with V.kind = abs_kind } in
-              let fp', _ = C.ctx_subst_abs !fp !id0 abs in
+              let abs_kind : abs_kind =
+                Loop (loop_id, Some rg_id, LoopSynthInput)
+              in
+              let abs = ctx_lookup_abs !fp !id0 in
+              let abs = { abs with kind = abs_kind } in
+              let fp', _ = ctx_subst_abs !fp !id0 abs in
               fp := fp';
               (* Merge all the abstractions into this one *)
               List.iter
@@ -635,10 +627,8 @@ let compute_loop_entry_fixed_point (config : C.config) (loop_id : V.LoopId.id)
                     log#ldebug
                       (lazy
                         ("compute_loop_entry_fixed_point: merge FP \
-                          abstraction: "
-                        ^ V.AbstractionId.to_string id
-                        ^ " into "
-                        ^ V.AbstractionId.to_string !id0));
+                          abstraction: " ^ AbstractionId.to_string id ^ " into "
+                        ^ AbstractionId.to_string !id0));
                     (* Note that we merge *into* [id0] *)
                     let fp', id0' =
                       merge_into_abstraction loop_id abs_kind false !fp id !id0
@@ -649,8 +639,8 @@ let compute_loop_entry_fixed_point (config : C.config) (loop_id : V.LoopId.id)
                   with ValueMatchFailure _ -> raise (Failure "Unexpected"))
                 ids;
               (* Register the mapping *)
-              let abs = C.ctx_lookup_abs !fp !id0 in
-              rg_to_abs := T.RegionGroupId.Map.add_strict rg_id abs !rg_to_abs)
+              let abs = ctx_lookup_abs !fp !id0 in
+              rg_to_abs := RegionGroupId.Map.add_strict rg_id abs !rg_to_abs)
         !fp_ended_aids
     in
     let rg_to_abs = !rg_to_abs in
@@ -674,15 +664,15 @@ let compute_loop_entry_fixed_point (config : C.config) (loop_id : V.LoopId.id)
     *)
     let update_loop_abstractions (remove_rg_id : bool) =
       object
-        inherit [_] C.map_eval_ctx
+        inherit [_] map_eval_ctx
 
         method! visit_abs _ abs =
           match abs.kind with
           | Loop (loop_id', _, kind) ->
               assert (loop_id' = loop_id);
-              assert (kind = V.LoopSynthInput);
-              let kind =
-                if remove_rg_id then V.Loop (loop_id, None, V.LoopSynthInput)
+              assert (kind = LoopSynthInput);
+              let kind : abs_kind =
+                if remove_rg_id then Loop (loop_id, None, LoopSynthInput)
                 else abs.kind
               in
               { abs with can_end = remove_rg_id; kind }
@@ -715,7 +705,7 @@ let compute_loop_entry_fixed_point (config : C.config) (loop_id : V.LoopId.id)
   (fp, fixed_ids, rg_to_abs)
 
 let compute_fixed_point_id_correspondance (fixed_ids : ids_sets)
-    (src_ctx : C.eval_ctx) (tgt_ctx : C.eval_ctx) : borrow_loan_corresp =
+    (src_ctx : eval_ctx) (tgt_ctx : eval_ctx) : borrow_loan_corresp =
   log#ldebug
     (lazy
       ("compute_fixed_point_id_correspondance:\n\n- fixed_ids:\n"
@@ -741,10 +731,10 @@ let compute_fixed_point_id_correspondance (fixed_ids : ids_sets)
     let check_equiv = false in
     let fixed_ids = ids_sets_empty_borrows_loans fixed_ids in
     let open InterpreterBorrowsCore in
-    let lookup_shared_loan lid ctx : V.typed_value =
+    let lookup_shared_loan lid ctx : typed_value =
       match snd (lookup_loan ek_all lid ctx) with
-      | Concrete (V.SharedLoan (_, v)) -> v
-      | Abstract (V.ASharedLoan (_, v, _)) -> v
+      | Concrete (VSharedLoan (_, v)) -> v
+      | Abstract (ASharedLoan (_, v, _)) -> v
       | _ -> raise (Failure "Unreachable")
     in
     let lookup_in_tgt id = lookup_shared_loan id tgt_ctx in
@@ -760,10 +750,10 @@ let compute_fixed_point_id_correspondance (fixed_ids : ids_sets)
      ^ show_ids_maps maps ^ "\n\n"));
 
   let src_to_tgt_borrow_map =
-    V.BorrowId.Map.of_list
+    BorrowId.Map.of_list
       (List.map
          (fun (x, y) -> (y, x))
-         (V.BorrowId.InjSubst.bindings maps.borrow_id_map))
+         (BorrowId.InjSubst.bindings maps.borrow_id_map))
   in
 
   (* Sanity check: for every abstraction, the target loans and borrows are mapped
@@ -800,12 +790,12 @@ let compute_fixed_point_id_correspondance (fixed_ids : ids_sets)
       let ids, _ = compute_abs_ids abs in
       (* Map the *loan* ids (we just match the corresponding *loans* ) *)
       let loan_ids =
-        V.BorrowId.Set.map
-          (fun x -> V.BorrowId.InjSubst.find x maps.borrow_id_map)
+        BorrowId.Set.map
+          (fun x -> BorrowId.InjSubst.find x maps.borrow_id_map)
           ids.loan_ids
       in
       (* Check that the loan and borrows are related *)
-      assert (V.BorrowId.Set.equal ids.borrow_ids loan_ids))
+      assert (BorrowId.Set.equal ids.borrow_ids loan_ids))
     new_absl;
 
   (* For every target abstraction (going back to the [list_nth_mut] example,
@@ -819,27 +809,27 @@ let compute_fixed_point_id_correspondance (fixed_ids : ids_sets)
      if it actually corresponds to a borrows introduced when decomposing the
      abstractions to move the shared values out of the source context abstractions.
   *)
-  let tgt_borrow_to_loan = ref V.BorrowId.InjSubst.empty in
+  let tgt_borrow_to_loan = ref BorrowId.InjSubst.empty in
   let visit_tgt =
     object
-      inherit [_] V.iter_abs
+      inherit [_] iter_abs
 
       method! visit_borrow_id _ id =
         (* Find the target borrow *)
-        let tgt_borrow_id = V.BorrowId.Map.find id src_to_tgt_borrow_map in
+        let tgt_borrow_id = BorrowId.Map.find id src_to_tgt_borrow_map in
         (* Update the map *)
         tgt_borrow_to_loan :=
-          V.BorrowId.InjSubst.add id tgt_borrow_id !tgt_borrow_to_loan
+          BorrowId.InjSubst.add id tgt_borrow_id !tgt_borrow_to_loan
     end
   in
   List.iter (visit_tgt#visit_abs ()) new_absl;
 
   (* Compute the map from loan to borrows *)
   let tgt_loan_to_borrow =
-    V.BorrowId.InjSubst.of_list
+    BorrowId.InjSubst.of_list
       (List.map
          (fun (x, y) -> (y, x))
-         (V.BorrowId.InjSubst.bindings !tgt_borrow_to_loan))
+         (BorrowId.InjSubst.bindings !tgt_borrow_to_loan))
   in
 
   (* Return *)
@@ -848,11 +838,11 @@ let compute_fixed_point_id_correspondance (fixed_ids : ids_sets)
     loan_to_borrow_id_map = tgt_loan_to_borrow;
   }
 
-let compute_fp_ctx_symbolic_values (ctx : C.eval_ctx) (fp_ctx : C.eval_ctx) :
-    V.SymbolicValueId.Set.t * V.symbolic_value list =
+let compute_fp_ctx_symbolic_values (ctx : eval_ctx) (fp_ctx : eval_ctx) :
+    SymbolicValueId.Set.t * symbolic_value list =
   let old_ids, _ = compute_context_ids ctx in
   let fp_ids, fp_ids_maps = compute_context_ids fp_ctx in
-  let fresh_sids = V.SymbolicValueId.Set.diff fp_ids.sids old_ids.sids in
+  let fresh_sids = SymbolicValueId.Set.diff fp_ids.sids old_ids.sids in
 
   (* Compute the set of symbolic values which appear in shared values inside
      *fixed* abstractions: because we introduce fresh abstractions and reborrows
@@ -863,10 +853,10 @@ let compute_fp_ctx_symbolic_values (ctx : C.eval_ctx) (fp_ctx : C.eval_ctx) :
   let shared_sids_in_fixed_abs =
     let fixed_absl =
       List.filter
-        (fun (ee : C.env_elem) ->
+        (fun (ee : env_elem) ->
           match ee with
-          | C.Var _ | C.Frame -> false
-          | Abs abs -> V.AbstractionId.Set.mem abs.abs_id old_ids.aids)
+          | EBinding _ | EFrame -> false
+          | EAbs abs -> AbstractionId.Set.mem abs.abs_id old_ids.aids)
         ctx.env
     in
 
@@ -876,17 +866,17 @@ let compute_fp_ctx_symbolic_values (ctx : C.eval_ctx) (fp_ctx : C.eval_ctx) :
        shared values. We prefer to be more general, in prevision of later
        changes.
     *)
-    let sids = ref V.SymbolicValueId.Set.empty in
+    let sids = ref SymbolicValueId.Set.empty in
     let visitor =
       object (self)
-        inherit [_] C.iter_env
+        inherit [_] iter_env
 
         method! visit_ASharedLoan inside_shared _ sv child_av =
           self#visit_typed_value true sv;
           self#visit_typed_avalue inside_shared child_av
 
         method! visit_symbolic_value_id inside_shared sid =
-          if inside_shared then sids := V.SymbolicValueId.Set.add sid !sids
+          if inside_shared then sids := SymbolicValueId.Set.add sid !sids
       end
     in
     visitor#visit_env false fixed_absl;
@@ -900,15 +890,14 @@ let compute_fp_ctx_symbolic_values (ctx : C.eval_ctx) (fp_ctx : C.eval_ctx) :
   log#ldebug
     (lazy
       ("compute_fp_ctx_symbolic_values:" ^ "\n- shared_sids_in_fixed_abs:"
-      ^ V.SymbolicValueId.Set.show shared_sids_in_fixed_abs
+      ^ SymbolicValueId.Set.show shared_sids_in_fixed_abs
       ^ "\n- all_sids_to_values: "
-      ^ V.SymbolicValueId.Map.show (symbolic_value_to_string ctx) sids_to_values
+      ^ SymbolicValueId.Map.show (symbolic_value_to_string ctx) sids_to_values
       ^ "\n"));
 
   let sids_to_values =
-    V.SymbolicValueId.Map.filter
-      (fun sid _ ->
-        not (V.SymbolicValueId.Set.mem sid shared_sids_in_fixed_abs))
+    SymbolicValueId.Map.filter
+      (fun sid _ -> not (SymbolicValueId.Set.mem sid shared_sids_in_fixed_abs))
       sids_to_values
   in
 
@@ -919,27 +908,27 @@ let compute_fp_ctx_symbolic_values (ctx : C.eval_ctx) (fp_ctx : C.eval_ctx) :
      variable [x] which appears before [y] are listed first, for instance.
   *)
   let input_svalues =
-    let found_sids = ref V.SymbolicValueId.Set.empty in
+    let found_sids = ref SymbolicValueId.Set.empty in
     let ordered_sids = ref [] in
 
     let visitor =
       object (self)
-        inherit [_] C.iter_env
+        inherit [_] iter_env
 
         (** We lookup the shared values *)
-        method! visit_SharedBorrow env bid =
+        method! visit_VSharedBorrow env bid =
           let open InterpreterBorrowsCore in
           let v =
             match snd (lookup_loan ek_all bid fp_ctx) with
-            | Concrete (V.SharedLoan (_, v)) -> v
-            | Abstract (V.ASharedLoan (_, v, _)) -> v
+            | Concrete (VSharedLoan (_, v)) -> v
+            | Abstract (ASharedLoan (_, v, _)) -> v
             | _ -> raise (Failure "Unreachable")
           in
           self#visit_typed_value env v
 
         method! visit_symbolic_value_id _ id =
-          if not (V.SymbolicValueId.Set.mem id !found_sids) then (
-            found_sids := V.SymbolicValueId.Set.add id !found_sids;
+          if not (SymbolicValueId.Set.mem id !found_sids) then (
+            found_sids := SymbolicValueId.Set.add id !found_sids;
             ordered_sids := id :: !ordered_sids)
       end
     in
@@ -947,7 +936,7 @@ let compute_fp_ctx_symbolic_values (ctx : C.eval_ctx) (fp_ctx : C.eval_ctx) :
     List.iter (visitor#visit_env_elem ()) (List.rev fp_ctx.env);
 
     List.filter_map
-      (fun id -> V.SymbolicValueId.Map.find_opt id sids_to_values)
+      (fun id -> SymbolicValueId.Map.find_opt id sids_to_values)
       (List.rev !ordered_sids)
   in
 
@@ -958,7 +947,7 @@ let compute_fp_ctx_symbolic_values (ctx : C.eval_ctx) (fp_ctx : C.eval_ctx) :
       ^ "\n- fixed point:\n"
       ^ eval_ctx_to_string_no_filter fp_ctx
       ^ "\n- fresh_sids: "
-      ^ V.SymbolicValueId.Set.show fresh_sids
+      ^ SymbolicValueId.Set.show fresh_sids
       ^ "\n- input_svalues: "
       ^ Print.list_to_string (symbolic_value_to_string ctx) input_svalues
       ^ "\n\n"));
diff --git a/compiler/InterpreterLoopsFixedPoint.mli b/compiler/InterpreterLoopsFixedPoint.mli
index cb03bc9e..65a76359 100644
--- a/compiler/InterpreterLoopsFixedPoint.mli
+++ b/compiler/InterpreterLoopsFixedPoint.mli
@@ -1,13 +1,5 @@
-module T = Types
-module PV = PrimitiveValues
-module V = Values
-module E = Expressions
-module C = Contexts
-module Subst = Substitute
-module A = LlbcAst
-module L = Logging
-module Inv = Invariants
-module S = SynthesizeSymbolic
+open Values
+open Contexts
 open InterpreterUtils
 open InterpreterLoopsCore
 
@@ -56,7 +48,7 @@ open InterpreterLoopsCore
 
     we only introduce a fresh abstraction for [l1].
   *)
-val prepare_ashared_loans : V.loop_id option -> Cps.cm_fun
+val prepare_ashared_loans : loop_id option -> Cps.cm_fun
 
 (** Compute a fixed-point for the context at the entry of the loop.
     We also return:
@@ -71,11 +63,11 @@ val prepare_ashared_loans : V.loop_id option -> Cps.cm_fun
     the values which are read or modified (some symbolic values may be ignored).
  *)
 val compute_loop_entry_fixed_point :
-  C.config ->
-  V.loop_id ->
+  config ->
+  loop_id ->
   Cps.st_cm_fun ->
-  C.eval_ctx ->
-  C.eval_ctx * ids_sets * V.abs SymbolicAst.region_group_id_map
+  eval_ctx ->
+  eval_ctx * ids_sets * abs SymbolicAst.region_group_id_map
 
 (** For the abstractions in the fixed point, compute the correspondance between
     the borrows ids and the loans ids, if we want to introduce equivalent
@@ -154,7 +146,7 @@ val compute_loop_entry_fixed_point :
     through the loan [l1] is actually the value which has to be given back to [l0].
  *)
 val compute_fixed_point_id_correspondance :
-  ids_sets -> C.eval_ctx -> C.eval_ctx -> borrow_loan_corresp
+  ids_sets -> eval_ctx -> eval_ctx -> borrow_loan_corresp
 
 (** Compute the set of "quantified" symbolic value ids in a fixed-point context.
 
@@ -163,4 +155,4 @@ val compute_fixed_point_id_correspondance :
     - the list of input symbolic values
  *)
 val compute_fp_ctx_symbolic_values :
-  C.eval_ctx -> C.eval_ctx -> V.symbolic_value_id_set * V.symbolic_value list
+  eval_ctx -> eval_ctx -> symbolic_value_id_set * symbolic_value list
diff --git a/compiler/InterpreterLoopsJoinCtxs.ml b/compiler/InterpreterLoopsJoinCtxs.ml
index 6d3ecb18..4cc74aae 100644
--- a/compiler/InterpreterLoopsJoinCtxs.ml
+++ b/compiler/InterpreterLoopsJoinCtxs.ml
@@ -1,23 +1,15 @@
-module T = Types
-module PV = PrimitiveValues
-module V = Values
-module E = Expressions
-module C = Contexts
-module Subst = Substitute
-module A = LlbcAst
-module L = Logging
+open Types
+open Values
+open Contexts
 open TypesUtils
 open ValuesUtils
-module Inv = Invariants
-module S = SynthesizeSymbolic
-module UF = UnionFind
 open InterpreterUtils
 open InterpreterBorrows
 open InterpreterLoopsCore
 open InterpreterLoopsMatchCtxs
 
 (** The local logger *)
-let log = L.loops_join_ctxs_log
+let log = Logging.loops_join_ctxs_log
 
 (** Reorder the loans and borrows in the fresh abstractions.
 
@@ -26,17 +18,17 @@ let log = L.loops_join_ctxs_log
     called typically after we merge abstractions together (see {!collapse_ctx}
     for instance).
  *)
-let reorder_loans_borrows_in_fresh_abs (old_abs_ids : V.AbstractionId.Set.t)
-    (ctx : C.eval_ctx) : C.eval_ctx =
-  let reorder_in_fresh_abs (abs : V.abs) : V.abs =
+let reorder_loans_borrows_in_fresh_abs (old_abs_ids : AbstractionId.Set.t)
+    (ctx : eval_ctx) : eval_ctx =
+  let reorder_in_fresh_abs (abs : abs) : abs =
     (* Split between the loans and borrows *)
-    let is_borrow (av : V.typed_avalue) : bool =
-      match av.V.value with
+    let is_borrow (av : typed_avalue) : bool =
+      match av.value with
       | ABorrow _ -> true
       | ALoan _ -> false
       | _ -> raise (Failure "Unexpected")
     in
-    let aborrows, aloans = List.partition is_borrow abs.V.avalues in
+    let aborrows, aloans = List.partition is_borrow abs.avalues in
 
     (* Reoder the borrows, and the loans.
 
@@ -44,38 +36,38 @@ let reorder_loans_borrows_in_fresh_abs (old_abs_ids : V.AbstractionId.Set.t)
        and the borrows to find fixed points is simply to sort them by increasing
        order of id (taking the smallest id of a set of ids, in case of sets).
     *)
-    let get_borrow_id (av : V.typed_avalue) : V.BorrowId.id =
-      match av.V.value with
-      | V.ABorrow (V.AMutBorrow (bid, _) | V.ASharedBorrow bid) -> bid
+    let get_borrow_id (av : typed_avalue) : BorrowId.id =
+      match av.value with
+      | ABorrow (AMutBorrow (bid, _) | ASharedBorrow bid) -> bid
       | _ -> raise (Failure "Unexpected")
     in
-    let get_loan_id (av : V.typed_avalue) : V.BorrowId.id =
-      match av.V.value with
-      | V.ALoan (V.AMutLoan (lid, _)) -> lid
-      | V.ALoan (V.ASharedLoan (lids, _, _)) -> V.BorrowId.Set.min_elt lids
+    let get_loan_id (av : typed_avalue) : BorrowId.id =
+      match av.value with
+      | ALoan (AMutLoan (lid, _)) -> lid
+      | ALoan (ASharedLoan (lids, _, _)) -> BorrowId.Set.min_elt lids
       | _ -> raise (Failure "Unexpected")
     in
     (* We use ordered maps to reorder the borrows and loans *)
-    let reorder (get_bid : V.typed_avalue -> V.BorrowId.id)
-        (values : V.typed_avalue list) : V.typed_avalue list =
+    let reorder (get_bid : typed_avalue -> BorrowId.id)
+        (values : typed_avalue list) : typed_avalue list =
       List.map snd
-        (V.BorrowId.Map.bindings
-           (V.BorrowId.Map.of_list (List.map (fun v -> (get_bid v, v)) values)))
+        (BorrowId.Map.bindings
+           (BorrowId.Map.of_list (List.map (fun v -> (get_bid v, v)) values)))
     in
     let aborrows = reorder get_borrow_id aborrows in
     let aloans = reorder get_loan_id aloans in
     let avalues = List.append aborrows aloans in
-    { abs with V.avalues }
+    { abs with avalues }
   in
 
-  let reorder_in_abs (abs : V.abs) =
-    if V.AbstractionId.Set.mem abs.abs_id old_abs_ids then abs
+  let reorder_in_abs (abs : abs) =
+    if AbstractionId.Set.mem abs.abs_id old_abs_ids then abs
     else reorder_in_fresh_abs abs
   in
 
-  let env = C.env_map_abs reorder_in_abs ctx.env in
+  let env = env_map_abs reorder_in_abs ctx.env in
 
-  { ctx with C.env }
+  { ctx with env }
 
 (** Collapse an environment.
 
@@ -136,23 +128,23 @@ let reorder_loans_borrows_in_fresh_abs (old_abs_ids : V.AbstractionId.Set.t)
     This can happen when merging environments (note that such environments are not well-formed -
     they become well formed again after collapsing).
  *)
-let collapse_ctx (loop_id : V.LoopId.id)
+let collapse_ctx (loop_id : LoopId.id)
     (merge_funs : merge_duplicates_funcs option) (old_ids : ids_sets)
-    (ctx0 : C.eval_ctx) : C.eval_ctx =
+    (ctx0 : eval_ctx) : eval_ctx =
   (* Debug *)
   log#ldebug
     (lazy
       ("collapse_ctx:\n\n- fixed_ids:\n" ^ show_ids_sets old_ids
      ^ "\n\n- ctx0:\n" ^ eval_ctx_to_string ctx0 ^ "\n\n"));
 
-  let abs_kind = V.Loop (loop_id, None, LoopSynthInput) in
+  let abs_kind : abs_kind = Loop (loop_id, None, LoopSynthInput) in
   let can_end = true in
   let destructure_shared_values = true in
-  let is_fresh_abs_id (id : V.AbstractionId.id) : bool =
-    not (V.AbstractionId.Set.mem id old_ids.aids)
+  let is_fresh_abs_id (id : AbstractionId.id) : bool =
+    not (AbstractionId.Set.mem id old_ids.aids)
   in
-  let is_fresh_did (id : C.DummyVarId.id) : bool =
-    not (C.DummyVarId.Set.mem id old_ids.dids)
+  let is_fresh_did (id : DummyVarId.id) : bool =
+    not (DummyVarId.Set.mem id old_ids.dids)
   in
   (* Convert the dummy values to abstractions (note that when we convert
      values to abstractions, the resulting abstraction should be destructured) *)
@@ -163,18 +155,18 @@ let collapse_ctx (loop_id : V.LoopId.id)
       (List.map
          (fun ee ->
            match ee with
-           | C.Abs _ | C.Frame | C.Var (VarBinder _, _) -> [ ee ]
-           | C.Var (DummyBinder id, v) ->
+           | EAbs _ | EFrame | EBinding (BVar _, _) -> [ ee ]
+           | EBinding (BDummy id, v) ->
                if is_fresh_did id then
                  let absl =
                    convert_value_to_abstractions abs_kind can_end
                      destructure_shared_values ctx0 v
                  in
-                 List.map (fun abs -> C.Abs abs) absl
+                 List.map (fun abs -> EAbs abs) absl
                else [ ee ])
          ctx0.env)
   in
-  let ctx = { ctx0 with C.env } in
+  let ctx = { ctx0 with env } in
   log#ldebug
     (lazy
       ("collapse_ctx: after converting values to abstractions:\n"
@@ -188,7 +180,7 @@ let collapse_ctx (loop_id : V.LoopId.id)
       ));
 
   (* Explore all the *new* abstractions, and compute various maps *)
-  let explore (abs : V.abs) = is_fresh_abs_id abs.abs_id in
+  let explore (abs : abs) = is_fresh_abs_id abs.abs_id in
   let ids_maps =
     compute_abs_borrows_loans_maps (merge_funs = None) explore env
   in
@@ -211,8 +203,9 @@ let collapse_ctx (loop_id : V.LoopId.id)
   in
 
   (* Merge the abstractions together *)
-  let merged_abs : V.AbstractionId.id UF.elem V.AbstractionId.Map.t =
-    V.AbstractionId.Map.of_list (List.map (fun id -> (id, UF.make id)) abs_ids)
+  let merged_abs : AbstractionId.id UnionFind.elem AbstractionId.Map.t =
+    AbstractionId.Map.of_list
+      (List.map (fun id -> (id, UnionFind.make id)) abs_ids)
   in
 
   let ctx = ref ctx in
@@ -226,26 +219,26 @@ let collapse_ctx (loop_id : V.LoopId.id)
   *)
   List.iter
     (fun abs_id0 ->
-      let bids = V.AbstractionId.Map.find abs_id0 abs_to_borrows in
-      let bids = V.BorrowId.Set.elements bids in
+      let bids = AbstractionId.Map.find abs_id0 abs_to_borrows in
+      let bids = BorrowId.Set.elements bids in
       List.iter
         (fun bid ->
-          match V.BorrowId.Map.find_opt bid loan_to_abs with
+          match BorrowId.Map.find_opt bid loan_to_abs with
           | None -> (* Nothing to do *) ()
           | Some abs_ids1 ->
-              V.AbstractionId.Set.iter
+              AbstractionId.Set.iter
                 (fun abs_id1 ->
                   (* We need to merge - unless we have already merged *)
                   (* First, find the representatives for the two abstractions (the
                      representative is the abstraction into which we merged) *)
                   let abs_ref0 =
-                    UF.find (V.AbstractionId.Map.find abs_id0 merged_abs)
+                    UnionFind.find (AbstractionId.Map.find abs_id0 merged_abs)
                   in
-                  let abs_id0 = UF.get abs_ref0 in
+                  let abs_id0 = UnionFind.get abs_ref0 in
                   let abs_ref1 =
-                    UF.find (V.AbstractionId.Map.find abs_id1 merged_abs)
+                    UnionFind.find (AbstractionId.Map.find abs_id1 merged_abs)
                   in
-                  let abs_id1 = UF.get abs_ref1 in
+                  let abs_id1 = UnionFind.get abs_ref1 in
                   (* If the two ids are the same, it means the abstractions were already merged *)
                   if abs_id0 = abs_id1 then ()
                   else (
@@ -255,9 +248,9 @@ let collapse_ctx (loop_id : V.LoopId.id)
                     log#ldebug
                       (lazy
                         ("collapse_ctx: merging abstraction "
-                        ^ V.AbstractionId.to_string abs_id1
+                        ^ AbstractionId.to_string abs_id1
                         ^ " into "
-                        ^ V.AbstractionId.to_string abs_id0
+                        ^ AbstractionId.to_string abs_id0
                         ^ ":\n\n" ^ eval_ctx_to_string !ctx));
 
                     (* Update the environment - pay attention to the order: we
@@ -269,8 +262,8 @@ let collapse_ctx (loop_id : V.LoopId.id)
                     ctx := nctx;
 
                     (* Update the union find *)
-                    let abs_ref_merged = UF.union abs_ref0 abs_ref1 in
-                    UF.set abs_ref_merged abs_id))
+                    let abs_ref_merged = UnionFind.union abs_ref0 abs_ref1 in
+                    UnionFind.set abs_ref_merged abs_id))
                 abs_ids1)
         bids)
     abs_ids;
@@ -292,8 +285,8 @@ let collapse_ctx (loop_id : V.LoopId.id)
   (* Return the new context *)
   ctx
 
-let mk_collapse_ctx_merge_duplicate_funs (loop_id : V.LoopId.id)
-    (ctx : C.eval_ctx) : merge_duplicates_funcs =
+let mk_collapse_ctx_merge_duplicate_funs (loop_id : LoopId.id) (ctx : eval_ctx)
+    : merge_duplicates_funcs =
   (* Rem.: the merge functions raise exceptions (that we catch). *)
   let module S : MatchJoinState = struct
     let ctx = ctx
@@ -314,8 +307,8 @@ let mk_collapse_ctx_merge_duplicate_funs (loop_id : V.LoopId.id)
   *)
   let merge_amut_borrows id ty0 child0 _ty1 child1 =
     (* Sanity checks *)
-    assert (is_aignored child0.V.value);
-    assert (is_aignored child1.V.value);
+    assert (is_aignored child0.value);
+    assert (is_aignored child1.value);
 
     (* We need to pick a type for the avalue. The types on the left and on the
        right may use different regions: it doesn't really matter (here, we pick
@@ -324,8 +317,8 @@ let mk_collapse_ctx_merge_duplicate_funs (loop_id : V.LoopId.id)
     *)
     let ty = ty0 in
     let child = child0 in
-    let value = V.ABorrow (V.AMutBorrow (id, child)) in
-    { V.value; ty }
+    let value = ABorrow (AMutBorrow (id, child)) in
+    { value; ty }
   in
 
   let merge_ashared_borrows id ty0 ty1 =
@@ -339,37 +332,37 @@ let mk_collapse_ctx_merge_duplicate_funs (loop_id : V.LoopId.id)
 
     (* Same remarks as for [merge_amut_borrows] *)
     let ty = ty0 in
-    let value = V.ABorrow (V.ASharedBorrow id) in
-    { V.value; ty }
+    let value = ABorrow (ASharedBorrow id) in
+    { value; ty }
   in
 
   let merge_amut_loans id ty0 child0 _ty1 child1 =
     (* Sanity checks *)
-    assert (is_aignored child0.V.value);
-    assert (is_aignored child1.V.value);
+    assert (is_aignored child0.value);
+    assert (is_aignored child1.value);
     (* Same remarks as for [merge_amut_borrows] *)
     let ty = ty0 in
     let child = child0 in
-    let value = V.ALoan (V.AMutLoan (id, child)) in
-    { V.value; ty }
+    let value = ALoan (AMutLoan (id, child)) in
+    { value; ty }
   in
-  let merge_ashared_loans ids ty0 (sv0 : V.typed_value) child0 _ty1
-      (sv1 : V.typed_value) child1 =
+  let merge_ashared_loans ids ty0 (sv0 : typed_value) child0 _ty1
+      (sv1 : typed_value) child1 =
     (* Sanity checks *)
-    assert (is_aignored child0.V.value);
-    assert (is_aignored child1.V.value);
+    assert (is_aignored child0.value);
+    assert (is_aignored child1.value);
     (* Same remarks as for [merge_amut_borrows].
 
        This time we need to also merge the shared values. We rely on the
        join matcher [JM] to do so.
     *)
-    assert (not (value_has_loans_or_borrows ctx sv0.V.value));
-    assert (not (value_has_loans_or_borrows ctx sv1.V.value));
+    assert (not (value_has_loans_or_borrows ctx sv0.value));
+    assert (not (value_has_loans_or_borrows ctx sv1.value));
     let ty = ty0 in
     let child = child0 in
     let sv = M.match_typed_values ctx sv0 sv1 in
-    let value = V.ALoan (V.ASharedLoan (ids, sv, child)) in
-    { V.value; ty }
+    let value = ALoan (ASharedLoan (ids, sv, child)) in
+    { value; ty }
   in
   {
     merge_amut_borrows;
@@ -378,9 +371,9 @@ let mk_collapse_ctx_merge_duplicate_funs (loop_id : V.LoopId.id)
     merge_ashared_loans;
   }
 
-let merge_into_abstraction (loop_id : V.LoopId.id) (abs_kind : V.abs_kind)
-    (can_end : bool) (ctx : C.eval_ctx) (aid0 : V.AbstractionId.id)
-    (aid1 : V.AbstractionId.id) : C.eval_ctx * V.AbstractionId.id =
+let merge_into_abstraction (loop_id : LoopId.id) (abs_kind : abs_kind)
+    (can_end : bool) (ctx : eval_ctx) (aid0 : AbstractionId.id)
+    (aid1 : AbstractionId.id) : eval_ctx * AbstractionId.id =
   let merge_funs = mk_collapse_ctx_merge_duplicate_funs loop_id ctx in
   merge_into_abstraction abs_kind can_end (Some merge_funs) ctx aid0 aid1
 
@@ -391,14 +384,14 @@ let merge_into_abstraction (loop_id : V.LoopId.id) (abs_kind : V.abs_kind)
     We do this because when we join environments, we may introduce duplicated
     loans and borrows. See the explanations for {!join_ctxs}.
  *)
-let collapse_ctx_with_merge (loop_id : V.LoopId.id) (old_ids : ids_sets)
-    (ctx : C.eval_ctx) : C.eval_ctx =
+let collapse_ctx_with_merge (loop_id : LoopId.id) (old_ids : ids_sets)
+    (ctx : eval_ctx) : eval_ctx =
   let merge_funs = mk_collapse_ctx_merge_duplicate_funs loop_id ctx in
   try collapse_ctx loop_id (Some merge_funs) old_ids ctx
   with ValueMatchFailure _ -> raise (Failure "Unexpected")
 
-let join_ctxs (loop_id : V.LoopId.id) (fixed_ids : ids_sets) (ctx0 : C.eval_ctx)
-    (ctx1 : C.eval_ctx) : ctx_or_update =
+let join_ctxs (loop_id : LoopId.id) (fixed_ids : ids_sets) (ctx0 : eval_ctx)
+    (ctx1 : eval_ctx) : ctx_or_update =
   (* Debug *)
   log#ldebug
     (lazy
@@ -422,7 +415,7 @@ let join_ctxs (loop_id : V.LoopId.id) (fixed_ids : ids_sets) (ctx0 : C.eval_ctx)
   let nabs = ref [] in
 
   (* Explore the environments. *)
-  let join_suffixes (env0 : C.env) (env1 : C.env) : C.env =
+  let join_suffixes (env0 : env) (env1 : env) : env =
     (* Debug *)
     log#ldebug
       (lazy
@@ -434,16 +427,16 @@ let join_ctxs (loop_id : V.LoopId.id) (fixed_ids : ids_sets) (ctx0 : C.eval_ctx)
         ^ "\n\n"));
 
     (* Sanity check: there are no values/abstractions which should be in the prefix *)
-    let check_valid (ee : C.env_elem) : unit =
+    let check_valid (ee : env_elem) : unit =
       match ee with
-      | C.Var (C.VarBinder _, _) ->
+      | EBinding (BVar _, _) ->
           (* Variables are necessarily in the prefix *)
           raise (Failure "Unreachable")
-      | Var (C.DummyBinder did, _) ->
-          assert (not (C.DummyVarId.Set.mem did fixed_ids.dids))
-      | Abs abs ->
-          assert (not (V.AbstractionId.Set.mem abs.abs_id fixed_ids.aids))
-      | Frame ->
+      | EBinding (BDummy did, _) ->
+          assert (not (DummyVarId.Set.mem did fixed_ids.dids))
+      | EAbs abs ->
+          assert (not (AbstractionId.Set.mem abs.abs_id fixed_ids.aids))
+      | EFrame ->
           (* This should have been eliminated *)
           raise (Failure "Unreachable")
     in
@@ -451,7 +444,7 @@ let join_ctxs (loop_id : V.LoopId.id) (fixed_ids : ids_sets) (ctx0 : C.eval_ctx)
     List.iter check_valid env1;
     (* Concatenate the suffixes and append the abstractions introduced while
        joining the prefixes *)
-    let absl = List.map (fun abs -> C.Abs abs) (List.rev !nabs) in
+    let absl = List.map (fun abs -> EAbs abs) (List.rev !nabs) in
     List.concat [ env0; env1; absl ]
   in
 
@@ -464,14 +457,14 @@ let join_ctxs (loop_id : V.LoopId.id) (fixed_ids : ids_sets) (ctx0 : C.eval_ctx)
   let module JM = MakeJoinMatcher (S) in
   let module M = MakeMatcher (JM) in
   (* Rem.: this function raises exceptions *)
-  let rec join_prefixes (env0 : C.env) (env1 : C.env) : C.env =
+  let rec join_prefixes (env0 : env) (env1 : env) : env =
     match (env0, env1) with
-    | ( (C.Var (C.DummyBinder b0, v0) as var0) :: env0',
-        (C.Var (C.DummyBinder b1, v1) as var1) :: env1' ) ->
+    | ( (EBinding (BDummy b0, v0) as var0) :: env0',
+        (EBinding (BDummy b1, v1) as var1) :: env1' ) ->
         (* Debug *)
         log#ldebug
           (lazy
-            ("join_prefixes: DummyBinders:\n\n- fixed_ids:\n" ^ "\n"
+            ("join_prefixes: BDummys:\n\n- fixed_ids:\n" ^ "\n"
            ^ show_ids_sets fixed_ids ^ "\n\n- value0:\n"
             ^ env_elem_to_string ctx var0
             ^ "\n\n- value1:\n"
@@ -481,22 +474,22 @@ let join_ctxs (loop_id : V.LoopId.id) (fixed_ids : ids_sets) (ctx0 : C.eval_ctx)
         (* Two cases: the dummy value is an old value, in which case the bindings
            must be the same and we must join their values. Otherwise, it means we
            are not in the prefix anymore *)
-        if C.DummyVarId.Set.mem b0 fixed_ids.dids then (
+        if DummyVarId.Set.mem b0 fixed_ids.dids then (
           (* Still in the prefix: match the values *)
           assert (b0 = b1);
           let b = b0 in
           let v = M.match_typed_values ctx v0 v1 in
-          let var = C.Var (C.DummyBinder b, v) in
+          let var = EBinding (BDummy b, v) in
           (* Continue *)
           var :: join_prefixes env0' env1')
         else (* Not in the prefix anymore *)
           join_suffixes env0 env1
-    | ( (C.Var (C.VarBinder b0, v0) as var0) :: env0',
-        (C.Var (C.VarBinder b1, v1) as var1) :: env1' ) ->
+    | ( (EBinding (BVar b0, v0) as var0) :: env0',
+        (EBinding (BVar b1, v1) as var1) :: env1' ) ->
         (* Debug *)
         log#ldebug
           (lazy
-            ("join_prefixes: VarBinders:\n\n- fixed_ids:\n" ^ "\n"
+            ("join_prefixes: BVars:\n\n- fixed_ids:\n" ^ "\n"
            ^ show_ids_sets fixed_ids ^ "\n\n- value0:\n"
             ^ env_elem_to_string ctx var0
             ^ "\n\n- value1:\n"
@@ -509,10 +502,10 @@ let join_ctxs (loop_id : V.LoopId.id) (fixed_ids : ids_sets) (ctx0 : C.eval_ctx)
         (* Match the values *)
         let b = b0 in
         let v = M.match_typed_values ctx v0 v1 in
-        let var = C.Var (C.VarBinder b, v) in
+        let var = EBinding (BVar b, v) in
         (* Continue *)
         var :: join_prefixes env0' env1'
-    | (C.Abs abs0 as abs) :: env0', C.Abs abs1 :: env1' ->
+    | (EAbs abs0 as abs) :: env0', EAbs abs1 :: env1' ->
         (* Debug *)
         log#ldebug
           (lazy
@@ -521,7 +514,7 @@ let join_ctxs (loop_id : V.LoopId.id) (fixed_ids : ids_sets) (ctx0 : C.eval_ctx)
            ^ "\n\n- abs1:\n" ^ abs_to_string ctx abs1 ^ "\n\n"));
 
         (* Same as for the dummy values: there are two cases *)
-        if V.AbstractionId.Set.mem abs0.abs_id fixed_ids.aids then (
+        if AbstractionId.Set.mem abs0.abs_id fixed_ids.aids then (
           (* Still in the prefix: the abstractions must be the same *)
           assert (abs0 = abs1);
           (* Continue *)
@@ -537,21 +530,20 @@ let join_ctxs (loop_id : V.LoopId.id) (fixed_ids : ids_sets) (ctx0 : C.eval_ctx)
     (* Remove the frame delimiter (the first element of an environment is a frame delimiter) *)
     let env0, env1 =
       match (env0, env1) with
-      | C.Frame :: env0, C.Frame :: env1 -> (env0, env1)
+      | EFrame :: env0, EFrame :: env1 -> (env0, env1)
       | _ -> raise (Failure "Unreachable")
     in
 
     log#ldebug
       (lazy
-        ("- env0:\n" ^ C.show_env env0 ^ "\n\n- env1:\n" ^ C.show_env env1
-       ^ "\n\n"));
+        ("- env0:\n" ^ show_env env0 ^ "\n\n- env1:\n" ^ show_env env1 ^ "\n\n"));
 
-    let env = List.rev (C.Frame :: join_prefixes env0 env1) in
+    let env = List.rev (EFrame :: join_prefixes env0 env1) in
 
     (* Construct the joined context - of course, the type, fun, etc. contexts
      * should be the same in the two contexts *)
     let {
-      C.type_context;
+      type_context;
       fun_context;
       global_context;
       trait_decls_context;
@@ -560,16 +552,14 @@ let join_ctxs (loop_id : V.LoopId.id) (fixed_ids : ids_sets) (ctx0 : C.eval_ctx)
       type_vars;
       const_generic_vars;
       const_generic_vars_map;
-      norm_trait_etypes;
-      norm_trait_rtypes;
-      norm_trait_stypes;
+      norm_trait_types;
       env = _;
       ended_regions = ended_regions0;
     } =
       ctx0
     in
     let {
-      C.type_context = _;
+      type_context = _;
       fun_context = _;
       global_context = _;
       trait_decls_context = _;
@@ -578,18 +568,16 @@ let join_ctxs (loop_id : V.LoopId.id) (fixed_ids : ids_sets) (ctx0 : C.eval_ctx)
       type_vars = _;
       const_generic_vars = _;
       const_generic_vars_map = _;
-      norm_trait_etypes = _;
-      norm_trait_rtypes = _;
-      norm_trait_stypes = _;
+      norm_trait_types = _;
       env = _;
       ended_regions = ended_regions1;
     } =
       ctx1
     in
-    let ended_regions = T.RegionId.Set.union ended_regions0 ended_regions1 in
+    let ended_regions = RegionId.Set.union ended_regions0 ended_regions1 in
     Ok
       {
-        C.type_context;
+        type_context;
         fun_context;
         global_context;
         trait_decls_context;
@@ -598,25 +586,23 @@ let join_ctxs (loop_id : V.LoopId.id) (fixed_ids : ids_sets) (ctx0 : C.eval_ctx)
         type_vars;
         const_generic_vars;
         const_generic_vars_map;
-        norm_trait_etypes;
-        norm_trait_rtypes;
-        norm_trait_stypes;
+        norm_trait_types;
         env;
         ended_regions;
       }
   with ValueMatchFailure e -> Error e
 
 (** Destructure all the new abstractions *)
-let destructure_new_abs (loop_id : V.LoopId.id)
-    (old_abs_ids : V.AbstractionId.Set.t) (ctx : C.eval_ctx) : C.eval_ctx =
-  let abs_kind = V.Loop (loop_id, None, V.LoopSynthInput) in
+let destructure_new_abs (loop_id : LoopId.id)
+    (old_abs_ids : AbstractionId.Set.t) (ctx : eval_ctx) : eval_ctx =
+  let abs_kind : abs_kind = Loop (loop_id, None, LoopSynthInput) in
   let can_end = true in
   let destructure_shared_values = true in
-  let is_fresh_abs_id (id : V.AbstractionId.id) : bool =
-    not (V.AbstractionId.Set.mem id old_abs_ids)
+  let is_fresh_abs_id (id : AbstractionId.id) : bool =
+    not (AbstractionId.Set.mem id old_abs_ids)
   in
   let env =
-    C.env_map_abs
+    env_map_abs
       (fun abs ->
         if is_fresh_abs_id abs.abs_id then
           let abs =
@@ -634,24 +620,22 @@ let destructure_new_abs (loop_id : V.LoopId.id)
     abstractions in contexts which are later joined: we have to make sure two
     contexts we join don't have non-fixed abstractions with the same ids.
   *)
-let refresh_abs (old_abs : V.AbstractionId.Set.t) (ctx : C.eval_ctx) :
-    C.eval_ctx =
+let refresh_abs (old_abs : AbstractionId.Set.t) (ctx : eval_ctx) : eval_ctx =
   let ids, _ = compute_context_ids ctx in
-  let abs_to_refresh = V.AbstractionId.Set.diff ids.aids old_abs in
+  let abs_to_refresh = AbstractionId.Set.diff ids.aids old_abs in
   let aids_subst =
     List.map
-      (fun id -> (id, C.fresh_abstraction_id ()))
-      (V.AbstractionId.Set.elements abs_to_refresh)
+      (fun id -> (id, fresh_abstraction_id ()))
+      (AbstractionId.Set.elements abs_to_refresh)
   in
-  let aids_subst = V.AbstractionId.Map.of_list aids_subst in
+  let aids_subst = AbstractionId.Map.of_list aids_subst in
   let subst id =
-    match V.AbstractionId.Map.find_opt id aids_subst with
+    match AbstractionId.Map.find_opt id aids_subst with
     | None -> id
     | Some id -> id
   in
   let env =
-    Subst.env_subst_ids
-      (fun x -> x)
+    Substitute.env_subst_ids
       (fun x -> x)
       (fun x -> x)
       (fun x -> x)
@@ -659,11 +643,11 @@ let refresh_abs (old_abs : V.AbstractionId.Set.t) (ctx : C.eval_ctx) :
       (fun x -> x)
       subst ctx.env
   in
-  { ctx with C.env }
+  { ctx with env }
 
-let loop_join_origin_with_continue_ctxs (config : C.config)
-    (loop_id : V.LoopId.id) (fixed_ids : ids_sets) (old_ctx : C.eval_ctx)
-    (ctxl : C.eval_ctx list) : (C.eval_ctx * C.eval_ctx list) * C.eval_ctx =
+let loop_join_origin_with_continue_ctxs (config : config) (loop_id : LoopId.id)
+    (fixed_ids : ids_sets) (old_ctx : eval_ctx) (ctxl : eval_ctx list) :
+    (eval_ctx * eval_ctx list) * eval_ctx =
   (* # Join with the new contexts, one by one
 
      For every context, we repeteadly attempt to join it with the current
@@ -673,7 +657,7 @@ let loop_join_origin_with_continue_ctxs (config : C.config)
      in the one we are trying to add to the join.
   *)
   let joined_ctx = ref old_ctx in
-  let rec join_one_aux (ctx : C.eval_ctx) : C.eval_ctx =
+  let rec join_one_aux (ctx : eval_ctx) : eval_ctx =
     match join_ctxs loop_id fixed_ids !joined_ctx ctx with
     | Ok nctx ->
         joined_ctx := nctx;
@@ -690,7 +674,7 @@ let loop_join_origin_with_continue_ctxs (config : C.config)
         in
         join_one_aux ctx
   in
-  let join_one (ctx : C.eval_ctx) : C.eval_ctx =
+  let join_one (ctx : eval_ctx) : eval_ctx =
     log#ldebug
       (lazy
         ("loop_join_origin_with_continue_ctxs:join_one: initial ctx:\n"
diff --git a/compiler/InterpreterLoopsJoinCtxs.mli b/compiler/InterpreterLoopsJoinCtxs.mli
index ae655fb8..bb9f14ed 100644
--- a/compiler/InterpreterLoopsJoinCtxs.mli
+++ b/compiler/InterpreterLoopsJoinCtxs.mli
@@ -1,13 +1,5 @@
-module T = Types
-module PV = PrimitiveValues
-module V = Values
-module E = Expressions
-module C = Contexts
-module Subst = Substitute
-module A = LlbcAst
-module L = Logging
-module Inv = Invariants
-module S = SynthesizeSymbolic
+open Values
+open Contexts
 open InterpreterUtils
 open InterpreterLoopsCore
 
@@ -24,13 +16,13 @@ open InterpreterLoopsCore
     - [aid1]
  *)
 val merge_into_abstraction :
-  V.loop_id ->
-  V.abs_kind ->
+  loop_id ->
+  abs_kind ->
   bool ->
-  C.eval_ctx ->
-  V.abstraction_id ->
-  V.abstraction_id ->
-  C.eval_ctx * V.abstraction_id
+  eval_ctx ->
+  abstraction_id ->
+  abstraction_id ->
+  eval_ctx * abstraction_id
 
 (** Join two contexts.
 
@@ -92,8 +84,7 @@ val merge_into_abstraction :
     - [ctx0]
     - [ctx1]
   *)
-val join_ctxs :
-  V.loop_id -> ids_sets -> C.eval_ctx -> C.eval_ctx -> ctx_or_update
+val join_ctxs : loop_id -> ids_sets -> eval_ctx -> eval_ctx -> ctx_or_update
 
 (** Join the context at the entry of the loop with the contexts upon reentry
     (upon reaching the [Continue] statement - the goal is to compute a fixed
@@ -112,9 +103,9 @@ val join_ctxs :
     - [ctxl]
  *)
 val loop_join_origin_with_continue_ctxs :
-  C.config ->
-  V.loop_id ->
+  config ->
+  loop_id ->
   ids_sets ->
-  C.eval_ctx ->
-  C.eval_ctx list ->
-  (C.eval_ctx * C.eval_ctx list) * C.eval_ctx
+  eval_ctx ->
+  eval_ctx list ->
+  (eval_ctx * eval_ctx list) * eval_ctx
diff --git a/compiler/InterpreterLoopsMatchCtxs.ml b/compiler/InterpreterLoopsMatchCtxs.ml
index 8cab546e..74f9ba2c 100644
--- a/compiler/InterpreterLoopsMatchCtxs.ml
+++ b/compiler/InterpreterLoopsMatchCtxs.ml
@@ -4,35 +4,29 @@
     to check if two contexts are equivalent (modulo conversion).
  *)
 
-module T = Types
-module PV = PrimitiveValues
-module V = Values
-module E = Expressions
-module C = Contexts
-module Subst = Substitute
-module A = LlbcAst
-module L = Logging
+open Types
+open Values
+open Contexts
 open TypesUtils
 open ValuesUtils
-module Inv = Invariants
-module S = SynthesizeSymbolic
 open Cps
 open InterpreterUtils
 open InterpreterBorrows
 open InterpreterLoopsCore
+module S = SynthesizeSymbolic
 
 (** The local logger *)
-let log = L.loops_match_ctxs_log
+let log = Logging.loops_match_ctxs_log
 
 let compute_abs_borrows_loans_maps (no_duplicates : bool)
-    (explore : V.abs -> bool) (env : C.env) : abs_borrows_loans_maps =
+    (explore : abs -> bool) (env : env) : abs_borrows_loans_maps =
   let abs_ids = ref [] in
-  let abs_to_borrows = ref V.AbstractionId.Map.empty in
-  let abs_to_loans = ref V.AbstractionId.Map.empty in
-  let abs_to_borrows_loans = ref V.AbstractionId.Map.empty in
-  let borrow_to_abs = ref V.BorrowId.Map.empty in
-  let loan_to_abs = ref V.BorrowId.Map.empty in
-  let borrow_loan_to_abs = ref V.BorrowId.Map.empty in
+  let abs_to_borrows = ref AbstractionId.Map.empty in
+  let abs_to_loans = ref AbstractionId.Map.empty in
+  let abs_to_borrows_loans = ref AbstractionId.Map.empty in
+  let borrow_to_abs = ref BorrowId.Map.empty in
+  let loan_to_abs = ref BorrowId.Map.empty in
+  let borrow_loan_to_abs = ref BorrowId.Map.empty in
 
   let module R (Id0 : Identifiers.Id) (Id1 : Identifiers.Id) = struct
     (*
@@ -65,8 +59,8 @@ let compute_abs_borrows_loans_maps (no_duplicates : bool)
                 Some (Id1.Set.add id1 ids))
           !map
   end in
-  let module RAbsBorrow = R (V.AbstractionId) (V.BorrowId) in
-  let module RBorrowAbs = R (V.BorrowId) (V.AbstractionId) in
+  let module RAbsBorrow = R (AbstractionId) (BorrowId) in
+  let module RBorrowAbs = R (BorrowId) (AbstractionId) in
   let register_borrow_id abs_id bid =
     RAbsBorrow.register_mapping false no_duplicates abs_to_borrows abs_id bid;
     RAbsBorrow.register_mapping false false abs_to_borrows_loans abs_id bid;
@@ -85,7 +79,7 @@ let compute_abs_borrows_loans_maps (no_duplicates : bool)
 
   let explore_abs =
     object (self : 'self)
-      inherit [_] V.iter_typed_avalue as super
+      inherit [_] iter_typed_avalue as super
 
       (** Make sure we don't register the ignored ids *)
       method! visit_aloan_content abs_id lc =
@@ -119,14 +113,14 @@ let compute_abs_borrows_loans_maps (no_duplicates : bool)
     end
   in
 
-  C.env_iter_abs
+  env_iter_abs
     (fun abs ->
       let abs_id = abs.abs_id in
       if explore abs then (
         abs_to_borrows :=
-          V.AbstractionId.Map.add abs_id V.BorrowId.Set.empty !abs_to_borrows;
+          AbstractionId.Map.add abs_id BorrowId.Set.empty !abs_to_borrows;
         abs_to_loans :=
-          V.AbstractionId.Map.add abs_id V.BorrowId.Set.empty !abs_to_loans;
+          AbstractionId.Map.add abs_id BorrowId.Set.empty !abs_to_loans;
         abs_ids := abs.abs_id :: !abs_ids;
         List.iter (explore_abs#visit_typed_avalue abs.abs_id) abs.avalues)
       else ())
@@ -144,12 +138,15 @@ let compute_abs_borrows_loans_maps (no_duplicates : bool)
     borrow_loan_to_abs = !borrow_loan_to_abs;
   }
 
-(** Match two types during a join. *)
-let rec match_types (match_distinct_types : 'r T.ty -> 'r T.ty -> 'r T.ty)
-    (match_regions : 'r -> 'r -> 'r) (ty0 : 'r T.ty) (ty1 : 'r T.ty) : 'r T.ty =
+(** Match two types during a join.
+
+    TODO: probably don't need to take [match_regions] as input anymore.
+ *)
+let rec match_types (match_distinct_types : ty -> ty -> ty)
+    (match_regions : region -> region -> region) (ty0 : ty) (ty1 : ty) : ty =
   let match_rec = match_types match_distinct_types match_regions in
   match (ty0, ty1) with
-  | Adt (id0, generics0), Adt (id1, generics1) ->
+  | TAdt (id0, generics0), TAdt (id1, generics1) ->
       assert (id0 = id1);
       assert (generics0.const_generics = generics1.const_generics);
       assert (generics0.trait_refs = generics1.trait_refs);
@@ -166,108 +163,108 @@ let rec match_types (match_distinct_types : 'r T.ty -> 'r T.ty -> 'r T.ty)
           (fun (ty0, ty1) -> match_rec ty0 ty1)
           (List.combine generics0.types generics1.types)
       in
-      let generics = { T.regions; types; const_generics; trait_refs } in
-      Adt (id, generics)
-  | TypeVar vid0, TypeVar vid1 ->
+      let generics = { regions; types; const_generics; trait_refs } in
+      TAdt (id, generics)
+  | TVar vid0, TVar vid1 ->
       assert (vid0 = vid1);
       let vid = vid0 in
-      TypeVar vid
-  | Literal lty0, Literal lty1 ->
+      TVar vid
+  | TLiteral lty0, TLiteral lty1 ->
       assert (lty0 = lty1);
       ty0
-  | Never, Never -> ty0
-  | Ref (r0, ty0, k0), Ref (r1, ty1, k1) ->
+  | TNever, TNever -> ty0
+  | TRef (r0, ty0, k0), TRef (r1, ty1, k1) ->
       let r = match_regions r0 r1 in
       let ty = match_rec ty0 ty1 in
       assert (k0 = k1);
       let k = k0 in
-      Ref (r, ty, k)
+      TRef (r, ty, k)
   | _ -> match_distinct_types ty0 ty1
 
 module MakeMatcher (M : PrimMatcher) : Matcher = struct
-  let rec match_typed_values (ctx : C.eval_ctx) (v0 : V.typed_value)
-      (v1 : V.typed_value) : V.typed_value =
+  let rec match_typed_values (ctx : eval_ctx) (v0 : typed_value)
+      (v1 : typed_value) : typed_value =
     let match_rec = match_typed_values ctx in
-    let ty = M.match_etys v0.V.ty v1.V.ty in
-    match (v0.V.value, v1.V.value) with
-    | V.Literal lv0, V.Literal lv1 ->
+    let ty = M.match_etys v0.ty v1.ty in
+    match (v0.value, v1.value) with
+    | VLiteral lv0, VLiteral lv1 ->
         if lv0 = lv1 then v1 else M.match_distinct_literals ty lv0 lv1
-    | V.Adt av0, V.Adt av1 ->
+    | VAdt av0, VAdt av1 ->
         if av0.variant_id = av1.variant_id then
           let fields = List.combine av0.field_values av1.field_values in
           let field_values =
             List.map (fun (f0, f1) -> match_rec f0 f1) fields
           in
-          let value : V.value =
-            V.Adt { variant_id = av0.variant_id; field_values }
+          let value : value =
+            VAdt { variant_id = av0.variant_id; field_values }
           in
-          { V.value; ty = v1.V.ty }
+          { value; ty = v1.ty }
         else (
           (* For now, we don't merge ADTs which contain borrows *)
-          assert (not (value_has_borrows ctx v0.V.value));
-          assert (not (value_has_borrows ctx v1.V.value));
+          assert (not (value_has_borrows ctx v0.value));
+          assert (not (value_has_borrows ctx v1.value));
           (* Merge *)
           M.match_distinct_adts ty av0 av1)
-    | Bottom, Bottom -> v0
-    | Borrow bc0, Borrow bc1 ->
+    | VBottom, VBottom -> v0
+    | VBorrow bc0, VBorrow bc1 ->
         let bc =
           match (bc0, bc1) with
-          | SharedBorrow bid0, SharedBorrow bid1 ->
+          | VSharedBorrow bid0, VSharedBorrow bid1 ->
               let bid = M.match_shared_borrows match_rec ty bid0 bid1 in
-              V.SharedBorrow bid
-          | MutBorrow (bid0, bv0), MutBorrow (bid1, bv1) ->
+              VSharedBorrow bid
+          | VMutBorrow (bid0, bv0), VMutBorrow (bid1, bv1) ->
               let bv = match_rec bv0 bv1 in
-              assert (not (value_has_borrows ctx bv.V.value));
+              assert (not (value_has_borrows ctx bv.value));
               let bid, bv = M.match_mut_borrows ty bid0 bv0 bid1 bv1 bv in
-              V.MutBorrow (bid, bv)
-          | ReservedMutBorrow _, _
-          | _, ReservedMutBorrow _
-          | SharedBorrow _, MutBorrow _
-          | MutBorrow _, SharedBorrow _ ->
+              VMutBorrow (bid, bv)
+          | VReservedMutBorrow _, _
+          | _, VReservedMutBorrow _
+          | VSharedBorrow _, VMutBorrow _
+          | VMutBorrow _, VSharedBorrow _ ->
               (* If we get here, either there is a typing inconsistency, or we are
                  trying to match a reserved borrow, which shouldn't happen because
                  reserved borrow should be eliminated very quickly - they are introduced
                  just before function calls which activate them *)
               raise (Failure "Unexpected")
         in
-        { V.value = V.Borrow bc; ty }
-    | Loan lc0, Loan lc1 ->
+        { value = VBorrow bc; ty }
+    | VLoan lc0, VLoan lc1 ->
         (* TODO: maybe we should enforce that the ids are always exactly the same -
            without matching *)
         let lc =
           match (lc0, lc1) with
-          | SharedLoan (ids0, sv0), SharedLoan (ids1, sv1) ->
+          | VSharedLoan (ids0, sv0), VSharedLoan (ids1, sv1) ->
               let sv = match_rec sv0 sv1 in
-              assert (not (value_has_borrows ctx sv.V.value));
+              assert (not (value_has_borrows ctx sv.value));
               let ids, sv = M.match_shared_loans ty ids0 ids1 sv in
-              V.SharedLoan (ids, sv)
-          | MutLoan id0, MutLoan id1 ->
+              VSharedLoan (ids, sv)
+          | VMutLoan id0, VMutLoan id1 ->
               let id = M.match_mut_loans ty id0 id1 in
-              V.MutLoan id
-          | SharedLoan _, MutLoan _ | MutLoan _, SharedLoan _ ->
+              VMutLoan id
+          | VSharedLoan _, VMutLoan _ | VMutLoan _, VSharedLoan _ ->
               raise (Failure "Unreachable")
         in
-        { V.value = Loan lc; ty = v1.V.ty }
-    | Symbolic sv0, Symbolic sv1 ->
+        { value = VLoan lc; ty = v1.ty }
+    | VSymbolic sv0, VSymbolic sv1 ->
         (* For now, we force all the symbolic values containing borrows to
            be eagerly expanded, and we don't support nested borrows *)
-        assert (not (value_has_borrows ctx v0.V.value));
-        assert (not (value_has_borrows ctx v1.V.value));
+        assert (not (value_has_borrows ctx v0.value));
+        assert (not (value_has_borrows ctx v1.value));
         (* Match *)
         let sv = M.match_symbolic_values sv0 sv1 in
-        { v1 with V.value = V.Symbolic sv }
-    | Loan lc, _ -> (
+        { v1 with value = VSymbolic sv }
+    | VLoan lc, _ -> (
         match lc with
-        | SharedLoan (ids, _) -> raise (ValueMatchFailure (LoansInLeft ids))
-        | MutLoan id -> raise (ValueMatchFailure (LoanInLeft id)))
-    | _, Loan lc -> (
+        | VSharedLoan (ids, _) -> raise (ValueMatchFailure (LoansInLeft ids))
+        | VMutLoan id -> raise (ValueMatchFailure (LoanInLeft id)))
+    | _, VLoan lc -> (
         match lc with
-        | SharedLoan (ids, _) -> raise (ValueMatchFailure (LoansInRight ids))
-        | MutLoan id -> raise (ValueMatchFailure (LoanInRight id)))
-    | Symbolic sv, _ -> M.match_symbolic_with_other true sv v1
-    | _, Symbolic sv -> M.match_symbolic_with_other false sv v0
-    | Bottom, _ -> M.match_bottom_with_other true v1
-    | _, Bottom -> M.match_bottom_with_other false v0
+        | VSharedLoan (ids, _) -> raise (ValueMatchFailure (LoansInRight ids))
+        | VMutLoan id -> raise (ValueMatchFailure (LoanInRight id)))
+    | VSymbolic sv, _ -> M.match_symbolic_with_other true sv v1
+    | _, VSymbolic sv -> M.match_symbolic_with_other false sv v0
+    | VBottom, _ -> M.match_bottom_with_other true v1
+    | _, VBottom -> M.match_bottom_with_other false v0
     | _ ->
         log#ldebug
           (lazy
@@ -277,8 +274,8 @@ module MakeMatcher (M : PrimMatcher) : Matcher = struct
             ^ typed_value_to_string ctx v1));
         raise (Failure "Unexpected match case")
 
-  and match_typed_avalues (ctx : C.eval_ctx) (v0 : V.typed_avalue)
-      (v1 : V.typed_avalue) : V.typed_avalue =
+  and match_typed_avalues (ctx : eval_ctx) (v0 : typed_avalue)
+      (v1 : typed_avalue) : typed_avalue =
     log#ldebug
       (lazy
         ("match_typed_avalues:\n- value0: "
@@ -288,20 +285,20 @@ module MakeMatcher (M : PrimMatcher) : Matcher = struct
 
     let match_rec = match_typed_values ctx in
     let match_arec = match_typed_avalues ctx in
-    let ty = M.match_rtys v0.V.ty v1.V.ty in
-    match (v0.V.value, v1.V.value) with
-    | V.AAdt av0, V.AAdt av1 ->
+    let ty = M.match_rtys v0.ty v1.ty in
+    match (v0.value, v1.value) with
+    | AAdt av0, AAdt av1 ->
         if av0.variant_id = av1.variant_id then
           let fields = List.combine av0.field_values av1.field_values in
           let field_values =
             List.map (fun (f0, f1) -> match_arec f0 f1) fields
           in
-          let value : V.avalue =
-            V.AAdt { variant_id = av0.variant_id; field_values }
+          let value : avalue =
+            AAdt { variant_id = av0.variant_id; field_values }
           in
-          { V.value; ty }
+          { value; ty }
         else (* Merge *)
-          M.match_distinct_aadts v0.V.ty av0 v1.V.ty av1 ty
+          M.match_distinct_aadts v0.ty av0 v1.ty av1 ty
     | ABottom, ABottom -> mk_abottom ty
     | AIgnored, AIgnored -> mk_aignored ty
     | ABorrow bc0, ABorrow bc1 -> (
@@ -309,7 +306,7 @@ module MakeMatcher (M : PrimMatcher) : Matcher = struct
         match (bc0, bc1) with
         | ASharedBorrow bid0, ASharedBorrow bid1 ->
             log#ldebug (lazy "match_typed_avalues: shared borrows");
-            M.match_ashared_borrows v0.V.ty bid0 v1.V.ty bid1 ty
+            M.match_ashared_borrows v0.ty bid0 v1.ty bid1 ty
         | AMutBorrow (bid0, av0), AMutBorrow (bid1, av1) ->
             log#ldebug (lazy "match_typed_avalues: mut borrows");
             log#ldebug
@@ -318,7 +315,7 @@ module MakeMatcher (M : PrimMatcher) : Matcher = struct
             let av = match_arec av0 av1 in
             log#ldebug
               (lazy "match_typed_avalues: mut borrows: matched children values");
-            M.match_amut_borrows v0.V.ty bid0 av0 v1.V.ty bid1 av1 ty av
+            M.match_amut_borrows v0.ty bid0 av0 v1.ty bid1 av1 ty av
         | AIgnoredMutBorrow _, AIgnoredMutBorrow _ ->
             (* The abstractions are destructured: we shouldn't get there *)
             raise (Failure "Unexpected")
@@ -351,9 +348,8 @@ module MakeMatcher (M : PrimMatcher) : Matcher = struct
             log#ldebug (lazy "match_typed_avalues: shared loans");
             let sv = match_rec sv0 sv1 in
             let av = match_arec av0 av1 in
-            assert (not (value_has_borrows ctx sv.V.value));
-            M.match_ashared_loans v0.V.ty ids0 sv0 av0 v1.V.ty ids1 sv1 av1 ty
-              sv av
+            assert (not (value_has_borrows ctx sv.value));
+            M.match_ashared_loans v0.ty ids0 sv0 av0 v1.ty ids1 sv1 av1 ty sv av
         | AMutLoan (id0, av0), AMutLoan (id1, av1) ->
             log#ldebug (lazy "match_typed_avalues: mut loans");
             log#ldebug
@@ -361,7 +357,7 @@ module MakeMatcher (M : PrimMatcher) : Matcher = struct
             let av = match_arec av0 av1 in
             log#ldebug
               (lazy "match_typed_avalues: mut loans: matched children values");
-            M.match_amut_loans v0.V.ty id0 av0 v1.V.ty id1 av1 ty av
+            M.match_amut_loans v0.ty id0 av0 v1.ty id1 av1 ty av
         | AIgnoredMutLoan _, AIgnoredMutLoan _
         | AIgnoredSharedLoan _, AIgnoredSharedLoan _ ->
             (* Those should have been filtered when destructuring the abstractions -
@@ -377,9 +373,9 @@ end
 
 module MakeJoinMatcher (S : MatchJoinState) : PrimMatcher = struct
   (** Small utility *)
-  let push_abs (abs : V.abs) : unit = S.nabs := abs :: !S.nabs
+  let push_abs (abs : abs) : unit = S.nabs := abs :: !S.nabs
 
-  let push_absl (absl : V.abs list) : unit = List.iter push_abs absl
+  let push_absl (absl : abs list) : unit = List.iter push_abs absl
 
   let match_etys ty0 ty1 =
     assert (ty0 = ty1);
@@ -391,29 +387,29 @@ module MakeJoinMatcher (S : MatchJoinState) : PrimMatcher = struct
     assert (ty0 = ty1);
     ty0
 
-  let match_distinct_literals (ty : T.ety) (_ : V.literal) (_ : V.literal) :
-      V.typed_value =
-    mk_fresh_symbolic_typed_value_from_ety V.LoopJoin ty
+  let match_distinct_literals (ty : ety) (_ : literal) (_ : literal) :
+      typed_value =
+    mk_fresh_symbolic_typed_value_from_no_regions_ty LoopJoin ty
 
-  let match_distinct_adts (ty : T.ety) (adt0 : V.adt_value) (adt1 : V.adt_value)
-      : V.typed_value =
+  let match_distinct_adts (ty : ety) (adt0 : adt_value) (adt1 : adt_value) :
+      typed_value =
     (* Check that the ADTs don't contain borrows - this is redundant with checks
        performed by the caller, but we prefer to be safe with regards to future
        updates
     *)
-    let check_no_borrows (v : V.typed_value) =
-      assert (not (value_has_borrows S.ctx v.V.value))
+    let check_no_borrows (v : typed_value) =
+      assert (not (value_has_borrows S.ctx v.value))
     in
     List.iter check_no_borrows adt0.field_values;
     List.iter check_no_borrows adt1.field_values;
 
     (* Check if there are loans: we request to end them *)
-    let check_loans (left : bool) (fields : V.typed_value list) : unit =
+    let check_loans (left : bool) (fields : typed_value list) : unit =
       match InterpreterBorrowsCore.get_first_loan_in_values fields with
-      | Some (V.SharedLoan (ids, _)) ->
+      | Some (VSharedLoan (ids, _)) ->
           if left then raise (ValueMatchFailure (LoansInLeft ids))
           else raise (ValueMatchFailure (LoansInRight ids))
-      | Some (V.MutLoan id) ->
+      | Some (VMutLoan id) ->
           if left then raise (ValueMatchFailure (LoanInLeft id))
           else raise (ValueMatchFailure (LoanInRight id))
       | None -> ()
@@ -422,10 +418,10 @@ module MakeJoinMatcher (S : MatchJoinState) : PrimMatcher = struct
     check_loans false adt1.field_values;
 
     (* No borrows, no loans: we can introduce a symbolic value *)
-    mk_fresh_symbolic_typed_value_from_ety V.LoopJoin ty
+    mk_fresh_symbolic_typed_value_from_no_regions_ty LoopJoin ty
 
-  let match_shared_borrows _ (ty : T.ety) (bid0 : V.borrow_id)
-      (bid1 : V.borrow_id) : V.borrow_id =
+  let match_shared_borrows _ (ty : ety) (bid0 : borrow_id) (bid1 : borrow_id) :
+      borrow_id =
     if bid0 = bid1 then bid0
     else
       (* We replace bid0 and bid1 with a fresh borrow id, and introduce
@@ -434,45 +430,42 @@ module MakeJoinMatcher (S : MatchJoinState) : PrimMatcher = struct
            { SB bid0, SB bid1, SL {bid2} }
          ]}
       *)
-      let rid = C.fresh_region_id () in
-      let bid2 = C.fresh_borrow_id () in
+      let rid = fresh_region_id () in
+      let bid2 = fresh_borrow_id () in
 
       (* Generate a fresh symbolic value for the shared value *)
       let _, bv_ty, kind = ty_as_ref ty in
-      let sv = mk_fresh_symbolic_typed_value_from_ety V.LoopJoin bv_ty in
-
-      let borrow_ty =
-        mk_ref_ty (T.Var rid) (ety_no_regions_to_rty bv_ty) kind
+      let sv =
+        mk_fresh_symbolic_typed_value_from_no_regions_ty LoopJoin bv_ty
       in
 
+      let borrow_ty = mk_ref_ty (RVar rid) bv_ty kind in
+
       (* Generate the avalues for the abstraction *)
-      let mk_aborrow (bid : V.borrow_id) : V.typed_avalue =
-        let value = V.ABorrow (V.ASharedBorrow bid) in
-        { V.value; ty = borrow_ty }
+      let mk_aborrow (bid : borrow_id) : typed_avalue =
+        let value = ABorrow (ASharedBorrow bid) in
+        { value; ty = borrow_ty }
       in
       let borrows = [ mk_aborrow bid0; mk_aborrow bid1 ] in
 
       let loan =
-        V.ASharedLoan
-          ( V.BorrowId.Set.singleton bid2,
-            sv,
-            mk_aignored (ety_no_regions_to_rty bv_ty) )
+        ASharedLoan (BorrowId.Set.singleton bid2, sv, mk_aignored bv_ty)
       in
       (* Note that an aloan has a borrow type *)
-      let loan = { V.value = V.ALoan loan; ty = borrow_ty } in
+      let loan : typed_avalue = { value = ALoan loan; ty = borrow_ty } in
 
       let avalues = List.append borrows [ loan ] in
 
       (* Generate the abstraction *)
       let abs =
         {
-          V.abs_id = C.fresh_abstraction_id ();
-          kind = V.Loop (S.loop_id, None, LoopSynthInput);
+          abs_id = fresh_abstraction_id ();
+          kind = Loop (S.loop_id, None, LoopSynthInput);
           can_end = true;
-          parents = V.AbstractionId.Set.empty;
+          parents = AbstractionId.Set.empty;
           original_parents = [];
-          regions = T.RegionId.Set.singleton rid;
-          ancestors_regions = T.RegionId.Set.empty;
+          regions = RegionId.Set.singleton rid;
+          ancestors_regions = RegionId.Set.empty;
           avalues;
         }
       in
@@ -481,9 +474,9 @@ module MakeJoinMatcher (S : MatchJoinState) : PrimMatcher = struct
       (* Return the new borrow *)
       bid2
 
-  let match_mut_borrows (ty : T.ety) (bid0 : V.borrow_id) (bv0 : V.typed_value)
-      (bid1 : V.borrow_id) (bv1 : V.typed_value) (bv : V.typed_value) :
-      V.borrow_id * V.typed_value =
+  let match_mut_borrows (ty : ety) (bid0 : borrow_id) (bv0 : typed_value)
+      (bid1 : borrow_id) (bv1 : typed_value) (bv : typed_value) :
+      borrow_id * typed_value =
     if bid0 = bid1 then (
       (* If the merged value is not the same as the original value, we introduce
          an abstraction:
@@ -532,28 +525,29 @@ module MakeJoinMatcher (S : MatchJoinState) : PrimMatcher = struct
          do so, we won't introduce reborrows like above: the forward loop function
          will update [v], while the backward loop function will return nothing.
       *)
-      assert (not (value_has_borrows S.ctx bv.V.value));
+      assert (not (value_has_borrows S.ctx bv.value));
 
       if bv0 = bv1 then (
         assert (bv0 = bv);
         (bid0, bv))
       else
-        let rid = C.fresh_region_id () in
-        let nbid = C.fresh_borrow_id () in
+        let rid = fresh_region_id () in
+        let nbid = fresh_borrow_id () in
 
-        let kind = T.Mut in
-        let bv_ty = ety_no_regions_to_rty bv.V.ty in
-        let borrow_ty = mk_ref_ty (T.Var rid) bv_ty kind in
+        let kind = RMut in
+        let bv_ty = bv.ty in
+        assert (ty_no_regions bv_ty);
+        let borrow_ty = mk_ref_ty (RVar rid) bv_ty kind in
 
         let borrow_av =
           let ty = borrow_ty in
-          let value = V.ABorrow (V.AMutBorrow (bid0, mk_aignored bv_ty)) in
+          let value = ABorrow (AMutBorrow (bid0, mk_aignored bv_ty)) in
           mk_typed_avalue ty value
         in
 
         let loan_av =
           let ty = borrow_ty in
-          let value = V.ALoan (V.AMutLoan (nbid, mk_aignored bv_ty)) in
+          let value = ALoan (AMutLoan (nbid, mk_aignored bv_ty)) in
           mk_typed_avalue ty value
         in
 
@@ -562,13 +556,13 @@ module MakeJoinMatcher (S : MatchJoinState) : PrimMatcher = struct
         (* Generate the abstraction *)
         let abs =
           {
-            V.abs_id = C.fresh_abstraction_id ();
-            kind = V.Loop (S.loop_id, None, LoopSynthInput);
+            abs_id = fresh_abstraction_id ();
+            kind = Loop (S.loop_id, None, LoopSynthInput);
             can_end = true;
-            parents = V.AbstractionId.Set.empty;
+            parents = AbstractionId.Set.empty;
             original_parents = [];
-            regions = T.RegionId.Set.singleton rid;
-            ancestors_regions = T.RegionId.Set.empty;
+            regions = RegionId.Set.singleton rid;
+            ancestors_regions = RegionId.Set.empty;
             avalues;
           }
         in
@@ -583,41 +577,42 @@ module MakeJoinMatcher (S : MatchJoinState) : PrimMatcher = struct
            { MB bid0, MB bid1, ML bid2 }
          ]}
       *)
-      let rid = C.fresh_region_id () in
-      let bid2 = C.fresh_borrow_id () in
+      let rid = fresh_region_id () in
+      let bid2 = fresh_borrow_id () in
 
       (* Generate a fresh symbolic value for the borrowed value *)
       let _, bv_ty, kind = ty_as_ref ty in
-      let sv = mk_fresh_symbolic_typed_value_from_ety V.LoopJoin bv_ty in
-
-      let borrow_ty =
-        mk_ref_ty (T.Var rid) (ety_no_regions_to_rty bv_ty) kind
+      let sv =
+        mk_fresh_symbolic_typed_value_from_no_regions_ty LoopJoin bv_ty
       in
 
+      let borrow_ty = mk_ref_ty (RVar rid) bv_ty kind in
+
       (* Generate the avalues for the abstraction *)
-      let mk_aborrow (bid : V.borrow_id) (bv : V.typed_value) : V.typed_avalue =
-        let bv_ty = ety_no_regions_to_rty bv.V.ty in
-        let value = V.ABorrow (V.AMutBorrow (bid, mk_aignored bv_ty)) in
-        { V.value; ty = borrow_ty }
+      let mk_aborrow (bid : borrow_id) (bv : typed_value) : typed_avalue =
+        let bv_ty = bv.ty in
+        assert (ty_no_regions bv_ty);
+        let value = ABorrow (AMutBorrow (bid, mk_aignored bv_ty)) in
+        { value; ty = borrow_ty }
       in
       let borrows = [ mk_aborrow bid0 bv0; mk_aborrow bid1 bv1 ] in
 
-      let loan = V.AMutLoan (bid2, mk_aignored (ety_no_regions_to_rty bv_ty)) in
+      let loan = AMutLoan (bid2, mk_aignored bv_ty) in
       (* Note that an aloan has a borrow type *)
-      let loan = { V.value = V.ALoan loan; ty = borrow_ty } in
+      let loan : typed_avalue = { value = ALoan loan; ty = borrow_ty } in
 
       let avalues = List.append borrows [ loan ] in
 
       (* Generate the abstraction *)
       let abs =
         {
-          V.abs_id = C.fresh_abstraction_id ();
-          kind = V.Loop (S.loop_id, None, LoopSynthInput);
+          abs_id = fresh_abstraction_id ();
+          kind = Loop (S.loop_id, None, LoopSynthInput);
           can_end = true;
-          parents = V.AbstractionId.Set.empty;
+          parents = AbstractionId.Set.empty;
           original_parents = [];
-          regions = T.RegionId.Set.singleton rid;
-          ancestors_regions = T.RegionId.Set.empty;
+          regions = RegionId.Set.singleton rid;
+          ancestors_regions = RegionId.Set.empty;
           avalues;
         }
       in
@@ -626,20 +621,19 @@ module MakeJoinMatcher (S : MatchJoinState) : PrimMatcher = struct
       (* Return the new borrow *)
       (bid2, sv)
 
-  let match_shared_loans (_ : T.ety) (ids0 : V.loan_id_set)
-      (ids1 : V.loan_id_set) (sv : V.typed_value) :
-      V.loan_id_set * V.typed_value =
+  let match_shared_loans (_ : ety) (ids0 : loan_id_set) (ids1 : loan_id_set)
+      (sv : typed_value) : loan_id_set * typed_value =
     (* Check if the ids are the same - Rem.: we forbid the sets of loans
        to be different. However, if we dive inside data-structures (by
        using a shared borrow) the shared values might themselves contain
        shared loans, which need to be matched. For this reason, we destructure
        the shared values (see {!destructure_abs}).
     *)
-    let extra_ids_left = V.BorrowId.Set.diff ids0 ids1 in
-    let extra_ids_right = V.BorrowId.Set.diff ids1 ids0 in
-    if not (V.BorrowId.Set.is_empty extra_ids_left) then
+    let extra_ids_left = BorrowId.Set.diff ids0 ids1 in
+    let extra_ids_right = BorrowId.Set.diff ids1 ids0 in
+    if not (BorrowId.Set.is_empty extra_ids_left) then
       raise (ValueMatchFailure (LoansInLeft extra_ids_left));
-    if not (V.BorrowId.Set.is_empty extra_ids_right) then
+    if not (BorrowId.Set.is_empty extra_ids_right) then
       raise (ValueMatchFailure (LoansInRight extra_ids_right));
 
     (* This should always be true if we get here *)
@@ -649,16 +643,15 @@ module MakeJoinMatcher (S : MatchJoinState) : PrimMatcher = struct
     (* Return *)
     (ids, sv)
 
-  let match_mut_loans (_ : T.ety) (id0 : V.loan_id) (id1 : V.loan_id) :
-      V.loan_id =
+  let match_mut_loans (_ : ety) (id0 : loan_id) (id1 : loan_id) : loan_id =
     if id0 = id1 then id0
     else
       (* We forbid this case for now: if we get there, we force to end
          both borrows *)
       raise (ValueMatchFailure (LoanInLeft id0))
 
-  let match_symbolic_values (sv0 : V.symbolic_value) (sv1 : V.symbolic_value) :
-      V.symbolic_value =
+  let match_symbolic_values (sv0 : symbolic_value) (sv1 : symbolic_value) :
+      symbolic_value =
     let id0 = sv0.sv_id in
     let id1 = sv1.sv_id in
     if id0 = id1 then (
@@ -671,31 +664,30 @@ module MakeJoinMatcher (S : MatchJoinState) : PrimMatcher = struct
          borrows *)
       assert (not (ty_has_borrows S.ctx.type_context.type_infos sv0.sv_ty));
       (* We simply introduce a fresh symbolic value *)
-      mk_fresh_symbolic_value V.LoopJoin sv0.sv_ty)
+      mk_fresh_symbolic_value LoopJoin sv0.sv_ty)
 
-  let match_symbolic_with_other (left : bool) (sv : V.symbolic_value)
-      (v : V.typed_value) : V.typed_value =
+  let match_symbolic_with_other (left : bool) (sv : symbolic_value)
+      (v : typed_value) : typed_value =
     (* Check that:
        - there are no borrows in the symbolic value
        - there are no borrows in the "regular" value
        If there are loans in the regular value, raise an exception.
     *)
     assert (not (ty_has_borrows S.ctx.type_context.type_infos sv.sv_ty));
-    assert (not (value_has_borrows S.ctx v.V.value));
+    assert (not (value_has_borrows S.ctx v.value));
     let value_is_left = not left in
     (match InterpreterBorrowsCore.get_first_loan_in_value v with
     | None -> ()
-    | Some (SharedLoan (ids, _)) ->
+    | Some (VSharedLoan (ids, _)) ->
         if value_is_left then raise (ValueMatchFailure (LoansInLeft ids))
         else raise (ValueMatchFailure (LoansInRight ids))
-    | Some (MutLoan id) ->
+    | Some (VMutLoan id) ->
         if value_is_left then raise (ValueMatchFailure (LoanInLeft id))
         else raise (ValueMatchFailure (LoanInRight id)));
     (* Return a fresh symbolic value *)
-    mk_fresh_symbolic_typed_value V.LoopJoin sv.sv_ty
+    mk_fresh_symbolic_typed_value LoopJoin sv.sv_ty
 
-  let match_bottom_with_other (left : bool) (v : V.typed_value) : V.typed_value
-      =
+  let match_bottom_with_other (left : bool) (v : typed_value) : typed_value =
     (* If there are outer loans in the non-bottom value, raise an exception.
        Otherwise, convert it to an abstraction and return [Bottom].
     *)
@@ -708,15 +700,15 @@ module MakeJoinMatcher (S : MatchJoinState) : PrimMatcher = struct
     | Some (BorrowContent _) -> raise (Failure "Unreachable")
     | Some (LoanContent lc) -> (
         match lc with
-        | V.SharedLoan (ids, _) ->
+        | VSharedLoan (ids, _) ->
             if value_is_left then raise (ValueMatchFailure (LoansInLeft ids))
             else raise (ValueMatchFailure (LoansInRight ids))
-        | V.MutLoan id ->
+        | VMutLoan id ->
             if value_is_left then raise (ValueMatchFailure (LoanInLeft id))
             else raise (ValueMatchFailure (LoanInRight id)))
     | None ->
         (* Convert the value to an abstraction *)
-        let abs_kind = V.Loop (S.loop_id, None, LoopSynthInput) in
+        let abs_kind : abs_kind = Loop (S.loop_id, None, LoopSynthInput) in
         let can_end = true in
         let destructure_shared_values = true in
         let absl =
@@ -725,7 +717,7 @@ module MakeJoinMatcher (S : MatchJoinState) : PrimMatcher = struct
         in
         push_absl absl;
         (* Return [Bottom] *)
-        mk_bottom v.V.ty
+        mk_bottom v.ty
 
   (* As explained in comments: we don't use the join matcher to join avalues,
      only concrete values *)
@@ -782,12 +774,12 @@ struct
         (match_el msg m (Id.Set.elements ks0) (Id.Set.elements ks1))
   end
 
-  module GetSetRid = MkGetSetM (T.RegionId)
+  module GetSetRid = MkGetSetM (RegionId)
 
   let match_rid = GetSetRid.match_e "match_rid: " S.rid_map
   let match_rids = GetSetRid.match_es "match_rids: " S.rid_map
 
-  module GetSetBid = MkGetSetM (V.BorrowId)
+  module GetSetBid = MkGetSetM (BorrowId)
 
   let match_blid msg = GetSetBid.match_e msg S.blid_map
   let match_blidl msg = GetSetBid.match_el msg S.blid_map
@@ -817,8 +809,8 @@ struct
     if S.check_equiv then match_blids "match_loan_ids: "
     else GetSetBid.match_es "match_loan_ids: " S.loan_id_map
 
-  module GetSetSid = MkGetSetM (V.SymbolicValueId)
-  module GetSetAid = MkGetSetM (V.AbstractionId)
+  module GetSetSid = MkGetSetM (SymbolicValueId)
+  module GetSetAid = MkGetSetM (AbstractionId)
 
   let match_aid = GetSetAid.match_e "match_aid: " S.aid_map
   let match_aidl = GetSetAid.match_el "match_aidl: " S.aid_map
@@ -832,29 +824,29 @@ struct
     let match_distinct_types _ _ = raise (Distinct "match_rtys") in
     let match_regions r0 r1 =
       match (r0, r1) with
-      | T.Static, T.Static -> r1
-      | Var rid0, Var rid1 ->
+      | RStatic, RStatic -> r1
+      | RVar rid0, RVar rid1 ->
           let rid = match_rid rid0 rid1 in
-          Var rid
+          RVar rid
       | _ -> raise (Distinct "match_rtys")
     in
     match_types match_distinct_types match_regions ty0 ty1
 
-  let match_distinct_literals (ty : T.ety) (_ : V.literal) (_ : V.literal) :
-      V.typed_value =
-    mk_fresh_symbolic_typed_value_from_ety V.LoopJoin ty
+  let match_distinct_literals (ty : ety) (_ : literal) (_ : literal) :
+      typed_value =
+    mk_fresh_symbolic_typed_value_from_no_regions_ty LoopJoin ty
 
-  let match_distinct_adts (_ty : T.ety) (_adt0 : V.adt_value)
-      (_adt1 : V.adt_value) : V.typed_value =
+  let match_distinct_adts (_ty : ety) (_adt0 : adt_value) (_adt1 : adt_value) :
+      typed_value =
     raise (Distinct "match_distinct_adts")
 
   let match_shared_borrows
-      (match_typed_values : V.typed_value -> V.typed_value -> V.typed_value)
-      (_ty : T.ety) (bid0 : V.borrow_id) (bid1 : V.borrow_id) : V.borrow_id =
+      (match_typed_values : typed_value -> typed_value -> typed_value)
+      (_ty : ety) (bid0 : borrow_id) (bid1 : borrow_id) : borrow_id =
     log#ldebug
       (lazy
         ("MakeCheckEquivMatcher: match_shared_borrows: " ^ "bid0: "
-       ^ V.BorrowId.to_string bid0 ^ ", bid1: " ^ V.BorrowId.to_string bid1));
+       ^ BorrowId.to_string bid0 ^ ", bid1: " ^ BorrowId.to_string bid1));
 
     let bid = match_borrow_id bid0 bid1 in
     (* If we don't check for equivalence (i.e., we apply a fixed-point),
@@ -878,33 +870,31 @@ struct
     in
     bid
 
-  let match_mut_borrows (_ty : T.ety) (bid0 : V.borrow_id)
-      (_bv0 : V.typed_value) (bid1 : V.borrow_id) (_bv1 : V.typed_value)
-      (bv : V.typed_value) : V.borrow_id * V.typed_value =
+  let match_mut_borrows (_ty : ety) (bid0 : borrow_id) (_bv0 : typed_value)
+      (bid1 : borrow_id) (_bv1 : typed_value) (bv : typed_value) :
+      borrow_id * typed_value =
     let bid = match_borrow_id bid0 bid1 in
     (bid, bv)
 
-  let match_shared_loans (_ : T.ety) (ids0 : V.loan_id_set)
-      (ids1 : V.loan_id_set) (sv : V.typed_value) :
-      V.loan_id_set * V.typed_value =
+  let match_shared_loans (_ : ety) (ids0 : loan_id_set) (ids1 : loan_id_set)
+      (sv : typed_value) : loan_id_set * typed_value =
     let ids = match_loan_ids ids0 ids1 in
     (ids, sv)
 
-  let match_mut_loans (_ : T.ety) (bid0 : V.loan_id) (bid1 : V.loan_id) :
-      V.loan_id =
+  let match_mut_loans (_ : ety) (bid0 : loan_id) (bid1 : loan_id) : loan_id =
     match_loan_id bid0 bid1
 
-  let match_symbolic_values (sv0 : V.symbolic_value) (sv1 : V.symbolic_value) :
-      V.symbolic_value =
+  let match_symbolic_values (sv0 : symbolic_value) (sv1 : symbolic_value) :
+      symbolic_value =
     let id0 = sv0.sv_id in
     let id1 = sv1.sv_id in
 
     log#ldebug
       (lazy
         ("MakeCheckEquivMatcher: match_symbolic_values: " ^ "sv0: "
-        ^ V.SymbolicValueId.to_string id0
+        ^ SymbolicValueId.to_string id0
         ^ ", sv1: "
-        ^ V.SymbolicValueId.to_string id1));
+        ^ SymbolicValueId.to_string id1));
 
     (* If we don't check for equivalence, we also update the map from sids
        to values *)
@@ -913,81 +903,80 @@ struct
       let sv_id =
         GetSetSid.match_e "match_symbolic_values: ids: " S.sid_map id0 id1
       in
-      let sv_ty = match_rtys sv0.V.sv_ty sv1.V.sv_ty in
+      let sv_ty = match_rtys sv0.sv_ty sv1.sv_ty in
       let sv_kind =
-        if sv0.V.sv_kind = sv1.V.sv_kind then sv0.V.sv_kind
+        if sv0.sv_kind = sv1.sv_kind then sv0.sv_kind
         else raise (Distinct "match_symbolic_values: sv_kind")
       in
-      let sv = { V.sv_id; sv_ty; sv_kind } in
+      let sv = { sv_id; sv_ty; sv_kind } in
       sv
     else (
       (* Check: fixed values are fixed *)
-      assert (id0 = id1 || not (V.SymbolicValueId.InjSubst.mem id0 !S.sid_map));
+      assert (id0 = id1 || not (SymbolicValueId.InjSubst.mem id0 !S.sid_map));
 
       (* Update the symbolic value mapping *)
       let sv1 = mk_typed_value_from_symbolic_value sv1 in
 
       (* Update the symbolic value mapping *)
       S.sid_to_value_map :=
-        V.SymbolicValueId.Map.add_strict id0 sv1 !S.sid_to_value_map;
+        SymbolicValueId.Map.add_strict id0 sv1 !S.sid_to_value_map;
 
       (* Return - the returned value is not used: we can return  whatever
          we want *)
       sv0)
 
-  let match_symbolic_with_other (left : bool) (sv : V.symbolic_value)
-      (v : V.typed_value) : V.typed_value =
+  let match_symbolic_with_other (left : bool) (sv : symbolic_value)
+      (v : typed_value) : typed_value =
     if S.check_equiv then raise (Distinct "match_symbolic_with_other")
     else (
       assert left;
       let id = sv.sv_id in
       (* Check: fixed values are fixed *)
-      assert (not (V.SymbolicValueId.InjSubst.mem id !S.sid_map));
+      assert (not (SymbolicValueId.InjSubst.mem id !S.sid_map));
       (* Update the binding for the target symbolic value *)
       S.sid_to_value_map :=
-        V.SymbolicValueId.Map.add_strict id v !S.sid_to_value_map;
+        SymbolicValueId.Map.add_strict id v !S.sid_to_value_map;
       (* Return - the returned value is not used, so we can return whatever we want *)
       v)
 
-  let match_bottom_with_other (left : bool) (v : V.typed_value) : V.typed_value
-      =
+  let match_bottom_with_other (left : bool) (v : typed_value) : typed_value =
     (* It can happen that some variables get initialized in some branches
        and not in some others, which causes problems when matching. *)
     (* TODO: the returned value is not used, while it should: in generality it
        should be ok to match a fixed-point with the environment we get at
        a continue, where the fixed point contains some bottom values. *)
-    if left && not (value_has_loans_or_borrows S.ctx v.V.value) then
-      mk_bottom v.V.ty
+    if left && not (value_has_loans_or_borrows S.ctx v.value) then
+      mk_bottom v.ty
     else raise (Distinct "match_bottom_with_other")
 
   let match_distinct_aadts _ _ _ _ _ = raise (Distinct "match_distinct_adts")
 
   let match_ashared_borrows _ty0 bid0 _ty1 bid1 ty =
     let bid = match_borrow_id bid0 bid1 in
-    let value = V.ABorrow (V.ASharedBorrow bid) in
-    { V.value; ty }
+    let value = ABorrow (ASharedBorrow bid) in
+    { value; ty }
 
   let match_amut_borrows _ty0 bid0 _av0 _ty1 bid1 _av1 ty av =
     let bid = match_borrow_id bid0 bid1 in
-    let value = V.ABorrow (V.AMutBorrow (bid, av)) in
-    { V.value; ty }
+    let value = ABorrow (AMutBorrow (bid, av)) in
+    { value; ty }
 
   let match_ashared_loans _ty0 ids0 _v0 _av0 _ty1 ids1 _v1 _av1 ty v av =
     let bids = match_loan_ids ids0 ids1 in
-    let value = V.ALoan (V.ASharedLoan (bids, v, av)) in
-    { V.value; ty }
+    let value = ALoan (ASharedLoan (bids, v, av)) in
+    { value; ty }
 
   let match_amut_loans _ty0 id0 _av0 _ty1 id1 _av1 ty av =
     log#ldebug
       (lazy
         ("MakeCheckEquivMatcher:match_amut_loans:" ^ "\n- id0: "
-       ^ V.BorrowId.to_string id0 ^ "\n- id1: " ^ V.BorrowId.to_string id1
-       ^ "\n- ty: " ^ rty_to_string S.ctx ty ^ "\n- av: "
+       ^ BorrowId.to_string id0 ^ "\n- id1: " ^ BorrowId.to_string id1
+       ^ "\n- ty: " ^ ty_to_string S.ctx ty ^ "\n- av: "
         ^ typed_avalue_to_string S.ctx av));
 
     let id = match_loan_id id0 id1 in
-    let value = V.ALoan (V.AMutLoan (id, av)) in
-    { V.value; ty }
+    let value = ALoan (AMutLoan (id, av)) in
+    { value; ty }
 
   let match_avalues v0 v1 =
     log#ldebug
@@ -1000,9 +989,9 @@ struct
 end
 
 let match_ctxs (check_equiv : bool) (fixed_ids : ids_sets)
-    (lookup_shared_value_in_ctx0 : V.BorrowId.id -> V.typed_value)
-    (lookup_shared_value_in_ctx1 : V.BorrowId.id -> V.typed_value)
-    (ctx0 : C.eval_ctx) (ctx1 : C.eval_ctx) : ids_maps option =
+    (lookup_shared_value_in_ctx0 : BorrowId.id -> typed_value)
+    (lookup_shared_value_in_ctx1 : BorrowId.id -> typed_value) (ctx0 : eval_ctx)
+    (ctx1 : eval_ctx) : ids_maps option =
   log#ldebug
     (lazy
       ("match_ctxs:\n\n- fixed_ids:\n" ^ show_ids_sets fixed_ids
@@ -1019,35 +1008,35 @@ let match_ctxs (check_equiv : bool) (fixed_ids : ids_sets)
         (Id.InjSubst.of_list (List.map (fun x -> (x, x)) (Id.Set.elements ids)))
   end in
   let rid_map =
-    let module IdMap = IdMap (T.RegionId) in
+    let module IdMap = IdMap (RegionId) in
     IdMap.mk_map_ref fixed_ids.rids
   in
   let blid_map =
-    let module IdMap = IdMap (V.BorrowId) in
+    let module IdMap = IdMap (BorrowId) in
     IdMap.mk_map_ref fixed_ids.blids
   in
   let borrow_id_map =
-    let module IdMap = IdMap (V.BorrowId) in
+    let module IdMap = IdMap (BorrowId) in
     IdMap.mk_map_ref fixed_ids.borrow_ids
   in
   let loan_id_map =
-    let module IdMap = IdMap (V.BorrowId) in
+    let module IdMap = IdMap (BorrowId) in
     IdMap.mk_map_ref fixed_ids.loan_ids
   in
   let aid_map =
-    let module IdMap = IdMap (V.AbstractionId) in
+    let module IdMap = IdMap (AbstractionId) in
     IdMap.mk_map_ref fixed_ids.aids
   in
   let sid_map =
-    let module IdMap = IdMap (V.SymbolicValueId) in
+    let module IdMap = IdMap (SymbolicValueId) in
     IdMap.mk_map_ref fixed_ids.sids
   in
   (* In case we don't try to check equivalence but want to compute a mapping
      from a source context to a target context, we use a map from symbolic
      value ids to values (rather than to ids).
   *)
-  let sid_to_value_map : V.typed_value V.SymbolicValueId.Map.t ref =
-    ref V.SymbolicValueId.Map.empty
+  let sid_to_value_map : typed_value SymbolicValueId.Map.t ref =
+    ref SymbolicValueId.Map.empty
   in
 
   let module S : MatchCheckEquivState = struct
@@ -1071,12 +1060,12 @@ let match_ctxs (check_equiv : bool) (fixed_ids : ids_sets)
   (* Small utility: check that ids are fixed/mapped to themselves *)
   let ids_are_fixed (ids : ids_sets) : bool =
     let { aids; blids = _; borrow_ids; loan_ids; dids; rids; sids } = ids in
-    V.AbstractionId.Set.subset aids fixed_ids.aids
-    && V.BorrowId.Set.subset borrow_ids fixed_ids.borrow_ids
-    && V.BorrowId.Set.subset loan_ids fixed_ids.loan_ids
-    && C.DummyVarId.Set.subset dids fixed_ids.dids
-    && T.RegionId.Set.subset rids fixed_ids.rids
-    && V.SymbolicValueId.Set.subset sids fixed_ids.sids
+    AbstractionId.Set.subset aids fixed_ids.aids
+    && BorrowId.Set.subset borrow_ids fixed_ids.borrow_ids
+    && BorrowId.Set.subset loan_ids fixed_ids.loan_ids
+    && DummyVarId.Set.subset dids fixed_ids.dids
+    && RegionId.Set.subset rids fixed_ids.rids
+    && SymbolicValueId.Set.subset sids fixed_ids.sids
   in
 
   (* We need to pick a context for some functions like [match_typed_values]:
@@ -1088,9 +1077,9 @@ let match_ctxs (check_equiv : bool) (fixed_ids : ids_sets)
   let ctx = ctx0 in
 
   (* Rem.: this function raises exceptions of type [Distinct] *)
-  let match_abstractions (abs0 : V.abs) (abs1 : V.abs) : unit =
+  let match_abstractions (abs0 : abs) (abs1 : abs) : unit =
     let {
-      V.abs_id = abs_id0;
+      abs_id = abs_id0;
       kind = kind0;
       can_end = can_end0;
       parents = parents0;
@@ -1103,7 +1092,7 @@ let match_ctxs (check_equiv : bool) (fixed_ids : ids_sets)
     in
 
     let {
-      V.abs_id = abs_id1;
+      abs_id = abs_id1;
       kind = kind1;
       can_end = can_end1;
       parents = parents1;
@@ -1134,18 +1123,18 @@ let match_ctxs (check_equiv : bool) (fixed_ids : ids_sets)
   in
 
   (* Rem.: this function raises exceptions of type [Distinct] *)
-  let rec match_envs (env0 : C.env) (env1 : C.env) : unit =
+  let rec match_envs (env0 : env) (env1 : env) : unit =
     log#ldebug
       (lazy
         ("match_ctxs: match_envs:\n\n- fixed_ids:\n" ^ show_ids_sets fixed_ids
        ^ "\n\n- rid_map: "
-        ^ T.RegionId.InjSubst.show_t !rid_map
+        ^ RegionId.InjSubst.show_t !rid_map
         ^ "\n- blid_map: "
-        ^ V.BorrowId.InjSubst.show_t !blid_map
+        ^ BorrowId.InjSubst.show_t !blid_map
         ^ "\n- sid_map: "
-        ^ V.SymbolicValueId.InjSubst.show_t !sid_map
+        ^ SymbolicValueId.InjSubst.show_t !sid_map
         ^ "\n- aid_map: "
-        ^ V.AbstractionId.InjSubst.show_t !aid_map
+        ^ AbstractionId.InjSubst.show_t !aid_map
         ^ "\n\n- ctx0:\n"
         ^ eval_ctx_to_string_no_filter { ctx0 with env = List.rev env0 }
         ^ "\n\n- ctx1:\n"
@@ -1153,11 +1142,10 @@ let match_ctxs (check_equiv : bool) (fixed_ids : ids_sets)
         ^ "\n\n"));
 
     match (env0, env1) with
-    | ( C.Var (C.DummyBinder b0, v0) :: env0',
-        C.Var (C.DummyBinder b1, v1) :: env1' ) ->
+    | EBinding (BDummy b0, v0) :: env0', EBinding (BDummy b1, v1) :: env1' ->
         (* Sanity check: if the dummy value is an old value, the bindings must
            be the same and their values equal (and the borrows/loans/symbolic *)
-        if C.DummyVarId.Set.mem b0 fixed_ids.dids then (
+        if DummyVarId.Set.mem b0 fixed_ids.dids then (
           (* Fixed values: the values must be equal *)
           assert (b0 = b1);
           assert (v0 = v1);
@@ -1168,17 +1156,16 @@ let match_ctxs (check_equiv : bool) (fixed_ids : ids_sets)
            are the identity actually) *)
         let _ = M.match_typed_values ctx v0 v1 in
         match_envs env0' env1'
-    | C.Var (C.VarBinder b0, v0) :: env0', C.Var (C.VarBinder b1, v1) :: env1'
-      ->
+    | EBinding (BVar b0, v0) :: env0', EBinding (BVar b1, v1) :: env1' ->
         assert (b0 = b1);
         (* Match the values *)
         let _ = M.match_typed_values ctx v0 v1 in
         (* Continue *)
         match_envs env0' env1'
-    | C.Abs abs0 :: env0', C.Abs abs1 :: env1' ->
+    | EAbs abs0 :: env0', EAbs abs1 :: env1' ->
         log#ldebug (lazy "match_ctxs: match_envs: matching abs");
         (* Same as for the dummy values: there are two cases *)
-        if V.AbstractionId.Set.mem abs0.abs_id fixed_ids.aids then (
+        if AbstractionId.Set.mem abs0.abs_id fixed_ids.aids then (
           log#ldebug (lazy "match_ctxs: match_envs: matching abs: fixed abs");
           (* Still in the prefix: the abstractions must be the same *)
           assert (abs0 = abs1);
@@ -1211,7 +1198,7 @@ let match_ctxs (check_equiv : bool) (fixed_ids : ids_sets)
     let env1 = List.rev ctx1.env in
     let env0, env1 =
       match (env0, env1) with
-      | C.Frame :: env0, C.Frame :: env1 -> (env0, env1)
+      | EFrame :: env0, EFrame :: env1 -> (env0, env1)
       | _ -> raise (Failure "Unreachable")
     in
 
@@ -1232,18 +1219,18 @@ let match_ctxs (check_equiv : bool) (fixed_ids : ids_sets)
     log#ldebug (lazy ("match_ctxs: distinct: " ^ msg));
     None
 
-let ctxs_are_equivalent (fixed_ids : ids_sets) (ctx0 : C.eval_ctx)
-    (ctx1 : C.eval_ctx) : bool =
+let ctxs_are_equivalent (fixed_ids : ids_sets) (ctx0 : eval_ctx)
+    (ctx1 : eval_ctx) : bool =
   let check_equivalent = true in
   let lookup_shared_value _ = raise (Failure "Unreachable") in
   Option.is_some
     (match_ctxs check_equivalent fixed_ids lookup_shared_value
        lookup_shared_value ctx0 ctx1)
 
-let match_ctx_with_target (config : C.config) (loop_id : V.LoopId.id)
+let match_ctx_with_target (config : config) (loop_id : LoopId.id)
     (is_loop_entry : bool) (fp_bl_maps : borrow_loan_corresp)
-    (fp_input_svalues : V.SymbolicValueId.id list) (fixed_ids : ids_sets)
-    (src_ctx : C.eval_ctx) : st_cm_fun =
+    (fp_input_svalues : SymbolicValueId.id list) (fixed_ids : ids_sets)
+    (src_ctx : eval_ctx) : st_cm_fun =
  fun cf tgt_ctx ->
   (* Debug *)
   log#ldebug
@@ -1274,8 +1261,8 @@ let match_ctx_with_target (config : C.config) (loop_id : V.LoopId.id)
         ^ env_to_string tgt_ctx filt_tgt_env));
 
     (* Remove the abstractions *)
-    let filter (ee : C.env_elem) : bool =
-      match ee with Var _ -> true | Abs _ | Frame -> false
+    let filter (ee : env_elem) : bool =
+      match ee with EBinding _ -> true | EAbs _ | EFrame -> false
     in
     let filt_src_env = List.filter filter filt_src_env in
     let filt_tgt_env = List.filter filter filt_tgt_env in
@@ -1304,11 +1291,11 @@ let match_ctx_with_target (config : C.config) (loop_id : V.LoopId.id)
         List.iter
           (fun (var0, var1) ->
             match (var0, var1) with
-            | C.Var (C.DummyBinder b0, v0), C.Var (C.DummyBinder b1, v1) ->
+            | EBinding (BDummy b0, v0), EBinding (BDummy b1, v1) ->
                 assert (b0 = b1);
                 let _ = M.match_typed_values ctx v0 v1 in
                 ()
-            | C.Var (C.VarBinder b0, v0), C.Var (C.VarBinder b1, v1) ->
+            | EBinding (BVar b0, v0), EBinding (BVar b1, v1) ->
                 assert (b0 = b1);
                 let _ = M.match_typed_values ctx v0 v1 in
                 ()
@@ -1361,10 +1348,10 @@ let match_ctx_with_target (config : C.config) (loop_id : V.LoopId.id)
       let check_equiv = false in
       let fixed_ids = ids_sets_empty_borrows_loans fixed_ids in
       let open InterpreterBorrowsCore in
-      let lookup_shared_loan lid ctx : V.typed_value =
+      let lookup_shared_loan lid ctx : typed_value =
         match snd (lookup_loan ek_all lid ctx) with
-        | Concrete (V.SharedLoan (_, v)) -> v
-        | Abstract (V.ASharedLoan (_, v, _)) -> v
+        | Concrete (VSharedLoan (_, v)) -> v
+        | Abstract (ASharedLoan (_, v, _)) -> v
         | _ -> raise (Failure "Unreachable")
       in
       let lookup_in_src id = lookup_shared_loan id src_ctx in
@@ -1375,10 +1362,10 @@ let match_ctx_with_target (config : C.config) (loop_id : V.LoopId.id)
            filt_src_ctx filt_tgt_ctx)
     in
     let tgt_to_src_borrow_map =
-      V.BorrowId.Map.of_list
+      BorrowId.Map.of_list
         (List.map
            (fun (x, y) -> (y, x))
-           (V.BorrowId.InjSubst.bindings src_to_tgt_maps.borrow_id_map))
+           (BorrowId.InjSubst.bindings src_to_tgt_maps.borrow_id_map))
     in
 
     (* Debug *)
@@ -1392,7 +1379,7 @@ let match_ctx_with_target (config : C.config) (loop_id : V.LoopId.id)
         ^ eval_ctx_to_string_no_filter filt_src_ctx
         ^ "\n\n- new_absl:\n"
         ^ eval_ctx_to_string
-            { src_ctx with C.env = List.map (fun abs -> C.Abs abs) new_absl }
+            { src_ctx with env = List.map (fun abs -> EAbs abs) new_absl }
         ^ "\n\n- fixed_ids:\n" ^ show_ids_sets fixed_ids ^ "\n\n- fp_bl_maps:\n"
         ^ show_borrow_loan_corresp fp_bl_maps
         ^ "\n\n- src_to_tgt_maps: "
@@ -1449,26 +1436,26 @@ let match_ctx_with_target (config : C.config) (loop_id : V.LoopId.id)
     (* First, compute the set of borrows which appear in the fresh abstractions
        of the fixed-point: we want to introduce fresh ids only for those. *)
     let new_absl_ids, _ = compute_absl_ids new_absl in
-    let src_fresh_borrows_map = ref V.BorrowId.Map.empty in
+    let src_fresh_borrows_map = ref BorrowId.Map.empty in
     let visit_tgt =
       object
-        inherit [_] C.map_eval_ctx
+        inherit [_] map_eval_ctx
 
         method! visit_borrow_id _ id =
           (* Map the borrow, if it needs to be mapped *)
           if
             (* We map the borrows for which we computed a mapping *)
-            V.BorrowId.InjSubst.Set.mem id
-              (V.BorrowId.InjSubst.elements src_to_tgt_maps.borrow_id_map)
+            BorrowId.InjSubst.Set.mem id
+              (BorrowId.InjSubst.elements src_to_tgt_maps.borrow_id_map)
             (* And which have corresponding loans in the fresh fixed-point abstractions *)
-            && V.BorrowId.Set.mem
-                 (V.BorrowId.Map.find id tgt_to_src_borrow_map)
+            && BorrowId.Set.mem
+                 (BorrowId.Map.find id tgt_to_src_borrow_map)
                  new_absl_ids.loan_ids
           then (
-            let src_id = V.BorrowId.Map.find id tgt_to_src_borrow_map in
-            let nid = C.fresh_borrow_id () in
+            let src_id = BorrowId.Map.find id tgt_to_src_borrow_map in
+            let nid = fresh_borrow_id () in
             src_fresh_borrows_map :=
-              V.BorrowId.Map.add src_id nid !src_fresh_borrows_map;
+              BorrowId.Map.add src_id nid !src_fresh_borrows_map;
             nid)
           else id
       end
@@ -1479,7 +1466,7 @@ let match_ctx_with_target (config : C.config) (loop_id : V.LoopId.id)
       (lazy
         ("match_ctx_with_target: cf_introduce_loop_fp_abs: \
           src_fresh_borrows_map:\n"
-        ^ V.BorrowId.Map.show V.BorrowId.to_string !src_fresh_borrows_map
+        ^ BorrowId.Map.show BorrowId.to_string !src_fresh_borrows_map
         ^ "\n"));
 
     (* Rem.: we don't update the symbolic values. It is not necessary
@@ -1504,48 +1491,44 @@ let match_ctx_with_target (config : C.config) (loop_id : V.LoopId.id)
          abs@2 { MB l5, ML l6 }
        ]}
     *)
-    let region_id_map = ref T.RegionId.Map.empty in
+    let region_id_map = ref RegionId.Map.empty in
     let get_rid rid =
-      match T.RegionId.Map.find_opt rid !region_id_map with
+      match RegionId.Map.find_opt rid !region_id_map with
       | Some rid -> rid
       | None ->
-          let nid = C.fresh_region_id () in
-          region_id_map := T.RegionId.Map.add rid nid !region_id_map;
+          let nid = fresh_region_id () in
+          region_id_map := RegionId.Map.add rid nid !region_id_map;
           nid
     in
     let visit_src =
       object
-        inherit [_] C.map_eval_ctx as super
+        inherit [_] map_eval_ctx as super
 
         method! visit_borrow_id _ bid =
           log#ldebug
             (lazy
               ("match_ctx_with_target: cf_introduce_loop_fp_abs: \
-                visit_borrow_id: " ^ V.BorrowId.to_string bid ^ "\n"));
+                visit_borrow_id: " ^ BorrowId.to_string bid ^ "\n"));
 
           (* Lookup the id of the loan corresponding to this borrow *)
           let src_lid =
-            V.BorrowId.InjSubst.find bid fp_bl_maps.borrow_to_loan_id_map
+            BorrowId.InjSubst.find bid fp_bl_maps.borrow_to_loan_id_map
           in
 
           log#ldebug
             (lazy
               ("match_ctx_with_target: cf_introduce_loop_fp_abs: looked up \
-                src_lid: "
-              ^ V.BorrowId.to_string src_lid
-              ^ "\n"));
+                src_lid: " ^ BorrowId.to_string src_lid ^ "\n"));
 
           (* Lookup the tgt borrow id to which this borrow was mapped *)
           let tgt_bid =
-            V.BorrowId.InjSubst.find src_lid src_to_tgt_maps.borrow_id_map
+            BorrowId.InjSubst.find src_lid src_to_tgt_maps.borrow_id_map
           in
 
           log#ldebug
             (lazy
               ("match_ctx_with_target: cf_introduce_loop_fp_abs: looked up \
-                tgt_bid: "
-              ^ V.BorrowId.to_string tgt_bid
-              ^ "\n"));
+                tgt_bid: " ^ BorrowId.to_string tgt_bid ^ "\n"));
 
           tgt_bid
 
@@ -1553,39 +1536,39 @@ let match_ctx_with_target (config : C.config) (loop_id : V.LoopId.id)
           log#ldebug
             (lazy
               ("match_ctx_with_target: cf_introduce_loop_fp_abs: \
-                visit_loan_id: " ^ V.BorrowId.to_string id ^ "\n"));
+                visit_loan_id: " ^ BorrowId.to_string id ^ "\n"));
           (* Map the borrow - rem.: we mapped the borrows *in the values*,
              meaning we know how to map the *corresponding loans in the
              abstractions* *)
-          match V.BorrowId.Map.find_opt id !src_fresh_borrows_map with
+          match BorrowId.Map.find_opt id !src_fresh_borrows_map with
           | None ->
               (* No mapping: this means that the borrow was mapped when
                  we matched values (it doesn't come from a fresh abstraction)
                  and because of this, it should actually be mapped to itself *)
               assert (
-                V.BorrowId.InjSubst.find id src_to_tgt_maps.borrow_id_map = id);
+                BorrowId.InjSubst.find id src_to_tgt_maps.borrow_id_map = id);
               id
           | Some id -> id
 
-        method! visit_symbolic_value_id _ _ = C.fresh_symbolic_value_id ()
-        method! visit_abstraction_id _ _ = C.fresh_abstraction_id ()
+        method! visit_symbolic_value_id _ _ = fresh_symbolic_value_id ()
+        method! visit_abstraction_id _ _ = fresh_abstraction_id ()
         method! visit_region_id _ id = get_rid id
 
         (** We also need to change the abstraction kind *)
         method! visit_abs env abs =
           match abs.kind with
-          | V.Loop (loop_id', rg_id, kind) ->
+          | Loop (loop_id', rg_id, kind) ->
               assert (loop_id' = loop_id);
-              assert (kind = V.LoopSynthInput);
+              assert (kind = LoopSynthInput);
               let can_end = false in
-              let kind = V.Loop (loop_id, rg_id, V.LoopCall) in
+              let kind : abs_kind = Loop (loop_id, rg_id, LoopCall) in
               let abs = { abs with kind; can_end } in
               super#visit_abs env abs
           | _ -> super#visit_abs env abs
       end
     in
     let new_absl = List.map (visit_src#visit_abs ()) new_absl in
-    let new_absl = List.map (fun abs -> C.Abs abs) new_absl in
+    let new_absl = List.map (fun abs -> EAbs abs) new_absl in
 
     (* Add the abstractions from the target context to the source context *)
     let nenv = List.append new_absl tgt_ctx.env in
@@ -1602,19 +1585,17 @@ let match_ctx_with_target (config : C.config) (loop_id : V.LoopId.id)
 
     (* End all the borrows which appear in the *new* abstractions *)
     let new_borrows =
-      V.BorrowId.Set.of_list
-        (List.map snd (V.BorrowId.Map.bindings !src_fresh_borrows_map))
+      BorrowId.Set.of_list
+        (List.map snd (BorrowId.Map.bindings !src_fresh_borrows_map))
     in
     let cc = InterpreterBorrows.end_borrows config new_borrows in
 
     (* Compute the loop input values *)
     let input_values =
-      V.SymbolicValueId.Map.of_list
+      SymbolicValueId.Map.of_list
         (List.map
            (fun sid ->
-             ( sid,
-               V.SymbolicValueId.Map.find sid src_to_tgt_maps.sid_to_value_map
-             ))
+             (sid, SymbolicValueId.Map.find sid src_to_tgt_maps.sid_to_value_map))
            fp_input_svalues)
     in
 
diff --git a/compiler/InterpreterLoopsMatchCtxs.mli b/compiler/InterpreterLoopsMatchCtxs.mli
index 20b997ce..bf29af79 100644
--- a/compiler/InterpreterLoopsMatchCtxs.mli
+++ b/compiler/InterpreterLoopsMatchCtxs.mli
@@ -4,15 +4,8 @@
     to check if two contexts are equivalent (modulo conversion).
  *)
 
-module T = Types
-module PV = PrimitiveValues
-module V = Values
-module E = Expressions
-module C = Contexts
-module Subst = Substitute
-module A = LlbcAst
-module Inv = Invariants
-module S = SynthesizeSymbolic
+open Values
+open Contexts
 open Cps
 open InterpreterUtils
 open InterpreterLoopsCore
@@ -26,7 +19,7 @@ open InterpreterLoopsCore
     - [env]
  *)
 val compute_abs_borrows_loans_maps :
-  bool -> (V.abs -> bool) -> C.env -> abs_borrows_loans_maps
+  bool -> (abs -> bool) -> env -> abs_borrows_loans_maps
 
 (** Generic functor to implement matching functions between values, environments,
     etc.
@@ -100,10 +93,10 @@ module MakeCheckEquivMatcher : functor (_ : MatchCheckEquivState) ->
 val match_ctxs :
   bool ->
   ids_sets ->
-  (V.loan_id -> V.typed_value) ->
-  (V.loan_id -> V.typed_value) ->
-  C.eval_ctx ->
-  C.eval_ctx ->
+  (loan_id -> typed_value) ->
+  (loan_id -> typed_value) ->
+  eval_ctx ->
+  eval_ctx ->
   ids_maps option
 
 (** Compute whether two contexts are equivalent modulo an identifier substitution.
@@ -142,7 +135,7 @@ val match_ctxs :
     - [ctx0]
     - [ctx1]
  *)
-val ctxs_are_equivalent : ids_sets -> C.eval_ctx -> C.eval_ctx -> bool
+val ctxs_are_equivalent : ids_sets -> eval_ctx -> eval_ctx -> bool
 
 (** Match a context with a target context.
 
@@ -291,11 +284,11 @@ val ctxs_are_equivalent : ids_sets -> C.eval_ctx -> C.eval_ctx -> bool
    - [src_ctx]
  *)
 val match_ctx_with_target :
-  C.config ->
-  V.loop_id ->
+  config ->
+  loop_id ->
   bool ->
   borrow_loan_corresp ->
-  V.symbolic_value_id list ->
+  symbolic_value_id list ->
   ids_sets ->
-  C.eval_ctx ->
+  eval_ctx ->
   st_cm_fun
diff --git a/compiler/InterpreterPaths.ml b/compiler/InterpreterPaths.ml
index 2a277c91..729a3577 100644
--- a/compiler/InterpreterPaths.ml
+++ b/compiler/InterpreterPaths.ml
@@ -1,10 +1,7 @@
-module T = Types
-module V = Values
-module E = Expressions
-module C = Contexts
-module Subst = Substitute
-module Assoc = AssociatedTypes
-module L = Logging
+open Types
+open Values
+open Expressions
+open Contexts
 open Cps
 open ValuesUtils
 open InterpreterUtils
@@ -14,7 +11,7 @@ open InterpreterExpansion
 module Synth = SynthesizeSymbolic
 
 (** The local logger *)
-let log = L.paths_log
+let log = Logging.paths_log
 
 (** Paths *)
 
@@ -25,26 +22,26 @@ let log = L.paths_log
     TODO: compare with borrow_lres?
 *)
 type path_fail_kind =
-  | FailSharedLoan of V.BorrowId.Set.t
+  | FailSharedLoan of BorrowId.Set.t
       (** Failure because we couldn't go inside a shared loan *)
-  | FailMutLoan of V.BorrowId.id
+  | FailMutLoan of BorrowId.id
       (** Failure because we couldn't go inside a mutable loan *)
-  | FailReservedMutBorrow of V.BorrowId.id
+  | FailReservedMutBorrow of BorrowId.id
       (** Failure because we couldn't go inside a reserved mutable borrow
           (which should get activated) *)
-  | FailSymbolic of int * V.symbolic_value
+  | FailSymbolic of int * symbolic_value
       (** Failure because we need to enter a symbolic value (and thus need to
           expand it).
           We return the number of elements which remained in the path when we
           reached the error - this allows to retrieve the path prefix, which
           is useful for the synthesis. *)
-  | FailBottom of int * E.projection_elem * T.ety
+  | FailBottom of int * projection_elem * ety
       (** Failure because we need to enter an any value - we can expand Bottom
           values if they are left values. We return the number of elements which
           remained in the path when we reached the error - this allows to
           properly update the Bottom value, if needs be.
        *)
-  | FailBorrow of V.borrow_content
+  | FailBorrow of borrow_content
       (** We got stuck because we couldn't enter a borrow *)
 [@@deriving show]
 
@@ -56,7 +53,7 @@ type path_fail_kind =
 type 'a path_access_result = ('a, path_fail_kind) result
 (** The result of reading from/writing to a place *)
 
-type updated_read_value = { read : V.typed_value; updated : V.typed_value }
+type updated_read_value = { read : typed_value; updated : typed_value }
 
 type projection_access = {
   enter_shared_loans : bool;
@@ -71,10 +68,10 @@ type projection_access = {
     
     TODO: use exceptions?
  *)
-let rec access_projection (access : projection_access) (ctx : C.eval_ctx)
+let rec access_projection (access : projection_access) (ctx : eval_ctx)
     (* Function to (eventually) update the value we find *)
-      (update : V.typed_value -> V.typed_value) (p : E.projection)
-    (v : V.typed_value) : (C.eval_ctx * updated_read_value) path_access_result =
+      (update : typed_value -> typed_value) (p : projection) (v : typed_value) :
+    (eval_ctx * updated_read_value) path_access_result =
   (* For looking up/updating shared loans *)
   let ek : exploration_kind =
     { enter_shared_loans = true; enter_mut_borrows = true; enter_abs = true }
@@ -86,8 +83,8 @@ let rec access_projection (access : projection_access) (ctx : C.eval_ctx)
       if nv.ty <> v.ty then (
         log#lerror
           (lazy
-            ("Not the same type:\n- nv.ty: " ^ T.show_ety nv.ty ^ "\n- v.ty: "
-           ^ T.show_ety v.ty));
+            ("Not the same type:\n- nv.ty: " ^ show_ety nv.ty ^ "\n- v.ty: "
+           ^ show_ety v.ty));
         raise
           (Failure
              "Assertion failed: new value doesn't have the same type as its \
@@ -95,55 +92,55 @@ let rec access_projection (access : projection_access) (ctx : C.eval_ctx)
       Ok (ctx, { read = v; updated = nv })
   | pe :: p' -> (
       (* Match on the projection element and the value *)
-      match (pe, v.V.value, v.V.ty) with
+      match (pe, v.value, v.ty) with
       | ( Field ((ProjAdt (_, _) as proj_kind), field_id),
-          V.Adt adt,
-          T.Adt (type_id, _) ) -> (
+          VAdt adt,
+          TAdt (type_id, _) ) -> (
           (* Check consistency *)
           (match (proj_kind, type_id) with
-          | ProjAdt (def_id, opt_variant_id), T.AdtId def_id' ->
+          | ProjAdt (def_id, opt_variant_id), TAdtId def_id' ->
               assert (def_id = def_id');
               assert (opt_variant_id = adt.variant_id)
           | _ -> raise (Failure "Unreachable"));
           (* Actually project *)
-          let fv = T.FieldId.nth adt.field_values field_id in
+          let fv = FieldId.nth adt.field_values field_id in
           match access_projection access ctx update p' fv with
           | Error err -> Error err
           | Ok (ctx, res) ->
               (* Update the field value *)
               let nvalues =
-                T.FieldId.update_nth adt.field_values field_id res.updated
+                FieldId.update_nth adt.field_values field_id res.updated
               in
-              let nadt = V.Adt { adt with V.field_values = nvalues } in
+              let nadt = VAdt { adt with field_values = nvalues } in
               let updated = { v with value = nadt } in
               Ok (ctx, { res with updated }))
       (* Tuples *)
-      | Field (ProjTuple arity, field_id), V.Adt adt, T.Adt (T.Tuple, _) -> (
+      | Field (ProjTuple arity, field_id), VAdt adt, TAdt (TTuple, _) -> (
           assert (arity = List.length adt.field_values);
-          let fv = T.FieldId.nth adt.field_values field_id in
+          let fv = FieldId.nth adt.field_values field_id in
           (* Project *)
           match access_projection access ctx update p' fv with
           | Error err -> Error err
           | Ok (ctx, res) ->
               (* Update the field value *)
               let nvalues =
-                T.FieldId.update_nth adt.field_values field_id res.updated
+                FieldId.update_nth adt.field_values field_id res.updated
               in
-              let ntuple = V.Adt { adt with field_values = nvalues } in
+              let ntuple = VAdt { adt with field_values = nvalues } in
               let updated = { v with value = ntuple } in
               Ok (ctx, { res with updated })
           (* If we reach Bottom, it may mean we need to expand an uninitialized
            * enumeration value *))
-      | Field ((ProjAdt (_, _) | ProjTuple _), _), V.Bottom, _ ->
+      | Field ((ProjAdt (_, _) | ProjTuple _), _), VBottom, _ ->
           Error (FailBottom (1 + List.length p', pe, v.ty))
       (* Symbolic value: needs to be expanded *)
-      | _, Symbolic sp, _ ->
+      | _, VSymbolic sp, _ ->
           (* Expand the symbolic value *)
           Error (FailSymbolic (1 + List.length p', sp))
       (* Box dereferencement *)
       | ( DerefBox,
-          Adt { variant_id = None; field_values = [ bv ] },
-          T.Adt (T.Assumed T.Box, _) ) -> (
+          VAdt { variant_id = None; field_values = [ bv ] },
+          TAdt (TAssumed TBox, _) ) -> (
           (* We allow moving outside of boxes. In practice, this kind of
            * manipulations should happen only inside unsafe code, so
            * it shouldn't happen due to user code, and we leverage it
@@ -156,20 +153,20 @@ let rec access_projection (access : projection_access) (ctx : C.eval_ctx)
                 {
                   v with
                   value =
-                    V.Adt { variant_id = None; field_values = [ res.updated ] };
+                    VAdt { variant_id = None; field_values = [ res.updated ] };
                 }
               in
               Ok (ctx, { res with updated = nv }))
       (* Borrows *)
-      | Deref, V.Borrow bc, _ -> (
+      | Deref, VBorrow bc, _ -> (
           match bc with
-          | V.SharedBorrow bid ->
+          | VSharedBorrow bid ->
               (* Lookup the loan content, and explore from there *)
               if access.lookup_shared_borrows then
                 match lookup_loan ek bid ctx with
-                | _, Concrete (V.MutLoan _) ->
+                | _, Concrete (VMutLoan _) ->
                     raise (Failure "Expected a shared loan")
-                | _, Concrete (V.SharedLoan (bids, sv)) -> (
+                | _, Concrete (VSharedLoan (bids, sv)) -> (
                     (* Explore the shared value *)
                     match access_projection access ctx update p' sv with
                     | Error err -> Error err
@@ -178,23 +175,23 @@ let rec access_projection (access : projection_access) (ctx : C.eval_ctx)
                            by {!access_projection} *)
                         let ctx =
                           update_loan ek bid
-                            (V.SharedLoan (bids, res.updated))
+                            (VSharedLoan (bids, res.updated))
                             ctx
                         in
                         (* Return - note that we don't need to update the borrow itself *)
                         Ok (ctx, { res with updated = v }))
                 | ( _,
                     Abstract
-                      ( V.AMutLoan (_, _)
-                      | V.AEndedMutLoan
+                      ( AMutLoan (_, _)
+                      | AEndedMutLoan
                           { given_back = _; child = _; given_back_meta = _ }
-                      | V.AEndedSharedLoan (_, _)
-                      | V.AIgnoredMutLoan (_, _)
-                      | V.AEndedIgnoredMutLoan
+                      | AEndedSharedLoan (_, _)
+                      | AIgnoredMutLoan (_, _)
+                      | AEndedIgnoredMutLoan
                           { given_back = _; child = _; given_back_meta = _ }
-                      | V.AIgnoredSharedLoan _ ) ) ->
+                      | AIgnoredSharedLoan _ ) ) ->
                     raise (Failure "Expected a shared (abstraction) loan")
-                | _, Abstract (V.ASharedLoan (bids, sv, _av)) -> (
+                | _, Abstract (ASharedLoan (bids, sv, _av)) -> (
                     (* Explore the shared value *)
                     match access_projection access ctx update p' sv with
                     | Error err -> Error err
@@ -202,37 +199,34 @@ let rec access_projection (access : projection_access) (ctx : C.eval_ctx)
                         (* Relookup the child avalue *)
                         let av =
                           match lookup_loan ek bid ctx with
-                          | _, Abstract (V.ASharedLoan (_, _, av)) -> av
+                          | _, Abstract (ASharedLoan (_, _, av)) -> av
                           | _ -> raise (Failure "Unexpected")
                         in
                         (* Update the shared loan with the new value returned
                              by {!access_projection} *)
                         let ctx =
                           update_aloan ek bid
-                            (V.ASharedLoan (bids, res.updated, av))
+                            (ASharedLoan (bids, res.updated, av))
                             ctx
                         in
                         (* Return - note that we don't need to update the borrow itself *)
                         Ok (ctx, { res with updated = v }))
               else Error (FailBorrow bc)
-          | V.ReservedMutBorrow bid -> Error (FailReservedMutBorrow bid)
-          | V.MutBorrow (bid, bv) ->
+          | VReservedMutBorrow bid -> Error (FailReservedMutBorrow bid)
+          | VMutBorrow (bid, bv) ->
               if access.enter_mut_borrows then
                 match access_projection access ctx update p' bv with
                 | Error err -> Error err
                 | Ok (ctx, res) ->
                     let nv =
-                      {
-                        v with
-                        value = V.Borrow (V.MutBorrow (bid, res.updated));
-                      }
+                      { v with value = VBorrow (VMutBorrow (bid, res.updated)) }
                     in
                     Ok (ctx, { res with updated = nv })
               else Error (FailBorrow bc))
-      | _, V.Loan lc, _ -> (
+      | _, VLoan lc, _ -> (
           match lc with
-          | V.MutLoan bid -> Error (FailMutLoan bid)
-          | V.SharedLoan (bids, sv) ->
+          | VMutLoan bid -> Error (FailMutLoan bid)
+          | VSharedLoan (bids, sv) ->
               (* If we can enter shared loan, we ignore the loan. Pay attention
                  to the fact that we need to reexplore the *whole* place (i.e,
                  we mustn't ignore the current projection element *)
@@ -241,18 +235,15 @@ let rec access_projection (access : projection_access) (ctx : C.eval_ctx)
                 | Error err -> Error err
                 | Ok (ctx, res) ->
                     let nv =
-                      {
-                        v with
-                        value = V.Loan (V.SharedLoan (bids, res.updated));
-                      }
+                      { v with value = VLoan (VSharedLoan (bids, res.updated)) }
                     in
                     Ok (ctx, { res with updated = nv })
               else Error (FailSharedLoan bids))
-      | (_, (V.Literal _ | V.Adt _ | V.Bottom | V.Borrow _), _) as r ->
+      | (_, (VLiteral _ | VAdt _ | VBottom | VBorrow _), _) as r ->
           let pe, v, ty = r in
-          let pe = "- pe: " ^ E.show_projection_elem pe in
-          let v = "- v:\n" ^ V.show_value v in
-          let ty = "- ty:\n" ^ T.show_ety ty in
+          let pe = "- pe: " ^ show_projection_elem pe in
+          let v = "- v:\n" ^ show_value v in
+          let ty = "- ty:\n" ^ show_ety ty in
           log#serror ("Inconsistent projection:\n" ^ pe ^ "\n" ^ v ^ "\n" ^ ty);
           raise (Failure "Inconsistent projection"))
 
@@ -264,16 +255,16 @@ let rec access_projection (access : projection_access) (ctx : C.eval_ctx)
  *)
 let access_place (access : projection_access)
     (* Function to (eventually) update the value we find *)
-      (update : V.typed_value -> V.typed_value) (p : E.place) (ctx : C.eval_ctx)
-    : (C.eval_ctx * V.typed_value) path_access_result =
+      (update : typed_value -> typed_value) (p : place) (ctx : eval_ctx) :
+    (eval_ctx * typed_value) path_access_result =
   (* Lookup the variable's value *)
-  let value = C.ctx_lookup_var_value ctx p.var_id in
+  let value = ctx_lookup_var_value ctx p.var_id in
   (* Apply the projection *)
   match access_projection access ctx update p.projection value with
   | Error err -> Error err
   | Ok (ctx, res) ->
       (* Update the value *)
-      let ctx = C.ctx_update_var_value ctx p.var_id res.updated in
+      let ctx = ctx_update_var_value ctx p.var_id res.updated in
       (* Return *)
       Ok (ctx, res.read)
 
@@ -309,8 +300,8 @@ let access_kind_to_projection_access (access : access_kind) : projection_access
     Note that we only access the value at the place, and do not check that
     the value is "well-formed" (for instance that it doesn't contain bottoms).
  *)
-let try_read_place (access : access_kind) (p : E.place) (ctx : C.eval_ctx) :
-    V.typed_value path_access_result =
+let try_read_place (access : access_kind) (p : place) (ctx : eval_ctx) :
+    typed_value path_access_result =
   let access = access_kind_to_projection_access access in
   (* The update function is the identity *)
   let update v = v in
@@ -324,22 +315,21 @@ let try_read_place (access : access_kind) (p : E.place) (ctx : C.eval_ctx) :
         if ctx1 <> ctx then (
           let msg =
             "Unexpected environment update:\nNew environment:\n"
-            ^ C.show_env ctx1.env ^ "\n\nOld environment:\n"
-            ^ C.show_env ctx.env
+            ^ show_env ctx1.env ^ "\n\nOld environment:\n" ^ show_env ctx.env
           in
           log#serror msg;
           raise (Failure "Unexpected environment update"));
       Ok read_value
 
-let read_place (access : access_kind) (p : E.place) (ctx : C.eval_ctx) :
-    V.typed_value =
+let read_place (access : access_kind) (p : place) (ctx : eval_ctx) : typed_value
+    =
   match try_read_place access p ctx with
   | Error e -> raise (Failure ("Unreachable: " ^ show_path_fail_kind e))
   | Ok v -> v
 
 (** Attempt to update the value at a given place *)
-let try_write_place (access : access_kind) (p : E.place) (nv : V.typed_value)
-    (ctx : C.eval_ctx) : C.eval_ctx path_access_result =
+let try_write_place (access : access_kind) (p : place) (nv : typed_value)
+    (ctx : eval_ctx) : eval_ctx path_access_result =
   let access = access_kind_to_projection_access access in
   (* The update function substitutes the value with the new value *)
   let update _ = nv in
@@ -349,41 +339,42 @@ let try_write_place (access : access_kind) (p : E.place) (nv : V.typed_value)
       (* We ignore the read value *)
       Ok ctx
 
-let write_place (access : access_kind) (p : E.place) (nv : V.typed_value)
-    (ctx : C.eval_ctx) : C.eval_ctx =
+let write_place (access : access_kind) (p : place) (nv : typed_value)
+    (ctx : eval_ctx) : eval_ctx =
   match try_write_place access p nv ctx with
   | Error e -> raise (Failure ("Unreachable: " ^ show_path_fail_kind e))
   | Ok ctx -> ctx
 
-let compute_expanded_bottom_adt_value (ctx : C.eval_ctx)
-    (def_id : T.TypeDeclId.id) (opt_variant_id : T.VariantId.id option)
-    (generics : T.egeneric_args) : V.typed_value =
+let compute_expanded_bottom_adt_value (ctx : eval_ctx) (def_id : TypeDeclId.id)
+    (opt_variant_id : VariantId.id option) (generics : generic_args) :
+    typed_value =
+  assert (TypesUtils.generic_args_only_erased_regions generics);
   (* Lookup the definition and check if it is an enumeration - it
      should be an enumeration if and only if the projection element
      is a field projection with *some* variant id. Retrieve the list
      of fields at the same time. *)
-  let def = C.ctx_lookup_type_decl ctx def_id in
-  assert (List.length generics.regions = List.length def.T.generics.regions);
+  let def = ctx_lookup_type_decl ctx def_id in
+  assert (List.length generics.regions = List.length def.generics.regions);
   (* Compute the field types *)
   let field_types =
-    Assoc.type_decl_get_inst_norm_field_etypes ctx def opt_variant_id generics
+    AssociatedTypes.type_decl_get_inst_norm_field_etypes ctx def opt_variant_id
+      generics
   in
   (* Initialize the expanded value *)
   let fields = List.map mk_bottom field_types in
-  let av = V.Adt { variant_id = opt_variant_id; field_values = fields } in
-  let ty = T.Adt (T.AdtId def_id, generics) in
-  { V.value = av; V.ty }
+  let av = VAdt { variant_id = opt_variant_id; field_values = fields } in
+  let ty = TAdt (TAdtId def_id, generics) in
+  { value = av; ty }
 
-let compute_expanded_bottom_tuple_value (field_types : T.ety list) :
-    V.typed_value =
+let compute_expanded_bottom_tuple_value (field_types : ety list) : typed_value =
   (* Generate the field values *)
   let fields = List.map mk_bottom field_types in
-  let v = V.Adt { variant_id = None; field_values = fields } in
+  let v = VAdt { variant_id = None; field_values = fields } in
   let generics = TypesUtils.mk_generic_args [] field_types [] [] in
-  let ty = T.Adt (T.Tuple, generics) in
-  { V.value = v; V.ty }
+  let ty = TAdt (TTuple, generics) in
+  { value = v; ty }
 
-(** Auxiliary helper to expand {!V.Bottom} values.
+(** Auxiliary helper to expand {!Bottom} values.
 
     During compilation, rustc desaggregates the ADT initializations. The
     consequence is that the following rust code:
@@ -399,19 +390,19 @@ let compute_expanded_bottom_tuple_value (field_types : T.ety list) :
     ]}
 
     The consequence is that we may sometimes need to write fields to values
-    which are currently {!V.Bottom}. When doing this, we first expand the value
+    which are currently {!Bottom}. When doing this, we first expand the value
     to, say, [Cons Bottom Bottom] (note that field projection contains information
     about which variant we should project to, which is why we *can* set the
     variant index when writing one of its fields).
 *)
-let expand_bottom_value_from_projection (access : access_kind) (p : E.place)
-    (remaining_pes : int) (pe : E.projection_elem) (ty : T.ety)
-    (ctx : C.eval_ctx) : C.eval_ctx =
+let expand_bottom_value_from_projection (access : access_kind) (p : place)
+    (remaining_pes : int) (pe : projection_elem) (ty : ety) (ctx : eval_ctx) :
+    eval_ctx =
   (* Debugging *)
   log#ldebug
     (lazy
       ("expand_bottom_value_from_projection:\n" ^ "pe: "
-     ^ E.show_projection_elem pe ^ "\n" ^ "ty: " ^ T.show_ety ty));
+     ^ show_projection_elem pe ^ "\n" ^ "ty: " ^ show_ety ty));
   (* Prepare the update: we need to take the proper prefix of the place
      during whose evaluation we got stuck *)
   let projection' =
@@ -421,41 +412,40 @@ let expand_bottom_value_from_projection (access : access_kind) (p : E.place)
   in
   let p' = { p with projection = projection' } in
   (* Compute the expanded value.
-     The type of the {!V.Bottom} value should be a tuple or an ADT.
+     The type of the {!Bottom} value should be a tuple or an AD
      Note that the projection element we got stuck at should be a
-     field projection, and gives the variant id if the {!V.Bottom} value
+     field projection, and gives the variant id if the {!Bottom} value
      is an enumeration value.
      Also, the expanded value should be the proper ADT variant or a tuple
-     with the proper arity, with all the fields initialized to {!V.Bottom}
+     with the proper arity, with all the fields initialized to {!Bottom}
   *)
   let nv =
     match (pe, ty) with
     (* "Regular" ADTs *)
     | ( Field (ProjAdt (def_id, opt_variant_id), _),
-        T.Adt (T.AdtId def_id', generics) ) ->
+        TAdt (TAdtId def_id', generics) ) ->
         assert (def_id = def_id');
         compute_expanded_bottom_adt_value ctx def_id opt_variant_id generics
     (* Tuples *)
     | ( Field (ProjTuple arity, _),
-        T.Adt
-          ( T.Tuple,
-            { T.regions = []; types; const_generics = []; trait_refs = [] } ) )
-      ->
+        TAdt
+          (TTuple, { regions = []; types; const_generics = []; trait_refs = [] })
+      ) ->
         assert (arity = List.length types);
         (* Generate the field values *)
         compute_expanded_bottom_tuple_value types
     | _ ->
         raise
           (Failure
-             ("Unreachable: " ^ E.show_projection_elem pe ^ ", " ^ T.show_ety ty))
+             ("Unreachable: " ^ show_projection_elem pe ^ ", " ^ show_ety ty))
   in
   (* Update the context by inserting the expanded value at the proper place *)
   match try_write_place access p' nv ctx with
   | Ok ctx -> ctx
   | Error _ -> raise (Failure "Unreachable")
 
-let rec update_ctx_along_read_place (config : C.config) (access : access_kind)
-    (p : E.place) : cm_fun =
+let rec update_ctx_along_read_place (config : config) (access : access_kind)
+    (p : place) : cm_fun =
  fun cf ctx ->
   (* Attempt to read the place: if it fails, update the environment and retry *)
   match try_read_place access p ctx with
@@ -476,14 +466,14 @@ let rec update_ctx_along_read_place (config : C.config) (access : access_kind)
             expand_symbolic_value_no_branching config sp
               (Some (Synth.mk_mplace prefix ctx))
         | FailBottom (_, _, _) ->
-            (* We can't expand {!V.Bottom} values while reading them *)
+            (* We can't expand {!Bottom} values while reading them *)
             raise (Failure "Found [Bottom] while reading a place")
         | FailBorrow _ -> raise (Failure "Could not read a borrow")
       in
       comp cc (update_ctx_along_read_place config access p) cf ctx
 
-let rec update_ctx_along_write_place (config : C.config) (access : access_kind)
-    (p : E.place) : cm_fun =
+let rec update_ctx_along_write_place (config : config) (access : access_kind)
+    (p : place) : cm_fun =
  fun cf ctx ->
   (* Attempt to *read* (yes, *read*: we check the access to the place, and
      write to it later) the place: if it fails, update the environment and retry *)
@@ -501,7 +491,7 @@ let rec update_ctx_along_write_place (config : C.config) (access : access_kind)
             expand_symbolic_value_no_branching config sp
               (Some (Synth.mk_mplace p ctx))
         | FailBottom (remaining_pes, pe, ty) ->
-            (* Expand the {!V.Bottom} value *)
+            (* Expand the {!Bottom} value *)
             fun cf ctx ->
              let ctx =
                expand_bottom_value_from_projection access p remaining_pes pe ty
@@ -516,8 +506,8 @@ let rec update_ctx_along_write_place (config : C.config) (access : access_kind)
 (** Small utility used to break control-flow *)
 exception UpdateCtx of cm_fun
 
-let rec end_loans_at_place (config : C.config) (access : access_kind)
-    (p : E.place) : cm_fun =
+let rec end_loans_at_place (config : config) (access : access_kind) (p : place)
+    : cm_fun =
  fun cf ctx ->
   (* Iterator to explore a value and update the context whenever we find
    * loans.
@@ -526,28 +516,28 @@ let rec end_loans_at_place (config : C.config) (access : access_kind)
    * *)
   let obj =
     object
-      inherit [_] V.iter_typed_value as super
+      inherit [_] iter_typed_value as super
 
       method! visit_borrow_content env bc =
         match bc with
-        | V.SharedBorrow _ | V.MutBorrow (_, _) ->
+        | VSharedBorrow _ | VMutBorrow (_, _) ->
             (* Nothing special to do *) super#visit_borrow_content env bc
-        | V.ReservedMutBorrow bid ->
+        | VReservedMutBorrow bid ->
             (* We need to activate reserved borrows *)
             let cc = promote_reserved_mut_borrow config bid in
             raise (UpdateCtx cc)
 
       method! visit_loan_content env lc =
         match lc with
-        | V.SharedLoan (bids, v) -> (
+        | VSharedLoan (bids, v) -> (
             (* End the loans if we need a modification access, otherwise dive into
                the shared value *)
             match access with
-            | Read -> super#visit_SharedLoan env bids v
+            | Read -> super#visit_VSharedLoan env bids v
             | Write | Move ->
                 let cc = end_borrows config bids in
                 raise (UpdateCtx cc))
-        | V.MutLoan bid ->
+        | VMutLoan bid ->
             (* We always need to end mutable borrows *)
             let cc = end_borrow config bid in
             raise (UpdateCtx cc)
@@ -571,20 +561,20 @@ let rec end_loans_at_place (config : C.config) (access : access_kind)
      * a recursive call to reinspect the value *)
     comp cc (end_loans_at_place config access p) cf ctx
 
-let drop_outer_loans_at_lplace (config : C.config) (p : E.place) : cm_fun =
+let drop_outer_loans_at_lplace (config : config) (p : place) : cm_fun =
  fun cf ctx ->
   (* Move the current value in the place outside of this place and into
    * a dummy variable *)
   let access = Write in
   let v = read_place access p ctx in
-  let ctx = write_place access p (mk_bottom v.V.ty) ctx in
-  let dummy_id = C.fresh_dummy_var_id () in
-  let ctx = C.ctx_push_dummy_var ctx dummy_id v in
+  let ctx = write_place access p (mk_bottom v.ty) ctx in
+  let dummy_id = fresh_dummy_var_id () in
+  let ctx = ctx_push_dummy_var ctx dummy_id v in
   (* Auxiliary function *)
   let rec drop : cm_fun =
    fun cf ctx ->
     (* Read the value *)
-    let v = C.ctx_lookup_dummy_var ctx dummy_id in
+    let v = ctx_lookup_dummy_var ctx dummy_id in
     (* Check if there are loans or borrows to end *)
     let with_borrows = false in
     match get_first_outer_loan_or_borrow_in_value with_borrows v with
@@ -595,8 +585,8 @@ let drop_outer_loans_at_lplace (config : C.config) (p : E.place) : cm_fun =
         (* There are: end them then retry *)
         let cc =
           match c with
-          | LoanContent (V.SharedLoan (bids, _)) -> end_borrows config bids
-          | LoanContent (V.MutLoan bid) -> end_borrow config bid
+          | LoanContent (VSharedLoan (bids, _)) -> end_borrows config bids
+          | LoanContent (VMutLoan bid) -> end_borrow config bid
           | BorrowContent _ -> raise (Failure "Unreachable")
         in
         (* Retry *)
@@ -608,7 +598,7 @@ let drop_outer_loans_at_lplace (config : C.config) (p : E.place) : cm_fun =
   let cc =
     comp cc (fun cf ctx ->
         (* Pop *)
-        let ctx, v = C.ctx_remove_dummy_var ctx dummy_id in
+        let ctx, v = ctx_remove_dummy_var ctx dummy_id in
         (* Reinsert *)
         let ctx = write_place access p v ctx in
         (* Sanity check *)
@@ -619,8 +609,8 @@ let drop_outer_loans_at_lplace (config : C.config) (p : E.place) : cm_fun =
   (* Continue *)
   cc cf ctx
 
-let prepare_lplace (config : C.config) (p : E.place)
-    (cf : V.typed_value -> m_fun) : m_fun =
+let prepare_lplace (config : config) (p : place) (cf : typed_value -> m_fun) :
+    m_fun =
  fun ctx ->
   log#ldebug
     (lazy
diff --git a/compiler/InterpreterPaths.mli b/compiler/InterpreterPaths.mli
index 0ff8063f..3e29b810 100644
--- a/compiler/InterpreterPaths.mli
+++ b/compiler/InterpreterPaths.mli
@@ -1,13 +1,8 @@
-module T = Types
-module V = Values
-module E = Expressions
-module C = Contexts
-module Subst = Substitute
-module Assoc = AssociatedTypes
-module L = Logging
+open Types
+open Values
+open Expressions
+open Contexts
 open Cps
-open InterpreterExpansion
-module Synth = SynthesizeSymbolic
 
 type access_kind = Read | Write | Move
 
@@ -18,13 +13,13 @@ type access_kind = Read | Write | Move
     updates the environment (by ending borrows, expanding symbolic values, etc.)
     until it manages to fully access the provided place.
  *)
-val update_ctx_along_read_place : C.config -> access_kind -> E.place -> cm_fun
+val update_ctx_along_read_place : config -> access_kind -> place -> cm_fun
 
 (** Update the environment to be able to write to a place.
 
     See {!update_ctx_along_read_place}.
 *)
-val update_ctx_along_write_place : C.config -> access_kind -> E.place -> cm_fun
+val update_ctx_along_write_place : config -> access_kind -> place -> cm_fun
 
 (** Read the value at a given place.
 
@@ -34,7 +29,7 @@ val update_ctx_along_write_place : C.config -> access_kind -> E.place -> cm_fun
     Note that we only access the value at the place, and do not check that
     the value is "well-formed" (for instance that it doesn't contain bottoms).
  *)
-val read_place : access_kind -> E.place -> C.eval_ctx -> V.typed_value
+val read_place : access_kind -> place -> eval_ctx -> typed_value
 
 (** Update the value at a given place.
 
@@ -45,23 +40,25 @@ val read_place : access_kind -> E.place -> C.eval_ctx -> V.typed_value
     the overwritten value contains borrows, loans, etc. and will simply
     overwrite it.
  *)
-val write_place :
-  access_kind -> E.place -> V.typed_value -> C.eval_ctx -> C.eval_ctx
+val write_place : access_kind -> place -> typed_value -> eval_ctx -> eval_ctx
 
 (** Compute an expanded tuple ⊥ value.
 
     [compute_expanded_bottom_tuple_value [ty0, ..., tyn]] returns
     [(⊥:ty0, ..., ⊥:tyn)]
  *)
-val compute_expanded_bottom_tuple_value : T.ety list -> V.typed_value
+val compute_expanded_bottom_tuple_value : ety list -> typed_value
 
-(** Compute an expanded ADT ⊥ value *)
+(** Compute an expanded ADT ⊥ value.
+
+    The types in the generics should use erased regions.
+  *)
 val compute_expanded_bottom_adt_value :
-  C.eval_ctx ->
-  T.TypeDeclId.id ->
-  T.VariantId.id option ->
-  T.egeneric_args ->
-  V.typed_value
+  eval_ctx ->
+  TypeDeclId.id ->
+  VariantId.id option ->
+  generic_args ->
+  typed_value
 
 (** Drop (end) outer loans at a given place, which should be seen as an l-value
     (we will write to it later, but need to drop the loans before writing).
@@ -76,7 +73,7 @@ val compute_expanded_bottom_adt_value :
     that the place is *inside* a borrow, if we end the borrow, we won't be able
     to reinsert the value back).
  *)
-val drop_outer_loans_at_lplace : C.config -> E.place -> cm_fun
+val drop_outer_loans_at_lplace : config -> place -> cm_fun
 
 (** End the loans at a given place: read the value, if it contains a loan,
     end this loan, repeat.
@@ -87,7 +84,7 @@ val drop_outer_loans_at_lplace : C.config -> E.place -> cm_fun
     when moving values, we can't move a value which contains loans and thus need
     to end them, etc.
  *)
-val end_loans_at_place : C.config -> access_kind -> E.place -> cm_fun
+val end_loans_at_place : config -> access_kind -> place -> cm_fun
 
 (** Small utility.
 
@@ -98,4 +95,4 @@ val end_loans_at_place : C.config -> access_kind -> E.place -> cm_fun
     place. This value should not contain any outer loan (and we check it is the
     case). Note that this value is very likely to contain ⊥ subvalues.
   *)
-val prepare_lplace : C.config -> E.place -> (V.typed_value -> m_fun) -> m_fun
+val prepare_lplace : config -> place -> (typed_value -> m_fun) -> m_fun
diff --git a/compiler/InterpreterProjectors.ml b/compiler/InterpreterProjectors.ml
index 9e0c2b75..4dc53586 100644
--- a/compiler/InterpreterProjectors.ml
+++ b/compiler/InterpreterProjectors.ml
@@ -1,38 +1,36 @@
-module T = Types
-module V = Values
-module E = Expressions
-module C = Contexts
+open Types
+open Values
+open Contexts
 module Subst = Substitute
 module Assoc = AssociatedTypes
-module L = Logging
 open TypesUtils
 open InterpreterUtils
 open InterpreterBorrowsCore
 
 (** The local logger *)
-let log = L.projectors_log
+let log = Logging.projectors_log
 
-let rec apply_proj_borrows_on_shared_borrow (ctx : C.eval_ctx)
-    (fresh_reborrow : V.BorrowId.id -> V.BorrowId.id)
-    (regions : T.RegionId.Set.t) (v : V.typed_value) (ty : T.rty) :
-    V.abstract_shared_borrows =
-  (* Sanity check - TODO: move this elsewhere (here we perform the check at every
+(** [ty] shouldn't contain erased regions *)
+let rec apply_proj_borrows_on_shared_borrow (ctx : eval_ctx)
+    (fresh_reborrow : BorrowId.id -> BorrowId.id) (regions : RegionId.Set.t)
+    (v : typed_value) (ty : rty) : abstract_shared_borrows =
+  (* Sanity check - TODO: move those elsewhere (here we perform the check at every
    * recursive call which is a bit overkill...) *)
   let ety = Subst.erase_regions ty in
-  assert (ety = v.V.ty);
+  assert (ty_is_rty ty && ety = v.ty);
   (* Project - if there are no regions from the abstraction in the type, return [_] *)
   if not (ty_has_regions_in_set regions ty) then []
   else
-    match (v.V.value, ty) with
-    | V.Literal _, T.Literal _ -> []
-    | V.Adt adt, T.Adt (id, generics) ->
+    match (v.value, ty) with
+    | VLiteral _, TLiteral _ -> []
+    | VAdt adt, TAdt (id, generics) ->
         (* Retrieve the types of the fields *)
         let field_types =
           Assoc.ctx_adt_value_get_inst_norm_field_rtypes ctx adt id generics
         in
 
         (* Project over the field values *)
-        let fields_types = List.combine adt.V.field_values field_types in
+        let fields_types = List.combine adt.field_values field_types in
         let proj_fields =
           List.map
             (fun (fv, fty) ->
@@ -41,33 +39,33 @@ let rec apply_proj_borrows_on_shared_borrow (ctx : C.eval_ctx)
             fields_types
         in
         List.concat proj_fields
-    | V.Bottom, _ -> raise (Failure "Unreachable")
-    | V.Borrow bc, T.Ref (r, ref_ty, kind) ->
+    | VBottom, _ -> raise (Failure "Unreachable")
+    | VBorrow bc, TRef (r, ref_ty, kind) ->
         (* Retrieve the bid of the borrow and the asb of the projected borrowed value *)
         let bid, asb =
           (* Not in the set: dive *)
           match (bc, kind) with
-          | V.MutBorrow (bid, bv), T.Mut ->
+          | VMutBorrow (bid, bv), RMut ->
               (* Apply the projection on the borrowed value *)
               let asb =
                 apply_proj_borrows_on_shared_borrow ctx fresh_reborrow regions
                   bv ref_ty
               in
               (bid, asb)
-          | V.SharedBorrow bid, T.Shared ->
+          | VSharedBorrow bid, RShared ->
               (* Lookup the shared value *)
               let ek = ek_all in
               let sv = lookup_loan ek bid ctx in
               let asb =
                 match sv with
-                | _, Concrete (V.SharedLoan (_, sv))
-                | _, Abstract (V.ASharedLoan (_, sv, _)) ->
+                | _, Concrete (VSharedLoan (_, sv))
+                | _, Abstract (ASharedLoan (_, sv, _)) ->
                     apply_proj_borrows_on_shared_borrow ctx fresh_reborrow
                       regions sv ref_ty
                 | _ -> raise (Failure "Unexpected")
               in
               (bid, asb)
-          | V.ReservedMutBorrow _, _ ->
+          | VReservedMutBorrow _, _ ->
               raise
                 (Failure
                    "Can't apply a proj_borrow over a reserved mutable borrow")
@@ -78,39 +76,38 @@ let rec apply_proj_borrows_on_shared_borrow (ctx : C.eval_ctx)
            * we never project over static regions) *)
           if region_in_set r regions then
             let bid' = fresh_reborrow bid in
-            V.AsbBorrow bid' :: asb
+            AsbBorrow bid' :: asb
           else asb
         in
         asb
-    | V.Loan _, _ -> raise (Failure "Unreachable")
-    | V.Symbolic s, _ ->
+    | VLoan _, _ -> raise (Failure "Unreachable")
+    | VSymbolic s, _ ->
         (* Check that the projection doesn't contain ended regions *)
-        assert (
-          not (projections_intersect s.V.sv_ty ctx.ended_regions ty regions));
-        [ V.AsbProjReborrows (s, ty) ]
+        assert (not (projections_intersect s.sv_ty ctx.ended_regions ty regions));
+        [ AsbProjReborrows (s, ty) ]
     | _ -> raise (Failure "Unreachable")
 
-let rec apply_proj_borrows (check_symbolic_no_ended : bool) (ctx : C.eval_ctx)
-    (fresh_reborrow : V.BorrowId.id -> V.BorrowId.id)
-    (regions : T.RegionId.Set.t) (ancestors_regions : T.RegionId.Set.t)
-    (v : V.typed_value) (ty : T.rty) : V.typed_avalue =
+let rec apply_proj_borrows (check_symbolic_no_ended : bool) (ctx : eval_ctx)
+    (fresh_reborrow : BorrowId.id -> BorrowId.id) (regions : RegionId.Set.t)
+    (ancestors_regions : RegionId.Set.t) (v : typed_value) (ty : rty) :
+    typed_avalue =
   (* Sanity check - TODO: move this elsewhere (here we perform the check at every
    * recursive call which is a bit overkill...) *)
   let ety = Substitute.erase_regions ty in
-  assert (ety = v.V.ty);
+  assert (ty_is_rty ty && ety = v.ty);
   (* Project - if there are no regions from the abstraction in the type, return [_] *)
-  if not (ty_has_regions_in_set regions ty) then { V.value = V.AIgnored; ty }
+  if not (ty_has_regions_in_set regions ty) then { value = AIgnored; ty }
   else
-    let value : V.avalue =
-      match (v.V.value, ty) with
-      | V.Literal _, T.Literal _ -> V.AIgnored
-      | V.Adt adt, T.Adt (id, generics) ->
+    let value : avalue =
+      match (v.value, ty) with
+      | VLiteral _, TLiteral _ -> AIgnored
+      | VAdt adt, TAdt (id, generics) ->
           (* Retrieve the types of the fields *)
           let field_types =
             Assoc.ctx_adt_value_get_inst_norm_field_rtypes ctx adt id generics
           in
           (* Project over the field values *)
-          let fields_types = List.combine adt.V.field_values field_types in
+          let fields_types = List.combine adt.field_values field_types in
           let proj_fields =
             List.map
               (fun (fv, fty) ->
@@ -118,9 +115,9 @@ let rec apply_proj_borrows (check_symbolic_no_ended : bool) (ctx : C.eval_ctx)
                   regions ancestors_regions fv fty)
               fields_types
           in
-          V.AAdt { V.variant_id = adt.V.variant_id; field_values = proj_fields }
-      | V.Bottom, _ -> raise (Failure "Unreachable")
-      | V.Borrow bc, T.Ref (r, ref_ty, kind) ->
+          AAdt { variant_id = adt.variant_id; field_values = proj_fields }
+      | VBottom, _ -> raise (Failure "Unreachable")
+      | VBorrow bc, TRef (r, ref_ty, kind) ->
           if
             (* Check if the region is in the set of projected regions (note that
              * we never project over static regions) *)
@@ -129,14 +126,14 @@ let rec apply_proj_borrows (check_symbolic_no_ended : bool) (ctx : C.eval_ctx)
             (* In the set *)
             let bc =
               match (bc, kind) with
-              | V.MutBorrow (bid, bv), T.Mut ->
+              | VMutBorrow (bid, bv), RMut ->
                   (* Apply the projection on the borrowed value *)
                   let bv =
                     apply_proj_borrows check_symbolic_no_ended ctx
                       fresh_reborrow regions ancestors_regions bv ref_ty
                   in
-                  V.AMutBorrow (bid, bv)
-              | V.SharedBorrow bid, T.Shared ->
+                  AMutBorrow (bid, bv)
+              | VSharedBorrow bid, RShared ->
                   (* Rem.: we don't need to also apply the projection on the
                      borrowed value, because for as long as the abstraction
                      lives then the shared borrow lives, which means that the
@@ -148,22 +145,22 @@ let rec apply_proj_borrows (check_symbolic_no_ended : bool) (ctx : C.eval_ctx)
                      need to lookup the shared value and project it (see the
                      other branch of the [if then else]).
                   *)
-                  V.ASharedBorrow bid
-              | V.ReservedMutBorrow _, _ ->
+                  ASharedBorrow bid
+              | VReservedMutBorrow _, _ ->
                   raise
                     (Failure
                        "Can't apply a proj_borrow over a reserved mutable \
                         borrow")
               | _ -> raise (Failure "Unreachable")
             in
-            V.ABorrow bc
+            ABorrow bc
           else
             (* Not in the set: ignore the borrow, but project the borrowed
                value (maybe some borrows *inside* the borrowed value are in
                the region set) *)
             let bc =
               match (bc, kind) with
-              | V.MutBorrow (bid, bv), T.Mut ->
+              | VMutBorrow (bid, bv), RMut ->
                   (* Apply the projection on the borrowed value *)
                   let bv =
                     apply_proj_borrows check_symbolic_no_ended ctx
@@ -175,81 +172,81 @@ let rec apply_proj_borrows (check_symbolic_no_ended : bool) (ctx : C.eval_ctx)
                     if region_in_set r ancestors_regions then Some bid else None
                   in
                   (* Return *)
-                  V.AIgnoredMutBorrow (opt_bid, bv)
-              | V.SharedBorrow bid, T.Shared ->
+                  AIgnoredMutBorrow (opt_bid, bv)
+              | VSharedBorrow bid, RShared ->
                   (* Lookup the shared value *)
                   let ek = ek_all in
                   let sv = lookup_loan ek bid ctx in
                   let asb =
                     match sv with
-                    | _, Concrete (V.SharedLoan (_, sv))
-                    | _, Abstract (V.ASharedLoan (_, sv, _)) ->
+                    | _, Concrete (VSharedLoan (_, sv))
+                    | _, Abstract (ASharedLoan (_, sv, _)) ->
                         apply_proj_borrows_on_shared_borrow ctx fresh_reborrow
                           regions sv ref_ty
                     | _ -> raise (Failure "Unexpected")
                   in
-                  V.AProjSharedBorrow asb
-              | V.ReservedMutBorrow _, _ ->
+                  AProjSharedBorrow asb
+              | VReservedMutBorrow _, _ ->
                   raise
                     (Failure
                        "Can't apply a proj_borrow over a reserved mutable \
                         borrow")
               | _ -> raise (Failure "Unreachable")
             in
-            V.ABorrow bc
-      | V.Loan _, _ -> raise (Failure "Unreachable")
-      | V.Symbolic s, _ ->
+            ABorrow bc
+      | VLoan _, _ -> raise (Failure "Unreachable")
+      | VSymbolic s, _ ->
           (* Check that the projection doesn't contain already ended regions,
            * if necessary *)
           if check_symbolic_no_ended then (
-            let ty1 = s.V.sv_ty in
+            let ty1 = s.sv_ty in
             let rset1 = ctx.ended_regions in
             let ty2 = ty in
             let rset2 = regions in
             log#ldebug
               (lazy
-                ("projections_intersect:" ^ "\n- ty1: " ^ rty_to_string ctx ty1
+                ("projections_intersect:" ^ "\n- ty1: " ^ ty_to_string ctx ty1
                ^ "\n- rset1: "
-                ^ T.RegionId.Set.to_string None rset1
-                ^ "\n- ty2: " ^ rty_to_string ctx ty2 ^ "\n- rset2: "
-                ^ T.RegionId.Set.to_string None rset2
+                ^ RegionId.Set.to_string None rset1
+                ^ "\n- ty2: " ^ ty_to_string ctx ty2 ^ "\n- rset2: "
+                ^ RegionId.Set.to_string None rset2
                 ^ "\n"));
             assert (not (projections_intersect ty1 rset1 ty2 rset2)));
-          V.ASymbolic (V.AProjBorrows (s, ty))
+          ASymbolic (AProjBorrows (s, ty))
       | _ ->
           log#lerror
             (lazy
               ("apply_proj_borrows: unexpected inputs:\n- input value: "
               ^ typed_value_to_string ctx v
-              ^ "\n- proj rty: " ^ rty_to_string ctx ty));
+              ^ "\n- proj rty: " ^ ty_to_string ctx ty));
           raise (Failure "Unreachable")
     in
-    { V.value; V.ty }
+    { value; ty }
 
-let symbolic_expansion_non_borrow_to_value (sv : V.symbolic_value)
-    (see : V.symbolic_expansion) : V.typed_value =
-  let ty = Subst.erase_regions sv.V.sv_ty in
+let symbolic_expansion_non_borrow_to_value (sv : symbolic_value)
+    (see : symbolic_expansion) : typed_value =
+  let ty = Subst.erase_regions sv.sv_ty in
   let value =
     match see with
-    | SeLiteral cv -> V.Literal cv
+    | SeLiteral cv -> VLiteral cv
     | SeAdt (variant_id, field_values) ->
         let field_values =
           List.map mk_typed_value_from_symbolic_value field_values
         in
-        V.Adt { V.variant_id; V.field_values }
+        VAdt { variant_id; field_values }
     | SeMutRef (_, _) | SeSharedRef (_, _) ->
         raise (Failure "Unexpected symbolic reference expansion")
   in
-  { V.value; V.ty }
+  { value; ty }
 
-let symbolic_expansion_non_shared_borrow_to_value (sv : V.symbolic_value)
-    (see : V.symbolic_expansion) : V.typed_value =
+let symbolic_expansion_non_shared_borrow_to_value (sv : symbolic_value)
+    (see : symbolic_expansion) : typed_value =
   match see with
   | SeMutRef (bid, bv) ->
-      let ty = Subst.erase_regions sv.V.sv_ty in
+      let ty = Subst.erase_regions sv.sv_ty in
       let bv = mk_typed_value_from_symbolic_value bv in
-      let value = V.Borrow (V.MutBorrow (bid, bv)) in
-      { V.value; ty }
+      let value = VBorrow (VMutBorrow (bid, bv)) in
+      { value; ty }
   | SeSharedRef (_, _) ->
       raise (Failure "Unexpected symbolic shared reference expansion")
   | _ -> symbolic_expansion_non_borrow_to_value sv see
@@ -258,34 +255,34 @@ let symbolic_expansion_non_shared_borrow_to_value (sv : V.symbolic_value)
 
     TODO: detailed comments. See [apply_proj_borrows]
 *)
-let apply_proj_loans_on_symbolic_expansion (regions : T.RegionId.Set.t)
-    (ancestors_regions : T.RegionId.Set.t) (see : V.symbolic_expansion)
-    (original_sv_ty : T.rty) : V.typed_avalue =
+let apply_proj_loans_on_symbolic_expansion (regions : RegionId.Set.t)
+    (ancestors_regions : RegionId.Set.t) (see : symbolic_expansion)
+    (original_sv_ty : rty) : typed_avalue =
   (* Sanity check: if we have a proj_loans over a symbolic value, it should
    * contain regions which we will project *)
   assert (ty_has_regions_in_set regions original_sv_ty);
   (* Match *)
-  let (value, ty) : V.avalue * T.rty =
+  let (value, ty) : avalue * ty =
     match (see, original_sv_ty) with
-    | SeLiteral _, T.Literal _ -> (V.AIgnored, original_sv_ty)
-    | SeAdt (variant_id, field_values), T.Adt (_id, _generics) ->
+    | SeLiteral _, TLiteral _ -> (AIgnored, original_sv_ty)
+    | SeAdt (variant_id, field_values), TAdt (_id, _generics) ->
         (* Project over the field values *)
         let field_values =
           List.map
             (mk_aproj_loans_value_from_symbolic_value regions)
             field_values
         in
-        (V.AAdt { V.variant_id; field_values }, original_sv_ty)
-    | SeMutRef (bid, spc), T.Ref (r, ref_ty, T.Mut) ->
+        (AAdt { variant_id; field_values }, original_sv_ty)
+    | SeMutRef (bid, spc), TRef (r, ref_ty, RMut) ->
         (* Sanity check *)
-        assert (spc.V.sv_ty = ref_ty);
+        assert (spc.sv_ty = ref_ty);
         (* Apply the projector to the borrowed value *)
         let child_av = mk_aproj_loans_value_from_symbolic_value regions spc in
         (* Check if the region is in the set of projected regions (note that
          * we never project over static regions) *)
         if region_in_set r regions then
           (* In the set: keep *)
-          (V.ALoan (V.AMutLoan (bid, child_av)), ref_ty)
+          (ALoan (AMutLoan (bid, child_av)), ref_ty)
         else
           (* Not in the set: ignore *)
           (* If the borrow id is in the ancestor's regions, we still need
@@ -293,10 +290,10 @@ let apply_proj_loans_on_symbolic_expansion (regions : T.RegionId.Set.t)
           let opt_bid =
             if region_in_set r ancestors_regions then Some bid else None
           in
-          (V.ALoan (V.AIgnoredMutLoan (opt_bid, child_av)), ref_ty)
-    | SeSharedRef (bids, spc), T.Ref (r, ref_ty, T.Shared) ->
+          (ALoan (AIgnoredMutLoan (opt_bid, child_av)), ref_ty)
+    | SeSharedRef (bids, spc), TRef (r, ref_ty, RShared) ->
         (* Sanity check *)
-        assert (spc.V.sv_ty = ref_ty);
+        assert (spc.sv_ty = ref_ty);
         (* Apply the projector to the borrowed value *)
         let child_av = mk_aproj_loans_value_from_symbolic_value regions spc in
         (* Check if the region is in the set of projected regions (note that
@@ -304,13 +301,13 @@ let apply_proj_loans_on_symbolic_expansion (regions : T.RegionId.Set.t)
         if region_in_set r regions then
           (* In the set: keep *)
           let shared_value = mk_typed_value_from_symbolic_value spc in
-          (V.ALoan (V.ASharedLoan (bids, shared_value, child_av)), ref_ty)
+          (ALoan (ASharedLoan (bids, shared_value, child_av)), ref_ty)
         else
           (* Not in the set: ignore *)
-          (V.ALoan (V.AIgnoredSharedLoan child_av), ref_ty)
+          (ALoan (AIgnoredSharedLoan child_av), ref_ty)
     | _ -> raise (Failure "Unreachable")
   in
-  { V.value; V.ty }
+  { value; ty }
 
 (** Auxiliary function. See [give_back_value].
 
@@ -334,8 +331,8 @@ let apply_proj_loans_on_symbolic_expansion (regions : T.RegionId.Set.t)
     borrows - easy - and mutable borrows - in this case, we reborrow the whole
     borrow: [mut_borrow ... ~~> shared_loan {...} (mut_borrow ...)]).
 *)
-let apply_reborrows (reborrows : (V.BorrowId.id * V.BorrowId.id) list)
-    (ctx : C.eval_ctx) : C.eval_ctx =
+let apply_reborrows (reborrows : (BorrowId.id * BorrowId.id) list)
+    (ctx : eval_ctx) : eval_ctx =
   (* This is a bit brutal, but whenever we insert a reborrow, we remove
    * it from the list. This allows us to check that all the reborrows were
    * applied before returning.
@@ -344,12 +341,12 @@ let apply_reborrows (reborrows : (V.BorrowId.id * V.BorrowId.id) list)
 
   (* Check if a value is a mutable borrow, and return its identifier if
      it is the case *)
-  let get_borrow_in_mut_borrow (v : V.typed_value) : V.BorrowId.id option =
-    match v.V.value with
-    | V.Borrow lc -> (
+  let get_borrow_in_mut_borrow (v : typed_value) : BorrowId.id option =
+    match v.value with
+    | VBorrow lc -> (
         match lc with
-        | V.SharedBorrow _ | V.ReservedMutBorrow _ -> None
-        | V.MutBorrow (id, _) -> Some id)
+        | VSharedBorrow _ | VReservedMutBorrow _ -> None
+        | VMutBorrow (id, _) -> Some id)
     | _ -> None
   in
 
@@ -357,12 +354,12 @@ let apply_reborrows (reborrows : (V.BorrowId.id * V.BorrowId.id) list)
   let insert_reborrows bids =
     (* Find the reborrows to apply *)
     let insert, reborrows' =
-      List.partition (fun (bid, _) -> V.BorrowId.Set.mem bid bids) !reborrows
+      List.partition (fun (bid, _) -> BorrowId.Set.mem bid bids) !reborrows
     in
     reborrows := reborrows';
     let insert = List.map snd insert in
     (* Insert the borrows *)
-    List.fold_left (fun bids bid -> V.BorrowId.Set.add bid bids) bids insert
+    List.fold_left (fun bids bid -> BorrowId.Set.add bid bids) bids insert
   in
 
   (* Get the list of reborrows for a given borrow id *)
@@ -377,8 +374,8 @@ let apply_reborrows (reborrows : (V.BorrowId.id * V.BorrowId.id) list)
 
   let borrows_to_set bids =
     List.fold_left
-      (fun bids bid -> V.BorrowId.Set.add bid bids)
-      V.BorrowId.Set.empty bids
+      (fun bids bid -> BorrowId.Set.add bid bids)
+      BorrowId.Set.empty bids
   in
 
   (* Insert reborrows for a given borrow id into a given set of borrows *)
@@ -386,36 +383,36 @@ let apply_reborrows (reborrows : (V.BorrowId.id * V.BorrowId.id) list)
     (* Find the reborrows to apply *)
     let insert = get_reborrows_for_bid bid in
     (* Insert the borrows *)
-    List.fold_left (fun bids bid -> V.BorrowId.Set.add bid bids) bids insert
+    List.fold_left (fun bids bid -> BorrowId.Set.add bid bids) bids insert
   in
 
   let obj =
     object
-      inherit [_] C.map_eval_ctx as super
+      inherit [_] map_eval_ctx as super
 
       (** We may need to reborrow mutable borrows. Note that this doesn't
           happen for aborrows *)
       method! visit_typed_value env v =
-        match v.V.value with
-        | V.Borrow (V.MutBorrow (bid, bv)) ->
+        match v.value with
+        | VBorrow (VMutBorrow (bid, bv)) ->
             let insert = get_reborrows_for_bid bid in
-            let nbc = super#visit_MutBorrow env bid bv in
-            let nbc = { v with V.value = V.Borrow nbc } in
+            let nbc = super#visit_VMutBorrow env bid bv in
+            let nbc = { v with value = VBorrow nbc } in
             if insert = [] then (* No reborrows: do nothing special *)
               nbc
             else
               (* There are reborrows: insert a shared loan *)
               let insert = borrows_to_set insert in
-              let value = V.Loan (V.SharedLoan (insert, nbc)) in
-              let ty = v.V.ty in
-              { V.value; ty }
+              let value = VLoan (VSharedLoan (insert, nbc)) in
+              let ty = v.ty in
+              { value; ty }
         | _ -> super#visit_typed_value env v
 
       (** We reimplement {!visit_loan_content} (rather than one of the sub-
           functions) on purpose: exhaustive matches are good for maintenance *)
       method! visit_loan_content env lc =
         match lc with
-        | V.SharedLoan (bids, sv) ->
+        | VSharedLoan (bids, sv) ->
             (* Insert the reborrows *)
             let bids = insert_reborrows bids in
             (* Check if the contained value is a mutable borrow, in which
@@ -431,14 +428,14 @@ let apply_reborrows (reborrows : (V.BorrowId.id * V.BorrowId.id) list)
               | Some bid -> insert_reborrows_for_bid bids bid
             in
             (* Update and explore *)
-            super#visit_SharedLoan env bids sv
-        | V.MutLoan bid ->
+            super#visit_VSharedLoan env bids sv
+        | VMutLoan bid ->
             (* Nothing special to do *)
-            super#visit_MutLoan env bid
+            super#visit_VMutLoan env bid
 
       method! visit_aloan_content env lc =
         match lc with
-        | V.ASharedLoan (bids, sv, av) ->
+        | ASharedLoan (bids, sv, av) ->
             (* Insert the reborrows *)
             let bids = insert_reborrows bids in
             (* Similarly to the non-abstraction case: check if the shared
@@ -451,12 +448,12 @@ let apply_reborrows (reborrows : (V.BorrowId.id * V.BorrowId.id) list)
             in
             (* Update and explore *)
             super#visit_ASharedLoan env bids sv av
-        | V.AIgnoredSharedLoan _
-        | V.AMutLoan (_, _)
-        | V.AEndedMutLoan { given_back = _; child = _; given_back_meta = _ }
-        | V.AEndedSharedLoan (_, _)
-        | V.AIgnoredMutLoan (_, _)
-        | V.AEndedIgnoredMutLoan
+        | AIgnoredSharedLoan _
+        | AMutLoan (_, _)
+        | AEndedMutLoan { given_back = _; child = _; given_back_meta = _ }
+        | AEndedSharedLoan (_, _)
+        | AIgnoredMutLoan (_, _)
+        | AEndedIgnoredMutLoan
             { given_back = _; child = _; given_back_meta = _ } ->
             (* Nothing particular to do *)
             super#visit_aloan_content env lc
@@ -470,32 +467,34 @@ let apply_reborrows (reborrows : (V.BorrowId.id * V.BorrowId.id) list)
   (* Return *)
   ctx
 
-let prepare_reborrows (config : C.config) (allow_reborrows : bool) :
-    (V.BorrowId.id -> V.BorrowId.id) * (C.eval_ctx -> C.eval_ctx) =
-  let reborrows : (V.BorrowId.id * V.BorrowId.id) list ref = ref [] in
+let prepare_reborrows (config : config) (allow_reborrows : bool) :
+    (BorrowId.id -> BorrowId.id) * (eval_ctx -> eval_ctx) =
+  let reborrows : (BorrowId.id * BorrowId.id) list ref = ref [] in
   (* The function to generate and register fresh reborrows *)
-  let fresh_reborrow (bid : V.BorrowId.id) : V.BorrowId.id =
+  let fresh_reborrow (bid : BorrowId.id) : BorrowId.id =
     if allow_reborrows then (
-      let bid' = C.fresh_borrow_id () in
+      let bid' = fresh_borrow_id () in
       reborrows := (bid, bid') :: !reborrows;
       bid')
     else raise (Failure "Unexpected reborrow")
   in
   (* The function to apply the reborrows in a context *)
-  let apply_registered_reborrows (ctx : C.eval_ctx) : C.eval_ctx =
-    match config.C.mode with
-    | C.ConcreteMode ->
+  let apply_registered_reborrows (ctx : eval_ctx) : eval_ctx =
+    match config.mode with
+    | ConcreteMode ->
         assert (!reborrows = []);
         ctx
-    | C.SymbolicMode ->
+    | SymbolicMode ->
         (* Apply the reborrows *)
         apply_reborrows !reborrows ctx
   in
   (fresh_reborrow, apply_registered_reborrows)
 
-let apply_proj_borrows_on_input_value (config : C.config) (ctx : C.eval_ctx)
-    (regions : T.RegionId.Set.t) (ancestors_regions : T.RegionId.Set.t)
-    (v : V.typed_value) (ty : T.rty) : C.eval_ctx * V.typed_avalue =
+(** [ty] shouldn't have erased regions *)
+let apply_proj_borrows_on_input_value (config : config) (ctx : eval_ctx)
+    (regions : RegionId.Set.t) (ancestors_regions : RegionId.Set.t)
+    (v : typed_value) (ty : rty) : eval_ctx * typed_avalue =
+  assert (ty_is_rty ty);
   let check_symbolic_no_ended = true in
   let allow_reborrows = true in
   (* Prepare the reborrows *)
diff --git a/compiler/InterpreterProjectors.mli b/compiler/InterpreterProjectors.mli
index bcc3dee2..583c6907 100644
--- a/compiler/InterpreterProjectors.mli
+++ b/compiler/InterpreterProjectors.mli
@@ -1,33 +1,25 @@
-module T = Types
-module V = Values
-module E = Expressions
-module C = Contexts
-module Subst = Substitute
-module L = Logging
-open InterpreterBorrowsCore
+open Types
+open Values
+open Contexts
 
 (** Auxiliary function.
 
     Apply a proj_borrows on a shared borrow.
     Note that when projecting over shared values, we generate
-    {!type:V.abstract_shared_borrows}, not {!type:V.avalue}s.
+    {!type:abstract_shared_borrows}, not {!type:avalue}s.
 
     Parameters:
     [regions]
     [ancestor_regions]
     [see]
-    [original_sv_ty]
+    [original_sv_ty]: shouldn't have erased regions
 *)
 val apply_proj_loans_on_symbolic_expansion :
-  T.RegionId.Set.t ->
-  T.RegionId.Set.t ->
-  V.symbolic_expansion ->
-  T.rty ->
-  V.typed_avalue
+  RegionId.Set.t -> RegionId.Set.t -> symbolic_expansion -> rty -> typed_avalue
 
 (** Convert a symbolic expansion *which is not a borrow* to a value *)
 val symbolic_expansion_non_borrow_to_value :
-  V.symbolic_value -> V.symbolic_expansion -> V.typed_value
+  symbolic_value -> symbolic_expansion -> typed_value
 
 (** Convert a symbolic expansion *which is not a shared borrow* to a value.
 
@@ -36,7 +28,7 @@ val symbolic_expansion_non_borrow_to_value :
     during a symbolic expansion.
   *)
 val symbolic_expansion_non_shared_borrow_to_value :
-  V.symbolic_value -> V.symbolic_expansion -> V.typed_value
+  symbolic_value -> symbolic_expansion -> typed_value
 
 (** Auxiliary function to prepare reborrowing operations (used when
     applying projectors).
@@ -51,9 +43,7 @@ val symbolic_expansion_non_shared_borrow_to_value :
     - [allow_reborrows]
  *)
 val prepare_reborrows :
-  C.config ->
-  bool ->
-  (V.BorrowId.id -> V.BorrowId.id) * (C.eval_ctx -> C.eval_ctx)
+  config -> bool -> (BorrowId.id -> BorrowId.id) * (eval_ctx -> eval_ctx)
 
 (** Apply (and reduce) a projector over borrows to an avalue.
     We use this for instance to spread the borrows present in the inputs
@@ -107,13 +97,13 @@ val prepare_reborrows :
 *)
 val apply_proj_borrows :
   bool ->
-  C.eval_ctx ->
-  (V.BorrowId.id -> V.BorrowId.id) ->
-  T.RegionId.Set.t ->
-  T.RegionId.Set.t ->
-  V.typed_value ->
-  T.rty ->
-  V.typed_avalue
+  eval_ctx ->
+  (BorrowId.id -> BorrowId.id) ->
+  RegionId.Set.t ->
+  RegionId.Set.t ->
+  typed_value ->
+  rty ->
+  typed_avalue
 
 (** Parameters:
     - [config]
@@ -121,14 +111,14 @@ val apply_proj_borrows :
     - [regions]: the regions to project
     - [ancestors_regions]
     - [v]: the value on which to apply the projection
-    - [ty]: the type (with regions) to use for the projection
-
+    - [ty]: the type (with regions) to use for the projection (shouldn't have
+      erased regions)
  *)
 val apply_proj_borrows_on_input_value :
-  C.config ->
-  C.eval_ctx ->
-  T.RegionId.Set.t ->
-  T.RegionId.Set.t ->
-  V.typed_value ->
-  T.rty ->
-  C.eval_ctx * V.typed_avalue
+  config ->
+  eval_ctx ->
+  RegionId.Set.t ->
+  RegionId.Set.t ->
+  typed_value ->
+  rty ->
+  eval_ctx * typed_avalue
diff --git a/compiler/InterpreterStatements.ml b/compiler/InterpreterStatements.ml
index e0c4703b..9ea5387f 100644
--- a/compiler/InterpreterStatements.ml
+++ b/compiler/InterpreterStatements.ml
@@ -1,28 +1,24 @@
-module T = Types
-module PV = PrimitiveValues
-module V = Values
-module E = Expressions
-module C = Contexts
-module Subst = Substitute
-module A = LlbcAst
-module L = Logging
+open Types
 open TypesUtils
+open Values
 open ValuesUtils
-module Inv = Invariants
-module S = SynthesizeSymbolic
+open Expressions
+open Contexts
+open LlbcAst
 open Cps
 open InterpreterUtils
 open InterpreterProjectors
 open InterpreterExpansion
 open InterpreterPaths
 open InterpreterExpressions
-module PCtx = Print.EvalCtxLlbcAst
+module Subst = Substitute
+module S = SynthesizeSymbolic
 
 (** The local logger *)
 let log = L.statements_log
 
 (** Drop a value at a given place - TODO: factorize this with [assign_to_place] *)
-let drop_value (config : C.config) (p : E.place) : cm_fun =
+let drop_value (config : config) (p : place) : cm_fun =
  fun cf ctx ->
   log#ldebug
     (lazy
@@ -36,14 +32,14 @@ let drop_value (config : C.config) (p : E.place) : cm_fun =
   (* Prepare the place (by ending the outer loans *at* the place). *)
   let cc = comp cc (prepare_lplace config p) in
   (* Replace the value with {!Bottom} *)
-  let replace cf (v : V.typed_value) ctx =
+  let replace cf (v : typed_value) ctx =
     (* Move the value at destination (that we will overwrite) to a dummy variable
      * to preserve the borrows it may contain *)
     let mv = InterpreterPaths.read_place access p ctx in
-    let dummy_id = C.fresh_dummy_var_id () in
-    let ctx = C.ctx_push_dummy_var ctx dummy_id mv in
+    let dummy_id = fresh_dummy_var_id () in
+    let ctx = ctx_push_dummy_var ctx dummy_id mv in
     (* Update the destination to ⊥ *)
-    let nv = { v with value = V.Bottom } in
+    let nv = { v with value = VBottom } in
     let ctx = write_place access p nv ctx in
     log#ldebug
       (lazy
@@ -55,40 +51,39 @@ let drop_value (config : C.config) (p : E.place) : cm_fun =
   comp cc replace cf ctx
 
 (** Push a dummy variable to the environment *)
-let push_dummy_var (vid : C.DummyVarId.id) (v : V.typed_value) : cm_fun =
+let push_dummy_var (vid : DummyVarId.id) (v : typed_value) : cm_fun =
  fun cf ctx ->
-  let ctx = C.ctx_push_dummy_var ctx vid v in
+  let ctx = ctx_push_dummy_var ctx vid v in
   cf ctx
 
 (** Remove a dummy variable from the environment *)
-let remove_dummy_var (vid : C.DummyVarId.id) (cf : V.typed_value -> m_fun) :
-    m_fun =
+let remove_dummy_var (vid : DummyVarId.id) (cf : typed_value -> m_fun) : m_fun =
  fun ctx ->
-  let ctx, v = C.ctx_remove_dummy_var ctx vid in
+  let ctx, v = ctx_remove_dummy_var ctx vid in
   cf v ctx
 
 (** Push an uninitialized variable to the environment *)
-let push_uninitialized_var (var : A.var) : cm_fun =
+let push_uninitialized_var (var : var) : cm_fun =
  fun cf ctx ->
-  let ctx = C.ctx_push_uninitialized_var ctx var in
+  let ctx = ctx_push_uninitialized_var ctx var in
   cf ctx
 
 (** Push a list of uninitialized variables to the environment *)
-let push_uninitialized_vars (vars : A.var list) : cm_fun =
+let push_uninitialized_vars (vars : var list) : cm_fun =
  fun cf ctx ->
-  let ctx = C.ctx_push_uninitialized_vars ctx vars in
+  let ctx = ctx_push_uninitialized_vars ctx vars in
   cf ctx
 
 (** Push a variable to the environment *)
-let push_var (var : A.var) (v : V.typed_value) : cm_fun =
+let push_var (var : var) (v : typed_value) : cm_fun =
  fun cf ctx ->
-  let ctx = C.ctx_push_var ctx var v in
+  let ctx = ctx_push_var ctx var v in
   cf ctx
 
 (** Push a list of variables to the environment *)
-let push_vars (vars : (A.var * V.typed_value) list) : cm_fun =
+let push_vars (vars : (var * typed_value) list) : cm_fun =
  fun cf ctx ->
-  let ctx = C.ctx_push_vars ctx vars in
+  let ctx = ctx_push_vars ctx vars in
   cf ctx
 
 (** Assign a value to a given place.
@@ -98,8 +93,7 @@ let push_vars (vars : (A.var * V.typed_value) list) : cm_fun =
     dummy variable and putting in its destination (after having checked that
     preparing the destination didn't introduce ⊥).
  *)
-let assign_to_place (config : C.config) (rv : V.typed_value) (p : E.place) :
-    cm_fun =
+let assign_to_place (config : config) (rv : typed_value) (p : place) : cm_fun =
  fun cf ctx ->
   log#ldebug
     (lazy
@@ -108,20 +102,20 @@ let assign_to_place (config : C.config) (rv : V.typed_value) (p : E.place) :
       ^ "\n- p: " ^ place_to_string ctx p ^ "\n- Initial context:\n"
       ^ eval_ctx_to_string ctx));
   (* Push the rvalue to a dummy variable, for bookkeeping *)
-  let rvalue_vid = C.fresh_dummy_var_id () in
+  let rvalue_vid = fresh_dummy_var_id () in
   let cc = push_dummy_var rvalue_vid rv in
   (* Prepare the destination *)
   let cc = comp cc (prepare_lplace config p) in
   (* Retrieve the rvalue from the dummy variable *)
   let cc = comp cc (fun cf _lv -> remove_dummy_var rvalue_vid cf) in
   (* Update the destination *)
-  let move_dest cf (rv : V.typed_value) : m_fun =
+  let move_dest cf (rv : typed_value) : m_fun =
    fun ctx ->
     (* Move the value at destination (that we will overwrite) to a dummy variable
      * to preserve the borrows *)
     let mv = InterpreterPaths.read_place Write p ctx in
-    let dest_vid = C.fresh_dummy_var_id () in
-    let ctx = C.ctx_push_dummy_var ctx dest_vid mv in
+    let dest_vid = fresh_dummy_var_id () in
+    let ctx = ctx_push_dummy_var ctx dest_vid mv in
     (* Write to the destination *)
     (* Checks - maybe the bookkeeping updated the rvalue and introduced bottoms *)
     assert (not (bottom_in_value ctx.ended_regions rv));
@@ -141,15 +135,15 @@ let assign_to_place (config : C.config) (rv : V.typed_value) (p : E.place) :
   comp cc move_dest cf ctx
 
 (** Evaluate an assertion, when the scrutinee is not symbolic *)
-let eval_assertion_concrete (config : C.config) (assertion : A.assertion) :
+let eval_assertion_concrete (config : config) (assertion : assertion) :
     st_cm_fun =
  fun cf ctx ->
   (* There won't be any symbolic expansions: fully evaluate the operand *)
   let eval_op = eval_operand config assertion.cond in
-  let eval_assert cf (v : V.typed_value) : m_fun =
+  let eval_assert cf (v : typed_value) : m_fun =
    fun ctx ->
     match v.value with
-    | Literal (Bool b) ->
+    | VLiteral (VBool b) ->
         (* Branch *)
         if b = assertion.expected then cf Unit ctx else cf Panic ctx
     | _ ->
@@ -165,33 +159,33 @@ let eval_assertion_concrete (config : C.config) (assertion : A.assertion) :
     a call to [assert ...] then continue in the success branch (and thus
     expand the boolean to [true]).
  *)
-let eval_assertion (config : C.config) (assertion : A.assertion) : st_cm_fun =
+let eval_assertion (config : config) (assertion : assertion) : st_cm_fun =
  fun cf ctx ->
   (* Evaluate the operand *)
   let eval_op = eval_operand config assertion.cond in
   (* Evaluate the assertion *)
-  let eval_assert cf (v : V.typed_value) : m_fun =
+  let eval_assert cf (v : typed_value) : m_fun =
    fun ctx ->
-    assert (v.ty = T.Literal PV.Bool);
+    assert (v.ty = TLiteral TBool);
     (* We make a choice here: we could completely decouple the concrete and
      * symbolic executions here but choose not to. In the case where we
      * know the concrete value of the boolean we test, we use this value
      * even if we are in symbolic mode. Note that this case should be
      * extremely rare... *)
     match v.value with
-    | Literal (Bool _) ->
+    | VLiteral (VBool _) ->
         (* Delegate to the concrete evaluation function *)
         eval_assertion_concrete config assertion cf ctx
-    | Symbolic sv ->
-        assert (config.mode = C.SymbolicMode);
-        assert (sv.V.sv_ty = T.Literal PV.Bool);
+    | VSymbolic sv ->
+        assert (config.mode = SymbolicMode);
+        assert (sv.sv_ty = TLiteral TBool);
         (* We continue the execution as if the test had succeeded, and thus
          * perform the symbolic expansion: sv ~~> true.
          * We will of course synthesize an assertion in the generated code
          * (see below). *)
         let ctx =
-          apply_symbolic_expansion_non_borrow config sv
-            (V.SeLiteral (PV.Bool true)) ctx
+          apply_symbolic_expansion_non_borrow config sv (SeLiteral (VBool true))
+            ctx
         in
         (* Continue *)
         let expr = cf Unit ctx in
@@ -210,29 +204,29 @@ let eval_assertion (config : C.config) (assertion : A.assertion) : st_cm_fun =
     - either the discriminant is already the proper one (in which case we
       don't do anything)
     - or it is not the proper one (because the variant is not the proper
-      one, or the value is actually {!V.Bottom} - this happens when
+      one, or the value is actually {!Bottom} - this happens when
       initializing ADT values), in which case we replace the value with
-      a variant with all its fields set to {!V.Bottom}.
+      a variant with all its fields set to {!Bottom}.
       For instance, something like: [Cons Bottom Bottom].
  *)
-let set_discriminant (config : C.config) (p : E.place)
-    (variant_id : T.VariantId.id) : st_cm_fun =
+let set_discriminant (config : config) (p : place) (variant_id : VariantId.id) :
+    st_cm_fun =
  fun cf ctx ->
   log#ldebug
     (lazy
       ("set_discriminant:" ^ "\n- p: " ^ place_to_string ctx p
      ^ "\n- variant id: "
-      ^ T.VariantId.to_string variant_id
+      ^ VariantId.to_string variant_id
       ^ "\n- initial context:\n" ^ eval_ctx_to_string ctx));
   (* Access the value *)
   let access = Write in
   let cc = update_ctx_along_read_place config access p in
   let cc = comp cc (prepare_lplace config p) in
   (* Update the value *)
-  let update_value cf (v : V.typed_value) : m_fun =
+  let update_value cf (v : typed_value) : m_fun =
    fun ctx ->
-    match (v.V.ty, v.V.value) with
-    | T.Adt ((T.AdtId _ as type_id), generics), V.Adt av -> (
+    match (v.ty, v.value) with
+    | TAdt ((TAdtId _ as type_id), generics), VAdt av -> (
         (* There are two situations:
            - either the discriminant is already the proper one (in which case we
              don't do anything)
@@ -248,22 +242,22 @@ let set_discriminant (config : C.config) (p : E.place)
               (* Replace the value *)
               let bottom_v =
                 match type_id with
-                | T.AdtId def_id ->
+                | TAdtId def_id ->
                     compute_expanded_bottom_adt_value ctx def_id
                       (Some variant_id) generics
                 | _ -> raise (Failure "Unreachable")
               in
               assign_to_place config bottom_v p (cf Unit) ctx)
-    | T.Adt ((T.AdtId _ as type_id), generics), V.Bottom ->
+    | TAdt ((TAdtId _ as type_id), generics), VBottom ->
         let bottom_v =
           match type_id with
-          | T.AdtId def_id ->
+          | TAdtId def_id ->
               compute_expanded_bottom_adt_value ctx def_id (Some variant_id)
                 generics
           | _ -> raise (Failure "Unreachable")
         in
         assign_to_place config bottom_v p (cf Unit) ctx
-    | _, V.Symbolic _ ->
+    | _, VSymbolic _ ->
         assert (config.mode = SymbolicMode);
         (* This is a bit annoying: in theory we should expand the symbolic value
          * then set the discriminant, because in the case the discriminant is
@@ -273,16 +267,16 @@ let set_discriminant (config : C.config) (p : E.place)
          * setting a discriminant should only be used to initialize a value,
          * or reset an already initialized value, really. *)
         raise (Failure "Unexpected value")
-    | _, (V.Adt _ | V.Bottom) -> raise (Failure "Inconsistent state")
-    | _, (V.Literal _ | V.Borrow _ | V.Loan _) ->
+    | _, (VAdt _ | VBottom) -> raise (Failure "Inconsistent state")
+    | _, (VLiteral _ | VBorrow _ | VLoan _) ->
         raise (Failure "Unexpected value")
   in
   (* Compose and apply *)
   comp cc update_value cf ctx
 
 (** Push a frame delimiter in the context's environment *)
-let ctx_push_frame (ctx : C.eval_ctx) : C.eval_ctx =
-  { ctx with env = Frame :: ctx.env }
+let ctx_push_frame (ctx : eval_ctx) : eval_ctx =
+  { ctx with env = EFrame :: ctx.env }
 
 (** Push a frame delimiter in the context's environment *)
 let push_frame : cm_fun = fun cf ctx -> cf (ctx_push_frame ctx)
@@ -290,8 +284,8 @@ let push_frame : cm_fun = fun cf ctx -> cf (ctx_push_frame ctx)
 (** Small helper: compute the type of the return value for a specific
     instantiation of an assumed function.
  *)
-let get_assumed_function_return_type (ctx : C.eval_ctx) (fid : A.assumed_fun_id)
-    (generics : T.egeneric_args) : T.ety =
+let get_assumed_function_return_type (ctx : eval_ctx) (fid : assumed_fun_id)
+    (generics : generic_args) : ety =
   assert (generics.trait_refs = []);
   (* [Box::free] has a special treatment *)
   match fid with
@@ -305,51 +299,50 @@ let get_assumed_function_return_type (ctx : C.eval_ctx) (fid : A.assumed_fun_id)
       let sg = Assumed.get_assumed_fun_sig fid in
       (* Instantiate the return type  *)
       (* There shouldn't be any reference to Self *)
-      let tr_self : T.erased_region T.trait_instance_id =
-        T.UnknownTrait __FUNCTION__
-      in
+      let tr_self : trait_instance_id = UnknownTrait __FUNCTION__ in
+      let generics = Subst.generic_args_erase_regions generics in
       let { Subst.r_subst = _; ty_subst; cg_subst; tr_subst; tr_self } =
-        Subst.make_esubst_from_generics sg.generics generics tr_self
+        Subst.make_subst_from_generics sg.generics generics tr_self
       in
       let ty =
         Subst.erase_regions_substitute_types ty_subst cg_subst tr_subst tr_self
           sg.output
       in
-      Assoc.ctx_normalize_ety ctx ty
+      AssociatedTypes.ctx_normalize_erase_ty ctx ty
 
-let move_return_value (config : C.config) (pop_return_value : bool)
-    (cf : V.typed_value option -> m_fun) : m_fun =
+let move_return_value (config : config) (pop_return_value : bool)
+    (cf : typed_value option -> m_fun) : m_fun =
  fun ctx ->
   if pop_return_value then
-    let ret_vid = E.VarId.zero in
-    let cc = eval_operand config (E.Move (mk_place_from_var_id ret_vid)) in
+    let ret_vid = VarId.zero in
+    let cc = eval_operand config (Move (mk_place_from_var_id ret_vid)) in
     cc (fun v ctx -> cf (Some v) ctx) ctx
   else cf None ctx
 
-let pop_frame (config : C.config) (pop_return_value : bool)
-    (cf : V.typed_value option -> m_fun) : m_fun =
+let pop_frame (config : config) (pop_return_value : bool)
+    (cf : typed_value option -> m_fun) : m_fun =
  fun ctx ->
   (* Debug *)
   log#ldebug (lazy ("pop_frame:\n" ^ eval_ctx_to_string ctx));
 
   (* List the local variables, but the return variable *)
-  let ret_vid = E.VarId.zero in
+  let ret_vid = VarId.zero in
   let rec list_locals env =
     match env with
     | [] -> raise (Failure "Inconsistent environment")
-    | C.Abs _ :: env -> list_locals env
-    | C.Var (DummyBinder _, _) :: env -> list_locals env
-    | C.Var (VarBinder var, _) :: env ->
+    | EAbs _ :: env -> list_locals env
+    | EBinding (BDummy _, _) :: env -> list_locals env
+    | EBinding (BVar var, _) :: env ->
         let locals = list_locals env in
         if var.index <> ret_vid then var.index :: locals else locals
-    | C.Frame :: _ -> []
+    | EFrame :: _ -> []
   in
-  let locals : E.VarId.id list = list_locals ctx.env in
+  let locals : VarId.id list = list_locals ctx.env in
   (* Debug *)
   log#ldebug
     (lazy
       ("pop_frame: locals in which to drop the outer loans: ["
-      ^ String.concat "," (List.map E.VarId.to_string locals)
+      ^ String.concat "," (List.map VarId.to_string locals)
       ^ "]"));
 
   (* Move the return value out of the return variable *)
@@ -364,7 +357,7 @@ let pop_frame (config : C.config) (pop_return_value : bool)
   in
 
   (* Drop the outer *loans* we find in the local variables *)
-  let cf_drop_loans_in_locals cf (ret_value : V.typed_value option) : m_fun =
+  let cf_drop_loans_in_locals cf (ret_value : typed_value option) : m_fun =
     (* Drop the loans *)
     let locals = List.rev locals in
     let cf_drop =
@@ -392,13 +385,13 @@ let pop_frame (config : C.config) (pop_return_value : bool)
   let rec pop env =
     match env with
     | [] -> raise (Failure "Inconsistent environment")
-    | C.Abs abs :: env -> C.Abs abs :: pop env
-    | C.Var (_, v) :: env ->
-        let vid = C.fresh_dummy_var_id () in
-        C.Var (C.DummyBinder vid, v) :: pop env
-    | C.Frame :: env -> (* Stop here *) env
+    | EAbs abs :: env -> EAbs abs :: pop env
+    | EBinding (_, v) :: env ->
+        let vid = fresh_dummy_var_id () in
+        EBinding (BDummy vid, v) :: pop env
+    | EFrame :: env -> (* Stop here *) env
   in
-  let cf_pop cf (ret_value : V.typed_value option) : m_fun =
+  let cf_pop cf (ret_value : typed_value option) : m_fun =
    fun ctx ->
     let env = pop ctx.env in
     let ctx = { ctx with env } in
@@ -408,7 +401,7 @@ let pop_frame (config : C.config) (pop_return_value : bool)
   comp cc cf_pop cf ctx
 
 (** Pop the current frame and assign the returned value to its destination. *)
-let pop_frame_assign (config : C.config) (dest : E.place) : cm_fun =
+let pop_frame_assign (config : config) (dest : place) : cm_fun =
   let cf_pop = pop_frame config true in
   let cf_assign cf ret_value : m_fun =
     assign_to_place config (Option.get ret_value) dest cf
@@ -416,8 +409,7 @@ let pop_frame_assign (config : C.config) (dest : E.place) : cm_fun =
   comp cf_pop cf_assign
 
 (** Auxiliary function - see {!eval_assumed_function_call} *)
-let eval_box_new_concrete (config : C.config) (generics : T.egeneric_args) :
-    cm_fun =
+let eval_box_new_concrete (config : config) (generics : generic_args) : cm_fun =
  fun cf ctx ->
   (* Check and retrieve the arguments *)
   match
@@ -426,29 +418,29 @@ let eval_box_new_concrete (config : C.config) (generics : T.egeneric_args) :
   | ( [],
       [ boxed_ty ],
       [],
-      Var (VarBinder input_var, input_value)
-      :: Var (_ret_var, _)
-      :: C.Frame :: _ ) ->
+      EBinding (BVar input_var, input_value)
+      :: EBinding (_ret_var, _)
+      :: EFrame :: _ ) ->
       (* Required type checking *)
-      assert (input_value.V.ty = boxed_ty);
+      assert (input_value.ty = boxed_ty);
 
       (* Move the input value *)
       let cf_move =
-        eval_operand config (E.Move (mk_place_from_var_id input_var.C.index))
+        eval_operand config (Move (mk_place_from_var_id input_var.index))
       in
 
       (* Create the new box *)
-      let cf_create cf (moved_input_value : V.typed_value) : m_fun =
+      let cf_create cf (moved_input_value : typed_value) : m_fun =
         (* Create the box value *)
         let generics = TypesUtils.mk_generic_args_from_types [ boxed_ty ] in
-        let box_ty = T.Adt (T.Assumed T.Box, generics) in
+        let box_ty = TAdt (TAssumed TBox, generics) in
         let box_v =
-          V.Adt { variant_id = None; field_values = [ moved_input_value ] }
+          VAdt { variant_id = None; field_values = [ moved_input_value ] }
         in
         let box_v = mk_typed_value box_ty box_v in
 
         (* Move this value to the return variable *)
-        let dest = mk_place_from_var_id E.VarId.zero in
+        let dest = mk_place_from_var_id VarId.zero in
         let cf_assign = assign_to_place config box_v dest in
 
         (* Continue *)
@@ -478,14 +470,14 @@ let eval_box_new_concrete (config : C.config) (generics : T.egeneric_args) :
     It thus updates the box value (by calling {!drop_value}) and updates
     the destination (by setting it to [()]).
 *)
-let eval_box_free (config : C.config) (generics : T.egeneric_args)
-    (args : E.operand list) (dest : E.place) : cm_fun =
+let eval_box_free (config : config) (generics : generic_args)
+    (args : operand list) (dest : place) : cm_fun =
  fun cf ctx ->
   match (generics.regions, generics.types, generics.const_generics, args) with
-  | [], [ boxed_ty ], [], [ E.Move input_box_place ] ->
+  | [], [ boxed_ty ], [], [ Move input_box_place ] ->
       (* Required type checking *)
       let input_box = InterpreterPaths.read_place Write input_box_place ctx in
-      (let input_ty = ty_get_box input_box.V.ty in
+      (let input_ty = ty_get_box input_box.ty in
        assert (input_ty = boxed_ty));
 
       (* Drop the value *)
@@ -499,8 +491,8 @@ let eval_box_free (config : C.config) (generics : T.egeneric_args)
   | _ -> raise (Failure "Inconsistent state")
 
 (** Evaluate a non-local function call in concrete mode *)
-let eval_assumed_function_call_concrete (config : C.config)
-    (fid : A.assumed_fun_id) (call : A.call) : cm_fun =
+let eval_assumed_function_call_concrete (config : config) (fid : assumed_fun_id)
+    (call : call) : cm_fun =
   let generics = call.func.generics in
   let args = call.args in
   let dest = call.dest in
@@ -529,22 +521,22 @@ let eval_assumed_function_call_concrete (config : C.config)
        * below, without having to introduce an intermediary function call,
        * but it made it less clear where the computed values came from,
        * so we reversed the modifications. *)
-      let cf_eval_call cf (args_vl : V.typed_value list) : m_fun =
+      let cf_eval_call cf (args_vl : typed_value list) : m_fun =
        fun ctx ->
         (* Push the stack frame: we initialize the frame with the return variable,
            and one variable per input argument *)
         let cc = push_frame in
 
         (* Create and push the return variable *)
-        let ret_vid = E.VarId.zero in
+        let ret_vid = VarId.zero in
         let ret_ty = get_assumed_function_return_type ctx fid generics in
         let ret_var = mk_var ret_vid (Some "@return") ret_ty in
         let cc = comp cc (push_uninitialized_var ret_var) in
 
         (* Create and push the input variables *)
         let input_vars =
-          E.VarId.mapi_from1
-            (fun id (v : V.typed_value) -> (mk_var id None v.V.ty, v))
+          VarId.mapi_from1
+            (fun id (v : typed_value) -> (mk_var id None v.ty, v))
             args_vl
         in
         let cc = comp cc (push_vars input_vars) in
@@ -558,8 +550,7 @@ let eval_assumed_function_call_concrete (config : C.config)
           | BoxFree ->
               (* Should have been treated above *) raise (Failure "Unreachable")
           | ArrayIndexShared | ArrayIndexMut | ArrayToSliceShared
-          | ArrayToSliceMut | ArrayRepeat | SliceIndexShared | SliceIndexMut
-          | SliceLen ->
+          | ArrayToSliceMut | ArrayRepeat | SliceIndexShared | SliceIndexMut ->
               raise (Failure "Unimplemented")
         in
 
@@ -583,49 +574,48 @@ let eval_assumed_function_call_concrete (config : C.config)
     which can end or not.
  *)
 let create_empty_abstractions_from_abs_region_groups
-    (kind : T.RegionGroupId.id -> V.abs_kind) (rgl : A.abs_region_group list)
-    (region_can_end : T.RegionGroupId.id -> bool) : V.abs list =
+    (kind : RegionGroupId.id -> abs_kind) (rgl : abs_region_group list)
+    (region_can_end : RegionGroupId.id -> bool) : abs list =
   (* We use a reference to progressively create a map from abstraction ids
    * to set of ancestor regions. Note that {!abs_to_ancestors_regions} [abs_id]
    * returns the union of:
    * - the regions of the ancestors of abs_id
    * - the regions of abs_id
    *)
-  let abs_to_ancestors_regions : T.RegionId.Set.t V.AbstractionId.Map.t ref =
-    ref V.AbstractionId.Map.empty
+  let abs_to_ancestors_regions : RegionId.Set.t AbstractionId.Map.t ref =
+    ref AbstractionId.Map.empty
   in
   (* Auxiliary function to create one abstraction *)
-  let create_abs (rg_id : T.RegionGroupId.id) (rg : A.abs_region_group) : V.abs
-      =
-    let abs_id = rg.T.id in
+  let create_abs (rg_id : RegionGroupId.id) (rg : abs_region_group) : abs =
+    let abs_id = rg.id in
     let original_parents = rg.parents in
     let parents =
       List.fold_left
-        (fun s pid -> V.AbstractionId.Set.add pid s)
-        V.AbstractionId.Set.empty rg.parents
+        (fun s pid -> AbstractionId.Set.add pid s)
+        AbstractionId.Set.empty rg.parents
     in
     let regions =
       List.fold_left
-        (fun s rid -> T.RegionId.Set.add rid s)
-        T.RegionId.Set.empty rg.regions
+        (fun s rid -> RegionId.Set.add rid s)
+        RegionId.Set.empty rg.regions
     in
     let ancestors_regions =
       List.fold_left
         (fun acc parent_id ->
-          T.RegionId.Set.union acc
-            (V.AbstractionId.Map.find parent_id !abs_to_ancestors_regions))
-        T.RegionId.Set.empty rg.parents
+          RegionId.Set.union acc
+            (AbstractionId.Map.find parent_id !abs_to_ancestors_regions))
+        RegionId.Set.empty rg.parents
     in
     let ancestors_regions_union_current_regions =
-      T.RegionId.Set.union ancestors_regions regions
+      RegionId.Set.union ancestors_regions regions
     in
     let can_end = region_can_end rg_id in
     abs_to_ancestors_regions :=
-      V.AbstractionId.Map.add abs_id ancestors_regions_union_current_regions
+      AbstractionId.Map.add abs_id ancestors_regions_union_current_regions
         !abs_to_ancestors_regions;
     (* Create the abstraction *)
     {
-      V.abs_id;
+      abs_id;
       kind = kind rg_id;
       can_end;
       parents;
@@ -636,14 +626,13 @@ let create_empty_abstractions_from_abs_region_groups
     }
   in
   (* Apply *)
-  T.RegionGroupId.mapi create_abs rgl
+  RegionGroupId.mapi create_abs rgl
 
 let create_push_abstractions_from_abs_region_groups
-    (kind : T.RegionGroupId.id -> V.abs_kind) (rgl : A.abs_region_group list)
-    (region_can_end : T.RegionGroupId.id -> bool)
-    (compute_abs_avalues :
-      V.abs -> C.eval_ctx -> C.eval_ctx * V.typed_avalue list)
-    (ctx : C.eval_ctx) : C.eval_ctx =
+    (kind : RegionGroupId.id -> abs_kind) (rgl : abs_region_group list)
+    (region_can_end : RegionGroupId.id -> bool)
+    (compute_abs_avalues : abs -> eval_ctx -> eval_ctx * typed_avalue list)
+    (ctx : eval_ctx) : eval_ctx =
   (* Initialize the abstractions as empty (i.e., with no avalues) abstractions *)
   let empty_absl =
     create_empty_abstractions_from_abs_region_groups kind rgl region_can_end
@@ -651,20 +640,20 @@ let create_push_abstractions_from_abs_region_groups
 
   (* Compute and add the avalues to the abstractions, the insert the abstractions
    * in the context. *)
-  let insert_abs (ctx : C.eval_ctx) (abs : V.abs) : C.eval_ctx =
+  let insert_abs (ctx : eval_ctx) (abs : abs) : eval_ctx =
     (* Compute the values to insert in the abstraction *)
     let ctx, avalues = compute_abs_avalues abs ctx in
     (* Add the avalues to the abstraction *)
     let abs = { abs with avalues } in
     (* Insert the abstraction in the context *)
-    let ctx = { ctx with env = Abs abs :: ctx.env } in
+    let ctx = { ctx with env = EAbs abs :: ctx.env } in
     (* Return *)
     ctx
   in
   List.fold_left insert_abs ctx empty_absl
 
 (** Evaluate a statement *)
-let rec eval_statement (config : C.config) (st : A.statement) : st_cm_fun =
+let rec eval_statement (config : config) (st : statement) : st_cm_fun =
  fun cf ctx ->
   (* Debugging *)
   log#ldebug
@@ -677,23 +666,23 @@ let rec eval_statement (config : C.config) (st : A.statement) : st_cm_fun =
    * checking the invariants *)
   let cc = greedy_expand_symbolic_values config in
   (* Sanity check *)
-  let cc = comp cc Inv.cf_check_invariants in
+  let cc = comp cc Invariants.cf_check_invariants in
 
   (* Evaluate *)
   let cf_eval_st cf : m_fun =
    fun ctx ->
     match st.content with
-    | A.Assign (p, rvalue) -> (
+    | Assign (p, rvalue) -> (
         (* We handle global assignments separately *)
         match rvalue with
-        | E.Global gid ->
+        | Global gid ->
             (* Evaluate the global *)
             eval_global config p gid cf ctx
         | _ ->
             (* Evaluate the rvalue *)
             let cf_eval_rvalue = eval_rvalue_not_global config rvalue in
             (* Assign *)
-            let cf_assign cf (res : (V.typed_value, eval_error) result) ctx =
+            let cf_assign cf (res : (typed_value, eval_error) result) ctx =
               log#ldebug
                 (lazy
                   ("about to assign to place: " ^ place_to_string ctx p
@@ -707,11 +696,10 @@ let rec eval_statement (config : C.config) (st : A.statement) : st_cm_fun =
                    * also it can lead to issues - for instance, if we borrow a
                    * reserved borrow, we later can't translate it to pure values...) *)
                   match rvalue with
-                  | E.Global _ -> raise (Failure "Unreachable")
-                  | E.Use _
-                  | E.RvRef (_, (E.Shared | E.Mut | E.TwoPhaseMut | E.Shallow))
-                  | E.UnaryOp _ | E.BinaryOp _ | E.Discriminant _
-                  | E.Aggregate _ ->
+                  | Global _ -> raise (Failure "Unreachable")
+                  | Use _
+                  | RvRef (_, (BShared | BMut | BTwoPhaseMut | BShallow))
+                  | UnaryOp _ | BinaryOp _ | Discriminant _ | Aggregate _ ->
                       let rp = rvalue_get_place rvalue in
                       let rp =
                         match rp with
@@ -724,18 +712,18 @@ let rec eval_statement (config : C.config) (st : A.statement) : st_cm_fun =
 
             (* Compose and apply *)
             comp cf_eval_rvalue cf_assign cf ctx)
-    | A.FakeRead p -> eval_fake_read config p (cf Unit) ctx
-    | A.SetDiscriminant (p, variant_id) ->
+    | FakeRead p -> eval_fake_read config p (cf Unit) ctx
+    | SetDiscriminant (p, variant_id) ->
         set_discriminant config p variant_id cf ctx
-    | A.Drop p -> drop_value config p (cf Unit) ctx
-    | A.Assert assertion -> eval_assertion config assertion cf ctx
-    | A.Call call -> eval_function_call config call cf ctx
-    | A.Panic -> cf Panic ctx
-    | A.Return -> cf Return ctx
-    | A.Break i -> cf (Break i) ctx
-    | A.Continue i -> cf (Continue i) ctx
-    | A.Nop -> cf Unit ctx
-    | A.Sequence (st1, st2) ->
+    | Drop p -> drop_value config p (cf Unit) ctx
+    | Assert assertion -> eval_assertion config assertion cf ctx
+    | Call call -> eval_function_call config call cf ctx
+    | Panic -> cf Panic ctx
+    | Return -> cf Return ctx
+    | Break i -> cf (Break i) ctx
+    | Continue i -> cf (Continue i) ctx
+    | Nop -> cf Unit ctx
+    | Sequence (st1, st2) ->
         (* Evaluate the first statement *)
         let cf_st1 = eval_statement config st1 in
         (* Evaluate the sequence *)
@@ -750,38 +738,36 @@ let rec eval_statement (config : C.config) (st : A.statement) : st_cm_fun =
         in
         (* Compose and apply *)
         comp cf_st1 cf_st2 cf ctx
-    | A.Loop loop_body ->
-        InterpreterLoops.eval_loop config
+    | Loop loop_body ->
+        InterpreterLoops.eval_loop config st.meta
           (eval_statement config loop_body)
           cf ctx
-    | A.Switch switch -> eval_switch config switch cf ctx
+    | Switch switch -> eval_switch config switch cf ctx
   in
   (* Compose and apply *)
   comp cc cf_eval_st cf ctx
 
-and eval_global (config : C.config) (dest : E.place) (gid : LA.GlobalDeclId.id)
-    : st_cm_fun =
+and eval_global (config : config) (dest : place) (gid : GlobalDeclId.id) :
+    st_cm_fun =
  fun cf ctx ->
-  let global = C.ctx_lookup_global_decl ctx gid in
+  let global = ctx_lookup_global_decl ctx gid in
   match config.mode with
   | ConcreteMode ->
       (* Treat the evaluation of the global as a call to the global body (without arguments) *)
       let func =
         {
-          E.func = FunId (Regular global.body_id);
-          generics = TypesUtils.mk_empty_generic_args;
+          func = FunId (FRegular global.body);
+          generics = TypesUtils.empty_generic_args;
           trait_and_method_generic_args = None;
         }
       in
-      let call = { A.func; args = []; dest } in
-      (eval_transparent_function_call_concrete config global.body_id call)
-        cf ctx
+      let call = { func; args = []; dest } in
+      (eval_transparent_function_call_concrete config global.body call) cf ctx
   | SymbolicMode ->
       (* Generate a fresh symbolic value. In the translation, this fresh symbolic value will be
        * defined as equal to the value of the global (see {!S.synthesize_global_eval}). *)
-      let sval =
-        mk_fresh_symbolic_value V.Global (ety_no_regions_to_rty global.ty)
-      in
+      assert (ty_no_regions global.ty);
+      let sval = mk_fresh_symbolic_value Global global.ty in
       let cc =
         assign_to_place config (mk_typed_value_from_symbolic_value sval) dest
       in
@@ -789,7 +775,7 @@ and eval_global (config : C.config) (dest : E.place) (gid : LA.GlobalDeclId.id)
       S.synthesize_global_eval gid sval e
 
 (** Evaluate a switch *)
-and eval_switch (config : C.config) (switch : A.switch) : st_cm_fun =
+and eval_switch (config : config) (switch : switch) : st_cm_fun =
  fun cf ctx ->
   (* We evaluate the operand in two steps:
    * first we prepare it, then we check if its value is concrete or
@@ -803,14 +789,14 @@ and eval_switch (config : C.config) (switch : A.switch) : st_cm_fun =
   let cf_match : st_cm_fun =
    fun cf ctx ->
     match switch with
-    | A.If (op, st1, st2) ->
+    | If (op, st1, st2) ->
         (* Evaluate the operand *)
         let cf_eval_op = eval_operand config op in
         (* Switch on the value *)
-        let cf_if (cf : st_m_fun) (op_v : V.typed_value) : m_fun =
+        let cf_if (cf : st_m_fun) (op_v : typed_value) : m_fun =
          fun ctx ->
           match op_v.value with
-          | V.Literal (PV.Bool b) ->
+          | VLiteral (VBool b) ->
               (* Evaluate the if and the branch body *)
               let cf_branch cf : m_fun =
                 (* Branch *)
@@ -819,7 +805,7 @@ and eval_switch (config : C.config) (switch : A.switch) : st_cm_fun =
               in
               (* Compose the continuations *)
               cf_branch cf ctx
-          | V.Symbolic sv ->
+          | VSymbolic sv ->
               (* Expand the symbolic boolean, and continue by evaluating
                * the branches *)
               let cf_true : st_cm_fun = eval_statement config st1 in
@@ -831,18 +817,18 @@ and eval_switch (config : C.config) (switch : A.switch) : st_cm_fun =
         in
         (* Compose *)
         comp cf_eval_op cf_if cf ctx
-    | A.SwitchInt (op, int_ty, stgts, otherwise) ->
+    | SwitchInt (op, int_ty, stgts, otherwise) ->
         (* Evaluate the operand *)
         let cf_eval_op = eval_operand config op in
         (* Switch on the value *)
-        let cf_switch (cf : st_m_fun) (op_v : V.typed_value) : m_fun =
+        let cf_switch (cf : st_m_fun) (op_v : typed_value) : m_fun =
          fun ctx ->
           match op_v.value with
-          | V.Literal (PV.Scalar sv) ->
+          | VLiteral (VScalar sv) ->
               (* Evaluate the branch *)
               let cf_eval_branch cf =
                 (* Sanity check *)
-                assert (sv.PV.int_ty = int_ty);
+                assert (sv.int_ty = int_ty);
                 (* Find the branch *)
                 match List.find_opt (fun (svl, _) -> List.mem sv svl) stgts with
                 | None -> eval_statement config otherwise cf
@@ -850,7 +836,7 @@ and eval_switch (config : C.config) (switch : A.switch) : st_cm_fun =
               in
               (* Compose *)
               cf_eval_branch cf ctx
-          | V.Symbolic sv ->
+          | VSymbolic sv ->
               (* Expand the symbolic value and continue by evaluating the
                * proper branches *)
               let stgts =
@@ -878,7 +864,7 @@ and eval_switch (config : C.config) (switch : A.switch) : st_cm_fun =
         in
         (* Compose *)
         comp cf_eval_op cf_switch cf ctx
-    | A.Match (p, stgts, otherwise) ->
+    | Match (p, stgts, otherwise) ->
         (* Access the place *)
         let access = Read in
         let expand_prim_copy = false in
@@ -886,21 +872,21 @@ and eval_switch (config : C.config) (switch : A.switch) : st_cm_fun =
           access_rplace_reorganize_and_read config expand_prim_copy access p cf
         in
         (* Match on the value *)
-        let cf_match (cf : st_m_fun) (p_v : V.typed_value) : m_fun =
+        let cf_match (cf : st_m_fun) (p_v : typed_value) : m_fun =
          fun ctx ->
           (* The value may be shared: we need to ignore the shared loans
              to read the value itself *)
           let p_v = value_strip_shared_loans p_v in
           (* Match *)
           match p_v.value with
-          | V.Adt adt -> (
+          | VAdt adt -> (
               (* Evaluate the discriminant *)
               let dv = Option.get adt.variant_id in
               (* Find the branch, evaluate and continue *)
               match List.find_opt (fun (svl, _) -> List.mem dv svl) stgts with
               | None -> eval_statement config otherwise cf ctx
               | Some (_, tgt) -> eval_statement config tgt cf ctx)
-          | V.Symbolic sv ->
+          | VSymbolic sv ->
               (* Expand the symbolic value - may lead to branching *)
               let cf_expand =
                 expand_symbolic_adt config sv (Some (S.mk_mplace p ctx))
@@ -917,23 +903,22 @@ and eval_switch (config : C.config) (switch : A.switch) : st_cm_fun =
   cf_match cf ctx
 
 (** Evaluate a function call (auxiliary helper for [eval_statement]) *)
-and eval_function_call (config : C.config) (call : A.call) : st_cm_fun =
+and eval_function_call (config : config) (call : call) : st_cm_fun =
   (* There are several cases:
      - this is a local function, in which case we execute its body
      - this is an assumed function, in which case there is a special treatment
      - this is a trait method
   *)
   match config.mode with
-  | C.ConcreteMode -> eval_function_call_concrete config call
-  | C.SymbolicMode -> eval_function_call_symbolic config call
+  | ConcreteMode -> eval_function_call_concrete config call
+  | SymbolicMode -> eval_function_call_symbolic config call
 
-and eval_function_call_concrete (config : C.config) (call : A.call) : st_cm_fun
-    =
+and eval_function_call_concrete (config : config) (call : call) : st_cm_fun =
  fun cf ctx ->
   match call.func.func with
-  | FunId (Regular fid) ->
+  | FunId (FRegular fid) ->
       eval_transparent_function_call_concrete config fid call cf ctx
-  | FunId (Assumed fid) ->
+  | FunId (FAssumed fid) ->
       (* Continue - note that we do as if the function call has been successful,
        * by giving {!Unit} to the continuation, because we place us in the case
        * where we haven't panicked. Of course, the translation needs to take the
@@ -941,25 +926,24 @@ and eval_function_call_concrete (config : C.config) (call : A.call) : st_cm_fun
       eval_assumed_function_call_concrete config fid call (cf Unit) ctx
   | TraitMethod _ -> raise (Failure "Unimplemented")
 
-and eval_function_call_symbolic (config : C.config) (call : A.call) : st_cm_fun
-    =
+and eval_function_call_symbolic (config : config) (call : call) : st_cm_fun =
   match call.func.func with
-  | FunId (Regular _) | TraitMethod _ ->
+  | FunId (FRegular _) | TraitMethod _ ->
       eval_transparent_function_call_symbolic config call
-  | FunId (Assumed fid) -> eval_assumed_function_call_symbolic config fid call
+  | FunId (FAssumed fid) -> eval_assumed_function_call_symbolic config fid call
 
 (** Evaluate a local (i.e., non-assumed) function call in concrete mode *)
-and eval_transparent_function_call_concrete (config : C.config)
-    (fid : A.FunDeclId.id) (call : A.call) : st_cm_fun =
+and eval_transparent_function_call_concrete (config : config)
+    (fid : FunDeclId.id) (call : call) : st_cm_fun =
   let generics = call.func.generics in
-  let args = call.A.args in
-  let dest = call.A.dest in
+  let args = call.args in
+  let dest = call.dest in
   (* Sanity check: we don't fully handle the const generic vars environment
      in concrete mode yet *)
   assert (generics.const_generics = []);
   fun cf ctx ->
     (* Retrieve the (correctly instantiated) body *)
-    let def = C.ctx_lookup_fun_decl ctx fid in
+    let def = ctx_lookup_fun_decl ctx fid in
     (* We can evaluate the function call only if it is not opaque *)
     let body =
       match def.body with
@@ -967,20 +951,20 @@ and eval_transparent_function_call_concrete (config : C.config)
           raise
             (Failure
                ("Can't evaluate a call to an opaque function: "
-               ^ Print.name_to_string def.name))
+               ^ name_to_string ctx def.name))
       | Some body -> body
     in
     (* TODO: we need to normalize the types if we want to correctly support traits *)
     assert (generics.trait_refs = []);
     (* There shouldn't be any reference to Self *)
-    let tr_self = T.UnknownTrait __FUNCTION__ in
+    let tr_self = UnknownTrait __FUNCTION__ in
     let subst =
-      Subst.make_esubst_from_generics def.A.signature.generics generics tr_self
+      Subst.make_subst_from_generics def.signature.generics generics tr_self
     in
     let locals, body_st = Subst.fun_body_substitute_in_body subst body in
 
     (* Evaluate the input operands *)
-    assert (List.length args = body.A.arg_count);
+    assert (List.length args = body.arg_count);
     let cc = eval_operands config args in
 
     (* Push a frame delimiter - we use {!comp_transmit} to transmit the result
@@ -996,7 +980,7 @@ and eval_transparent_function_call_concrete (config : C.config)
       | _ -> raise (Failure "Unreachable")
     in
     let input_locals, locals =
-      Collections.List.split_at locals body.A.arg_count
+      Collections.List.split_at locals body.arg_count
     in
 
     let cc = comp_transmit cc (push_var ret_var (mk_bottom ret_var.var_ty)) in
@@ -1034,8 +1018,8 @@ and eval_transparent_function_call_concrete (config : C.config)
     cc cf ctx
 
 (** Evaluate a local (i.e., non-assumed) function call in symbolic mode *)
-and eval_transparent_function_call_symbolic (config : C.config) (call : A.call)
-    : st_cm_fun =
+and eval_transparent_function_call_symbolic (config : config) (call : call) :
+    st_cm_fun =
  fun cf ctx ->
   (* Instantiate the signature and introduce fresh abstractions and region ids while doing so.
 
@@ -1106,21 +1090,26 @@ and eval_transparent_function_call_symbolic (config : C.config) (call : A.call)
   *)
   let func, generics, def, inst_sg =
     match call.func.func with
-    | FunId (Regular fid) ->
-        let def = C.ctx_lookup_fun_decl ctx fid in
+    | FunId (FRegular fid) ->
+        let def = ctx_lookup_fun_decl ctx fid in
         log#ldebug
           (lazy
             ("fun call:\n- call: " ^ call_to_string ctx call
            ^ "\n- call.generics:\n"
-            ^ egeneric_args_to_string ctx call.func.generics
+            ^ generic_args_to_string ctx call.func.generics
             ^ "\n- def.signature:\n"
-            ^ fun_sig_to_string ctx def.A.signature));
-        let tr_self = T.UnknownTrait __FUNCTION__ in
+            ^ fun_sig_to_string ctx def.signature));
+        let tr_self = UnknownTrait __FUNCTION__ in
+        let regions_hierarchy =
+          LlbcAstUtils.FunIdMap.find (FRegular fid)
+            ctx.fun_context.regions_hierarchies
+        in
         let inst_sg =
-          instantiate_fun_sig ctx call.func.generics tr_self def.A.signature
+          instantiate_fun_sig ctx call.func.generics tr_self def.signature
+            regions_hierarchy
         in
         (call.func.func, call.func.generics, def, inst_sg)
-    | FunId (Assumed _) ->
+    | FunId (FAssumed _) ->
         (* Unreachable: must be a transparent function *)
         raise (Failure "Unreachable")
     | TraitMethod (trait_ref, method_name, _) -> (
@@ -1128,9 +1117,9 @@ and eval_transparent_function_call_symbolic (config : C.config) (call : A.call)
           (lazy
             ("trait method call:\n- call: " ^ call_to_string ctx call
            ^ "\n- method name: " ^ method_name ^ "\n- call.generics:\n"
-            ^ egeneric_args_to_string ctx call.func.generics
+            ^ generic_args_to_string ctx call.func.generics
             ^ "\n- trait and method generics:\n"
-            ^ egeneric_args_to_string ctx
+            ^ generic_args_to_string ctx
                 (Option.get call.func.trait_and_method_generic_args)));
         (* When instantiating, we need to group the generics for the trait ref
            and the method *)
@@ -1141,7 +1130,7 @@ and eval_transparent_function_call_symbolic (config : C.config) (call : A.call)
         match trait_ref.trait_id with
         | TraitImpl impl_id -> (
             (* Lookup the trait impl *)
-            let trait_impl = C.ctx_lookup_trait_impl ctx impl_id in
+            let trait_impl = ctx_lookup_trait_impl ctx impl_id in
             log#ldebug
               (lazy ("trait impl: " ^ trait_impl_to_string ctx trait_impl));
             (* First look in the required methods *)
@@ -1153,14 +1142,17 @@ and eval_transparent_function_call_symbolic (config : C.config) (call : A.call)
             match method_id with
             | Some (_, id) ->
                 (* This is a required method *)
-                let method_def = C.ctx_lookup_fun_decl ctx id in
+                let method_def = ctx_lookup_fun_decl ctx id in
                 (* Instantiate *)
-                let tr_self =
-                  T.TraitRef (etrait_ref_no_regions_to_gr_trait_ref trait_ref)
+                let tr_self = TraitRef trait_ref in
+                let fid : fun_id = FRegular id in
+                let regions_hierarchy =
+                  LlbcAstUtils.FunIdMap.find fid
+                    ctx.fun_context.regions_hierarchies
                 in
                 let inst_sg =
-                  instantiate_fun_sig ctx generics tr_self
-                    method_def.A.signature
+                  instantiate_fun_sig ctx generics tr_self method_def.signature
+                    regions_hierarchy
                 in
                 (* Also update the function identifier: we want to forget
                    the fact that we called a trait method, and treat it as
@@ -1168,14 +1160,14 @@ and eval_transparent_function_call_symbolic (config : C.config) (call : A.call)
                    which implements the method. In order to do this properly,
                    we also need to update the generics.
                 *)
-                let func = E.FunId (Regular id) in
+                let func = FunId fid in
                 (func, generics, method_def, inst_sg)
             | None ->
                 (* If not found, lookup the methods provided by the trait *declaration*
                    (remember: for now, we forbid overriding provided methods) *)
                 assert (trait_impl.provided_methods = []);
                 let trait_decl =
-                  C.ctx_lookup_trait_decl ctx
+                  ctx_lookup_trait_decl ctx
                     trait_ref.trait_decl_ref.trait_decl_id
                 in
                 let _, method_id =
@@ -1184,7 +1176,7 @@ and eval_transparent_function_call_symbolic (config : C.config) (call : A.call)
                     trait_decl.provided_methods
                 in
                 let method_id = Option.get method_id in
-                let method_def = C.ctx_lookup_fun_decl ctx method_id in
+                let method_def = ctx_lookup_fun_decl ctx method_id in
                 (* For the instantiation we have to do something peculiar
                    because the method was defined for the trait declaration.
                    We have to group:
@@ -1210,22 +1202,24 @@ and eval_transparent_function_call_symbolic (config : C.config) (call : A.call)
                   (lazy
                     ("provided method call:" ^ "\n- method name: " ^ method_name
                    ^ "\n- all_generics:\n"
-                    ^ egeneric_args_to_string ctx all_generics
+                    ^ generic_args_to_string ctx all_generics
                     ^ "\n- parent params info: "
-                    ^ Print.option_to_string A.show_params_info
+                    ^ Print.option_to_string show_params_info
                         method_def.signature.parent_params_info));
-                let tr_self =
-                  T.TraitRef (etrait_ref_no_regions_to_gr_trait_ref trait_ref)
+                let regions_hierarchy =
+                  LlbcAstUtils.FunIdMap.find (FRegular method_id)
+                    ctx.fun_context.regions_hierarchies
                 in
+                let tr_self = TraitRef trait_ref in
                 let inst_sg =
                   instantiate_fun_sig ctx all_generics tr_self
-                    method_def.A.signature
+                    method_def.signature regions_hierarchy
                 in
                 (call.func.func, call.func.generics, method_def, inst_sg))
         | _ ->
             (* We are using a local clause - we lookup the trait decl *)
             let trait_decl =
-              C.ctx_lookup_trait_decl ctx trait_ref.trait_decl_ref.trait_decl_id
+              ctx_lookup_trait_decl ctx trait_ref.trait_decl_ref.trait_decl_id
             in
             (* Lookup the method decl in the required *and* the provided methods *)
             let _, method_id =
@@ -1239,21 +1233,22 @@ and eval_transparent_function_call_symbolic (config : C.config) (call : A.call)
                 (fun (s, _) -> s = method_name)
                 (List.append trait_decl.required_methods provided)
             in
-            let method_def = C.ctx_lookup_fun_decl ctx method_id in
+            let method_def = ctx_lookup_fun_decl ctx method_id in
             log#ldebug (lazy ("method:\n" ^ fun_decl_to_string ctx method_def));
             (* Instantiate *)
-            let tr_self = T.TraitRef trait_ref in
-            let tr_self =
-              TypesUtils.etrait_instance_id_no_regions_to_gr_trait_instance_id
-                tr_self
+            let regions_hierarchy =
+              LlbcAstUtils.FunIdMap.find (FRegular method_id)
+                ctx.fun_context.regions_hierarchies
             in
+            let tr_self = TraitRef trait_ref in
             let inst_sg =
-              instantiate_fun_sig ctx generics tr_self method_def.A.signature
+              instantiate_fun_sig ctx generics tr_self method_def.signature
+                regions_hierarchy
             in
             (call.func.func, call.func.generics, method_def, inst_sg))
   in
   (* Sanity check *)
-  assert (List.length call.args = List.length def.A.signature.inputs);
+  assert (List.length call.args = List.length def.signature.inputs);
   (* Evaluate the function call *)
   eval_function_call_symbolic_from_inst_sig config func inst_sg generics
     call.args call.dest cf ctx
@@ -1269,10 +1264,9 @@ and eval_transparent_function_call_symbolic (config : C.config) (call : A.call)
     overriding them. We treat them as regular method, which take an additional
     trait ref as input.
  *)
-and eval_function_call_symbolic_from_inst_sig (config : C.config)
-    (fid : A.fun_id_or_trait_method_ref) (inst_sg : A.inst_fun_sig)
-    (generics : T.egeneric_args) (args : E.operand list) (dest : E.place) :
-    st_cm_fun =
+and eval_function_call_symbolic_from_inst_sig (config : config)
+    (fid : fun_id_or_trait_method_ref) (inst_sg : inst_fun_sig)
+    (generics : generic_args) (args : operand list) (dest : place) : st_cm_fun =
  fun cf ctx ->
   log#ldebug
     (lazy
@@ -1281,14 +1275,14 @@ and eval_function_call_symbolic_from_inst_sig (config : C.config)
       ^ "\n- inst_sg:\n"
       ^ inst_fun_sig_to_string ctx inst_sg
       ^ "\n- call.generics:\n"
-      ^ egeneric_args_to_string ctx generics
+      ^ generic_args_to_string ctx generics
       ^ "\n- args:\n"
       ^ String.concat ", " (List.map (operand_to_string ctx) args)
       ^ "\n- dest:\n" ^ place_to_string ctx dest));
 
   (* Generate a fresh symbolic value for the return value *)
-  let ret_sv_ty = inst_sg.A.output in
-  let ret_spc = mk_fresh_symbolic_value V.FunCallRet ret_sv_ty in
+  let ret_sv_ty = inst_sg.output in
+  let ret_spc = mk_fresh_symbolic_value FunCallRet ret_sv_ty in
   let ret_value = mk_typed_value_from_symbolic_value ret_spc in
   let ret_av regions =
     mk_aproj_loans_value_from_symbolic_value regions ret_spc
@@ -1300,16 +1294,16 @@ and eval_function_call_symbolic_from_inst_sig (config : C.config)
   let cc = eval_operands config args in
 
   (* Generate the abstractions and insert them in the context *)
-  let abs_ids = List.map (fun rg -> rg.T.id) inst_sg.regions_hierarchy in
-  let cf_call cf (args : V.typed_value list) : m_fun =
+  let abs_ids = List.map (fun rg -> rg.id) inst_sg.regions_hierarchy in
+  let cf_call cf (args : typed_value list) : m_fun =
    fun ctx ->
-    let args_with_rtypes = List.combine args inst_sg.A.inputs in
+    let args_with_rtypes = List.combine args inst_sg.inputs in
 
     (* Check the type of the input arguments *)
     assert (
       List.for_all
-        (fun ((arg, rty) : V.typed_value * T.rty) ->
-          arg.V.ty = Subst.erase_regions rty)
+        (fun ((arg, rty) : typed_value * rty) ->
+          arg.ty = Subst.erase_regions rty)
         args_with_rtypes);
     (* Check that the input arguments don't contain symbolic values that can't 
      * be fed to functions (i.e., symbolic values output from function return
@@ -1325,8 +1319,8 @@ and eval_function_call_symbolic_from_inst_sig (config : C.config)
      * First, we define the function which, given an initialized, empty
      * abstraction, computes the avalues which should be inserted inside.
      *)
-    let compute_abs_avalues (abs : V.abs) (ctx : C.eval_ctx) :
-        C.eval_ctx * V.typed_avalue list =
+    let compute_abs_avalues (abs : abs) (ctx : eval_ctx) :
+        eval_ctx * typed_avalue list =
       (* Project over the input values *)
       let ctx, args_projs =
         List.fold_left_map
@@ -1339,12 +1333,12 @@ and eval_function_call_symbolic_from_inst_sig (config : C.config)
       (ctx, List.append args_projs [ ret_av abs.regions ])
     in
     (* Actually initialize and insert the abstractions *)
-    let call_id = C.fresh_fun_call_id () in
+    let call_id = fresh_fun_call_id () in
     let region_can_end _ = true in
     let ctx =
       create_push_abstractions_from_abs_region_groups
-        (fun rg_id -> V.FunCall (call_id, rg_id))
-        inst_sg.A.regions_hierarchy region_can_end compute_abs_avalues ctx
+        (fun rg_id -> FunCall (call_id, rg_id))
+        inst_sg.regions_hierarchy region_can_end compute_abs_avalues ctx
     in
 
     (* Apply the continuation *)
@@ -1372,9 +1366,9 @@ and eval_function_call_symbolic_from_inst_sig (config : C.config)
       List.partition
         (fun abs_id ->
           (* Lookup the abstraction *)
-          let abs = C.ctx_lookup_abs ctx abs_id in
+          let abs = ctx_lookup_abs ctx abs_id in
           (* Check if it has parents *)
-          V.AbstractionId.Set.is_empty abs.parents
+          AbstractionId.Set.is_empty abs.parents
           (* Check if it contains non-ignored loans *)
           && Option.is_none
                (InterpreterBorrowsCore
@@ -1386,7 +1380,7 @@ and eval_function_call_symbolic_from_inst_sig (config : C.config)
       (* Update the reference to the list of asbtraction ids, for the recursive calls *)
       abs_ids := with_loans_abs;
       (* End the abstractions which can be ended *)
-      let no_loans_abs = V.AbstractionId.Set.of_list no_loans_abs in
+      let no_loans_abs = AbstractionId.Set.of_list no_loans_abs in
       let cc = InterpreterBorrows.end_abstractions config no_loans_abs in
       (* Recursive call *)
       let cc = comp cc end_abs_with_no_loans in
@@ -1413,8 +1407,8 @@ and eval_function_call_symbolic_from_inst_sig (config : C.config)
   cc (cf Unit) ctx
 
 (** Evaluate a non-local function call in symbolic mode *)
-and eval_assumed_function_call_symbolic (config : C.config)
-    (fid : A.assumed_fun_id) (call : A.call) : st_cm_fun =
+and eval_assumed_function_call_symbolic (config : config) (fid : assumed_fun_id)
+    (call : call) : st_cm_fun =
  fun cf ctx ->
   let generics = call.func.generics in
   let args = call.args in
@@ -1444,21 +1438,26 @@ and eval_assumed_function_call_symbolic (config : C.config)
       let inst_sig =
         match fid with
         | BoxFree ->
-            (* should have been treated above *)
+            (* Should have been treated above *)
             raise (Failure "Unreachable")
         | _ ->
+            let regions_hierarchy =
+              LlbcAstUtils.FunIdMap.find (FAssumed fid)
+                ctx.fun_context.regions_hierarchies
+            in
             (* There shouldn't be any reference to Self *)
-            let tr_self = T.UnknownTrait __FUNCTION__ in
+            let tr_self = UnknownTrait __FUNCTION__ in
             instantiate_fun_sig ctx generics tr_self
               (Assumed.get_assumed_fun_sig fid)
+              regions_hierarchy
       in
 
       (* Evaluate the function call *)
-      eval_function_call_symbolic_from_inst_sig config (FunId (Assumed fid))
+      eval_function_call_symbolic_from_inst_sig config (FunId (FAssumed fid))
         inst_sig generics args dest cf ctx
 
 (** Evaluate a statement seen as a function body *)
-and eval_function_body (config : C.config) (body : A.statement) : st_cm_fun =
+and eval_function_body (config : config) (body : statement) : st_cm_fun =
  fun cf ctx ->
   let cc = eval_statement config body in
   let cf_finish cf res =
@@ -1468,7 +1467,7 @@ and eval_function_body (config : C.config) (body : A.statement) : st_cm_fun =
      * checking the invariants *)
     let cc = greedy_expand_symbolic_values config in
     (* Sanity check *)
-    let cc = comp_check_ctx cc Inv.check_invariants in
+    let cc = comp_check_ctx cc Invariants.check_invariants in
     (* Continue *)
     cc (cf res)
   in
diff --git a/compiler/InterpreterStatements.mli b/compiler/InterpreterStatements.mli
index e65758ae..d84e8be6 100644
--- a/compiler/InterpreterStatements.mli
+++ b/compiler/InterpreterStatements.mli
@@ -1,15 +1,8 @@
-module T = Types
-module PV = PrimitiveValues
-module V = Values
-module E = Expressions
-module C = Contexts
-module Subst = Substitute
-module A = LlbcAst
-module L = Logging
-module Inv = Invariants
-module S = SynthesizeSymbolic
+open Types
+open Values
+open Contexts
+open LlbcAst
 open Cps
-open InterpreterExpressions
 
 (** Pop the current frame.
 
@@ -17,13 +10,13 @@ open InterpreterExpressions
     dummy variables, after ending the proper borrows of course) but the return
     variable, move the return value out of the return variable, remove all the
     local variables (but preserve the abstractions!), remove the
-    {!constructor:C.env_elem.Frame} indicator delimiting the current frame and
+    {!constructor:env_elem.Frame} indicator delimiting the current frame and
     handle the return value to the continuation.
 
     If the boolean is false, we don't move the return value, and call the
     continuation with [None].
  *)
-val pop_frame : C.config -> bool -> (V.typed_value option -> m_fun) -> m_fun
+val pop_frame : config -> bool -> (typed_value option -> m_fun) -> m_fun
 
 (** Helper.
 
@@ -44,15 +37,15 @@ val pop_frame : C.config -> bool -> (V.typed_value option -> m_fun) -> m_fun
     - [ctx]
 *)
 val create_push_abstractions_from_abs_region_groups :
-  (T.RegionGroupId.id -> V.abs_kind) ->
-  LA.abs_region_group list ->
-  (T.RegionGroupId.id -> bool) ->
-  (V.abs -> C.eval_ctx -> C.eval_ctx * V.typed_avalue list) ->
-  C.eval_ctx ->
-  C.eval_ctx
+  (RegionGroupId.id -> abs_kind) ->
+  abs_region_group list ->
+  (RegionGroupId.id -> bool) ->
+  (abs -> eval_ctx -> eval_ctx * typed_avalue list) ->
+  eval_ctx ->
+  eval_ctx
 
 (** Evaluate a statement *)
-val eval_statement : C.config -> LA.statement -> st_cm_fun
+val eval_statement : config -> statement -> st_cm_fun
 
 (** Evaluate a statement seen as a function body *)
-val eval_function_body : C.config -> LA.statement -> st_cm_fun
+val eval_function_body : config -> statement -> st_cm_fun
diff --git a/compiler/InterpreterUtils.ml b/compiler/InterpreterUtils.ml
index 6e08e553..ecd8f53f 100644
--- a/compiler/InterpreterUtils.ml
+++ b/compiler/InterpreterUtils.ml
@@ -1,25 +1,22 @@
-module T = Types
-module V = Values
-module E = Expressions
-module C = Contexts
-module Subst = Substitute
-module A = LlbcAst
-module L = Logging
+open Types
+open Values
+open Expressions
+open Contexts
+open LlbcAst
 open Utils
 open TypesUtils
-module PA = Print.EvalCtxLlbcAst
 open Cps
 
 (* TODO: we should probably rename the file to ContextsUtils *)
 
 (** The local logger *)
-let log = L.interpreter_log
+let log = Logging.interpreter_log
 
 (** Some utilities *)
 
 (** Auxiliary function - call a function which requires a continuation,
     and return the let context given to the continuation *)
-let get_cf_ctx_no_synth (f : cm_fun) (ctx : C.eval_ctx) : C.eval_ctx =
+let get_cf_ctx_no_synth (f : cm_fun) (ctx : eval_ctx) : eval_ctx =
   let nctx = ref None in
   let cf ctx =
     assert (!nctx = None);
@@ -31,117 +28,120 @@ let get_cf_ctx_no_synth (f : cm_fun) (ctx : C.eval_ctx) : C.eval_ctx =
 
 let eval_ctx_to_string_no_filter = Print.Contexts.eval_ctx_to_string_no_filter
 let eval_ctx_to_string = Print.Contexts.eval_ctx_to_string
-let ety_to_string = PA.ety_to_string
-let rty_to_string = PA.rty_to_string
-let symbolic_value_to_string = PA.symbolic_value_to_string
-let borrow_content_to_string = PA.borrow_content_to_string
-let loan_content_to_string = PA.loan_content_to_string
-let aborrow_content_to_string = PA.aborrow_content_to_string
-let aloan_content_to_string = PA.aloan_content_to_string
-let aproj_to_string = PA.aproj_to_string
-let typed_value_to_string = PA.typed_value_to_string
-let typed_avalue_to_string = PA.typed_avalue_to_string
-let place_to_string = PA.place_to_string
-let operand_to_string = PA.operand_to_string
-let egeneric_args_to_string = PA.egeneric_args_to_string
-let rtrait_instance_id_to_string = PA.rtrait_instance_id_to_string
-let fun_sig_to_string = PA.fun_sig_to_string
-let inst_fun_sig_to_string = PA.inst_fun_sig_to_string
+let name_to_string = Print.EvalCtx.name_to_string
+let symbolic_value_to_string = Print.EvalCtx.symbolic_value_to_string
+let borrow_content_to_string = Print.EvalCtx.borrow_content_to_string
+let loan_content_to_string = Print.EvalCtx.loan_content_to_string
+let aborrow_content_to_string = Print.EvalCtx.aborrow_content_to_string
+let aloan_content_to_string = Print.EvalCtx.aloan_content_to_string
+let aproj_to_string = Print.EvalCtx.aproj_to_string
+let typed_value_to_string = Print.EvalCtx.typed_value_to_string
+let typed_avalue_to_string = Print.EvalCtx.typed_avalue_to_string
+let place_to_string = Print.EvalCtx.place_to_string
+let operand_to_string = Print.EvalCtx.operand_to_string
+let fun_sig_to_string = Print.EvalCtx.fun_sig_to_string
+let inst_fun_sig_to_string = Print.EvalCtx.inst_fun_sig_to_string
+let ty_to_string = Print.EvalCtx.ty_to_string
+let generic_args_to_string = Print.EvalCtx.generic_args_to_string
 
 let fun_id_or_trait_method_ref_to_string =
-  PA.fun_id_or_trait_method_ref_to_string
+  Print.EvalCtx.fun_id_or_trait_method_ref_to_string
 
-let fun_decl_to_string = PA.fun_decl_to_string
-let call_to_string = PA.call_to_string
+let fun_decl_to_string = Print.EvalCtx.fun_decl_to_string
+let call_to_string = Print.EvalCtx.call_to_string
 
 let trait_impl_to_string ctx =
-  PA.trait_impl_to_string { ctx with type_vars = []; const_generic_vars = [] }
+  Print.EvalCtx.trait_impl_to_string
+    { ctx with type_vars = []; const_generic_vars = [] }
 
-let statement_to_string ctx = PA.statement_to_string ctx "" "  "
-let statement_to_string_with_tab ctx = PA.statement_to_string ctx "  " "  "
-let env_elem_to_string ctx = PA.env_elem_to_string ctx "" "  "
+let statement_to_string ctx = Print.EvalCtx.statement_to_string ctx "" "  "
+
+let statement_to_string_with_tab ctx =
+  Print.EvalCtx.statement_to_string ctx "  " "  "
+
+let env_elem_to_string ctx = Print.EvalCtx.env_elem_to_string ctx "" "  "
 let env_to_string ctx env = eval_ctx_to_string { ctx with env }
-let abs_to_string ctx = PA.abs_to_string ctx "" "  "
+let abs_to_string ctx = Print.EvalCtx.abs_to_string ctx "" "  "
 
-let same_symbolic_id (sv0 : V.symbolic_value) (sv1 : V.symbolic_value) : bool =
-  sv0.V.sv_id = sv1.V.sv_id
+let same_symbolic_id (sv0 : symbolic_value) (sv1 : symbolic_value) : bool =
+  sv0.sv_id = sv1.sv_id
 
-let mk_var (index : E.VarId.id) (name : string option) (var_ty : T.ety) : A.var
-    =
-  { A.index; name; var_ty }
+let mk_var (index : VarId.id) (name : string option) (var_ty : ty) : var =
+  { index; name; var_ty }
 
 (** Small helper - TODO: move *)
-let mk_place_from_var_id (var_id : E.VarId.id) : E.place =
+let mk_place_from_var_id (var_id : VarId.id) : place =
   { var_id; projection = [] }
 
 (** Create a fresh symbolic value *)
-let mk_fresh_symbolic_value (sv_kind : V.sv_kind) (ty : T.rty) :
-    V.symbolic_value =
-  let sv_id = C.fresh_symbolic_value_id () in
-  let svalue = { V.sv_kind; V.sv_id; V.sv_ty = ty } in
+let mk_fresh_symbolic_value (sv_kind : sv_kind) (ty : ty) : symbolic_value =
+  (* Sanity check *)
+  assert (ty_is_rty ty);
+  let sv_id = fresh_symbolic_value_id () in
+  let svalue = { sv_kind; sv_id; sv_ty = ty } in
   svalue
 
+let mk_fresh_symbolic_value_from_no_regions_ty (sv_kind : sv_kind) (ty : ty) :
+    symbolic_value =
+  assert (ty_no_regions ty);
+  mk_fresh_symbolic_value sv_kind ty
+
 (** Create a fresh symbolic value *)
-let mk_fresh_symbolic_typed_value (sv_kind : V.sv_kind) (rty : T.rty) :
-    V.typed_value =
-  let ty = Subst.erase_regions rty in
+let mk_fresh_symbolic_typed_value (sv_kind : sv_kind) (rty : ty) : typed_value =
+  assert (ty_is_rty rty);
+  let ty = Substitute.erase_regions rty in
   (* Generate the fresh a symbolic value *)
   let value = mk_fresh_symbolic_value sv_kind rty in
-  let value = V.Symbolic value in
-  { V.value; V.ty }
+  let value = VSymbolic value in
+  { value; ty }
 
-(** Create a fresh symbolic value *)
-let mk_fresh_symbolic_typed_value_from_ety (sv_kind : V.sv_kind) (ety : T.ety) :
-    V.typed_value =
-  let ty = TypesUtils.ety_no_regions_to_rty ety in
+let mk_fresh_symbolic_typed_value_from_no_regions_ty (sv_kind : sv_kind)
+    (ty : ty) : typed_value =
+  assert (ty_no_regions ty);
   mk_fresh_symbolic_typed_value sv_kind ty
 
 (** Create a typed value from a symbolic value. *)
-let mk_typed_value_from_symbolic_value (svalue : V.symbolic_value) :
-    V.typed_value =
-  let av = V.Symbolic svalue in
-  let av : V.typed_value =
-    { V.value = av; V.ty = Subst.erase_regions svalue.V.sv_ty }
+let mk_typed_value_from_symbolic_value (svalue : symbolic_value) : typed_value =
+  let av = VSymbolic svalue in
+  let av : typed_value =
+    { value = av; ty = Substitute.erase_regions svalue.sv_ty }
   in
   av
 
 (** Create a loans projector value from a symbolic value.
     
     Checks if the projector will actually project some regions. If not,
-    returns {!V.AIgnored} ([_]).
+    returns {!AIgnored} ([_]).
     
     TODO: update to handle 'static
  *)
-let mk_aproj_loans_value_from_symbolic_value (regions : T.RegionId.Set.t)
-    (svalue : V.symbolic_value) : V.typed_avalue =
+let mk_aproj_loans_value_from_symbolic_value (regions : RegionId.Set.t)
+    (svalue : symbolic_value) : typed_avalue =
   if ty_has_regions_in_set regions svalue.sv_ty then
-    let av = V.ASymbolic (V.AProjLoans (svalue, [])) in
-    let av : V.typed_avalue = { V.value = av; V.ty = svalue.V.sv_ty } in
+    let av = ASymbolic (AProjLoans (svalue, [])) in
+    let av : typed_avalue = { value = av; ty = svalue.sv_ty } in
     av
-  else { V.value = V.AIgnored; ty = svalue.V.sv_ty }
+  else { value = AIgnored; ty = svalue.sv_ty }
 
 (** Create a borrows projector from a symbolic value *)
-let mk_aproj_borrows_from_symbolic_value (proj_regions : T.RegionId.Set.t)
-    (svalue : V.symbolic_value) (proj_ty : T.rty) : V.aproj =
+let mk_aproj_borrows_from_symbolic_value (proj_regions : RegionId.Set.t)
+    (svalue : symbolic_value) (proj_ty : ty) : aproj =
+  assert (ty_is_rty proj_ty);
   if ty_has_regions_in_set proj_regions proj_ty then
-    V.AProjBorrows (svalue, proj_ty)
-  else V.AIgnoredProjBorrows
+    AProjBorrows (svalue, proj_ty)
+  else AIgnoredProjBorrows
 
 (** TODO: move *)
-let borrow_is_asb (bid : V.BorrowId.id) (asb : V.abstract_shared_borrow) : bool
-    =
-  match asb with
-  | V.AsbBorrow bid' -> bid' = bid
-  | V.AsbProjReborrows _ -> false
+let borrow_is_asb (bid : BorrowId.id) (asb : abstract_shared_borrow) : bool =
+  match asb with AsbBorrow bid' -> bid' = bid | AsbProjReborrows _ -> false
 
 (** TODO: move *)
-let borrow_in_asb (bid : V.BorrowId.id) (asb : V.abstract_shared_borrows) : bool
-    =
+let borrow_in_asb (bid : BorrowId.id) (asb : abstract_shared_borrows) : bool =
   List.exists (borrow_is_asb bid) asb
 
 (** TODO: move *)
-let remove_borrow_from_asb (bid : V.BorrowId.id)
-    (asb : V.abstract_shared_borrows) : V.abstract_shared_borrows =
+let remove_borrow_from_asb (bid : BorrowId.id) (asb : abstract_shared_borrows) :
+    abstract_shared_borrows =
   let removed = ref 0 in
   let asb =
     List.filter
@@ -165,26 +165,26 @@ type ('a, 'b) concrete_or_abs = Concrete of 'a | Abstract of 'b
 [@@deriving show]
 
 (** Generic loan content: concrete or abstract *)
-type g_loan_content = (V.loan_content, V.aloan_content) concrete_or_abs
+type g_loan_content = (loan_content, aloan_content) concrete_or_abs
 [@@deriving show]
 
 (** Generic borrow content: concrete or abstract *)
-type g_borrow_content = (V.borrow_content, V.aborrow_content) concrete_or_abs
+type g_borrow_content = (borrow_content, aborrow_content) concrete_or_abs
 [@@deriving show]
 
 type abs_or_var_id =
-  | AbsId of V.AbstractionId.id
-  | VarId of E.VarId.id
-  | DummyVarId of C.DummyVarId.id
+  | AbsId of AbstractionId.id
+  | VarId of VarId.id
+  | DummyVarId of DummyVarId.id
 
 (** Utility exception *)
-exception FoundBorrowContent of V.borrow_content
+exception FoundBorrowContent of borrow_content
 
 (** Utility exception *)
-exception FoundLoanContent of V.loan_content
+exception FoundLoanContent of loan_content
 
 (** Utility exception *)
-exception FoundABorrowContent of V.aborrow_content
+exception FoundABorrowContent of aborrow_content
 
 (** Utility exception *)
 exception FoundGBorrowContent of g_borrow_content
@@ -193,30 +193,30 @@ exception FoundGBorrowContent of g_borrow_content
 exception FoundGLoanContent of g_loan_content
 
 (** Utility exception *)
-exception FoundAProjBorrows of V.symbolic_value * T.rty
+exception FoundAProjBorrows of symbolic_value * ty
 
-let symbolic_value_id_in_ctx (sv_id : V.SymbolicValueId.id) (ctx : C.eval_ctx) :
+let symbolic_value_id_in_ctx (sv_id : SymbolicValueId.id) (ctx : eval_ctx) :
     bool =
   let obj =
     object
-      inherit [_] C.iter_eval_ctx as super
+      inherit [_] iter_eval_ctx as super
 
-      method! visit_Symbolic _ sv =
-        if sv.V.sv_id = sv_id then raise Found else ()
+      method! visit_VSymbolic _ sv =
+        if sv.sv_id = sv_id then raise Found else ()
 
       method! visit_aproj env aproj =
         (match aproj with
         | AProjLoans (sv, _) | AProjBorrows (sv, _) ->
-            if sv.V.sv_id = sv_id then raise Found else ()
+            if sv.sv_id = sv_id then raise Found else ()
         | AEndedProjLoans _ | AEndedProjBorrows _ | AIgnoredProjBorrows -> ());
         super#visit_aproj env aproj
 
       method! visit_abstract_shared_borrows _ asb =
-        let visit (asb : V.abstract_shared_borrow) : unit =
+        let visit (asb : abstract_shared_borrow) : unit =
           match asb with
-          | V.AsbBorrow _ -> ()
-          | V.AsbProjReborrows (sv, _) ->
-              if sv.V.sv_id = sv_id then raise Found else ()
+          | AsbBorrow _ -> ()
+          | AsbProjReborrows (sv, _) ->
+              if sv.sv_id = sv_id then raise Found else ()
         in
         List.iter visit asb
     end
@@ -233,22 +233,21 @@ let symbolic_value_id_in_ctx (sv_id : V.SymbolicValueId.id) (ctx : C.eval_ctx) :
     check that the set of ended regions doesn't intersect the set of
     regions used in the type (this is more general).
 *)
-let symbolic_value_has_ended_regions (ended_regions : T.RegionId.Set.t)
-    (s : V.symbolic_value) : bool =
-  let regions = rty_regions s.V.sv_ty in
-  not (T.RegionId.Set.disjoint regions ended_regions)
+let symbolic_value_has_ended_regions (ended_regions : RegionId.Set.t)
+    (s : symbolic_value) : bool =
+  let regions = ty_regions s.sv_ty in
+  not (RegionId.Set.disjoint regions ended_regions)
 
-(** Check if a {!type:V.value} contains [⊥].
+(** Check if a {!type:value} contains [⊥].
 
     Note that this function is very general: it also checks wether
     symbolic values contain already ended regions.
  *)
-let bottom_in_value (ended_regions : T.RegionId.Set.t) (v : V.typed_value) :
-    bool =
+let bottom_in_value (ended_regions : RegionId.Set.t) (v : typed_value) : bool =
   let obj =
     object
-      inherit [_] V.iter_typed_value
-      method! visit_Bottom _ = raise Found
+      inherit [_] iter_typed_value
+      method! visit_VBottom _ = raise Found
 
       method! visit_symbolic_value _ s =
         if symbolic_value_has_ended_regions ended_regions s then raise Found
@@ -261,21 +260,21 @@ let bottom_in_value (ended_regions : T.RegionId.Set.t) (v : V.typed_value) :
     false
   with Found -> true
 
-let value_has_ret_symbolic_value_with_borrow_under_mut (ctx : C.eval_ctx)
-    (v : V.typed_value) : bool =
+let value_has_ret_symbolic_value_with_borrow_under_mut (ctx : eval_ctx)
+    (v : typed_value) : bool =
   let obj =
     object
-      inherit [_] V.iter_typed_value
+      inherit [_] iter_typed_value
 
       method! visit_symbolic_value _ s =
         match s.sv_kind with
-        | V.FunCallRet | V.LoopOutput | V.LoopJoin ->
+        | FunCallRet | LoopOutput | LoopJoin ->
             if ty_has_borrow_under_mut ctx.type_context.type_infos s.sv_ty then
               raise Found
             else ()
-        | V.SynthInput | V.SynthInputGivenBack | V.FunCallGivenBack
-        | V.SynthRetGivenBack | V.Global | V.LoopGivenBack | V.Aggregate
-        | V.ConstGeneric | V.TraitConst ->
+        | SynthInput | SynthInputGivenBack | FunCallGivenBack
+        | SynthRetGivenBack | Global | LoopGivenBack | Aggregate | ConstGeneric
+        | TraitConst ->
             ()
     end
   in
@@ -288,7 +287,7 @@ let value_has_ret_symbolic_value_with_borrow_under_mut (ctx : C.eval_ctx)
 (** Return the place used in an rvalue, if that makes sense.
     This is used to compute meta-data, to find pretty names.
  *)
-let rvalue_get_place (rv : E.rvalue) : E.place option =
+let rvalue_get_place (rv : rvalue) : place option =
   match rv with
   | Use (Copy p | Move p) -> Some p
   | Use (Constant _) -> None
@@ -296,30 +295,29 @@ let rvalue_get_place (rv : E.rvalue) : E.place option =
   | UnaryOp _ | BinaryOp _ | Global _ | Discriminant _ | Aggregate _ -> None
 
 (** See {!ValuesUtils.symbolic_value_has_borrows} *)
-let symbolic_value_has_borrows (ctx : C.eval_ctx) (sv : V.symbolic_value) : bool
-    =
+let symbolic_value_has_borrows (ctx : eval_ctx) (sv : symbolic_value) : bool =
   ValuesUtils.symbolic_value_has_borrows ctx.type_context.type_infos sv
 
 (** See {!ValuesUtils.value_has_borrows}. *)
-let value_has_borrows (ctx : C.eval_ctx) (v : V.value) : bool =
+let value_has_borrows (ctx : eval_ctx) (v : value) : bool =
   ValuesUtils.value_has_borrows ctx.type_context.type_infos v
 
 (** See {!ValuesUtils.value_has_loans_or_borrows}. *)
-let value_has_loans_or_borrows (ctx : C.eval_ctx) (v : V.value) : bool =
+let value_has_loans_or_borrows (ctx : eval_ctx) (v : value) : bool =
   ValuesUtils.value_has_loans_or_borrows ctx.type_context.type_infos v
 
 (** See {!ValuesUtils.value_has_loans}. *)
-let value_has_loans (v : V.value) : bool = ValuesUtils.value_has_loans v
+let value_has_loans (v : value) : bool = ValuesUtils.value_has_loans v
 
 (** See {!compute_typed_value_ids}, {!compute_context_ids}, etc. *)
 type ids_sets = {
-  aids : V.AbstractionId.Set.t;
-  blids : V.BorrowId.Set.t;  (** All the borrow/loan ids *)
-  borrow_ids : V.BorrowId.Set.t;  (** Only the borrow ids *)
-  loan_ids : V.BorrowId.Set.t;  (** Only the loan ids *)
-  dids : C.DummyVarId.Set.t;
-  rids : T.RegionId.Set.t;
-  sids : V.SymbolicValueId.Set.t;
+  aids : AbstractionId.Set.t;
+  blids : BorrowId.Set.t;  (** All the borrow/loan ids *)
+  borrow_ids : BorrowId.Set.t;  (** Only the borrow ids *)
+  loan_ids : BorrowId.Set.t;  (** Only the loan ids *)
+  dids : DummyVarId.Set.t;
+  rids : RegionId.Set.t;
+  sids : SymbolicValueId.Set.t;
 }
 [@@deriving show]
 
@@ -327,19 +325,17 @@ type ids_sets = {
 
     TODO: there misses information.
  *)
-type ids_to_values = {
-  sids_to_values : V.symbolic_value V.SymbolicValueId.Map.t;
-}
+type ids_to_values = { sids_to_values : symbolic_value SymbolicValueId.Map.t }
 
 let compute_ids () =
-  let blids = ref V.BorrowId.Set.empty in
-  let borrow_ids = ref V.BorrowId.Set.empty in
-  let loan_ids = ref V.BorrowId.Set.empty in
-  let aids = ref V.AbstractionId.Set.empty in
-  let dids = ref C.DummyVarId.Set.empty in
-  let rids = ref T.RegionId.Set.empty in
-  let sids = ref V.SymbolicValueId.Set.empty in
-  let sids_to_values = ref V.SymbolicValueId.Map.empty in
+  let blids = ref BorrowId.Set.empty in
+  let borrow_ids = ref BorrowId.Set.empty in
+  let loan_ids = ref BorrowId.Set.empty in
+  let aids = ref AbstractionId.Set.empty in
+  let dids = ref DummyVarId.Set.empty in
+  let rids = ref RegionId.Set.empty in
+  let sids = ref SymbolicValueId.Set.empty in
+  let sids_to_values = ref SymbolicValueId.Map.empty in
 
   let get_ids () =
     {
@@ -355,171 +351,160 @@ let compute_ids () =
   let get_ids_to_values () = { sids_to_values = !sids_to_values } in
   let obj =
     object
-      inherit [_] C.iter_eval_ctx as super
-      method! visit_dummy_var_id _ did = dids := C.DummyVarId.Set.add did !dids
+      inherit [_] iter_eval_ctx as super
+      method! visit_dummy_var_id _ did = dids := DummyVarId.Set.add did !dids
 
       method! visit_borrow_id _ id =
-        blids := V.BorrowId.Set.add id !blids;
-        borrow_ids := V.BorrowId.Set.add id !borrow_ids
+        blids := BorrowId.Set.add id !blids;
+        borrow_ids := BorrowId.Set.add id !borrow_ids
 
       method! visit_loan_id _ id =
-        blids := V.BorrowId.Set.add id !blids;
-        loan_ids := V.BorrowId.Set.add id !loan_ids
-
-      method! visit_abstraction_id _ id =
-        aids := V.AbstractionId.Set.add id !aids
+        blids := BorrowId.Set.add id !blids;
+        loan_ids := BorrowId.Set.add id !loan_ids
 
-      method! visit_region_id _ id = rids := T.RegionId.Set.add id !rids
+      method! visit_abstraction_id _ id = aids := AbstractionId.Set.add id !aids
+      method! visit_region_id _ id = rids := RegionId.Set.add id !rids
 
       method! visit_symbolic_value env sv =
-        sids := V.SymbolicValueId.Set.add sv.sv_id !sids;
-        sids_to_values := V.SymbolicValueId.Map.add sv.sv_id sv !sids_to_values;
+        sids := SymbolicValueId.Set.add sv.sv_id !sids;
+        sids_to_values := SymbolicValueId.Map.add sv.sv_id sv !sids_to_values;
         super#visit_symbolic_value env sv
 
       method! visit_symbolic_value_id _ id =
         (* TODO: can we get there without going through [visit_symbolic_value] first? *)
-        sids := V.SymbolicValueId.Set.add id !sids
+        sids := SymbolicValueId.Set.add id !sids
     end
   in
   (obj, get_ids, get_ids_to_values)
 
 (** Compute the sets of ids found in a list of typed values. *)
-let compute_typed_values_ids (xl : V.typed_value list) :
-    ids_sets * ids_to_values =
+let compute_typed_values_ids (xl : typed_value list) : ids_sets * ids_to_values
+    =
   let compute, get_ids, get_ids_to_values = compute_ids () in
   List.iter (compute#visit_typed_value ()) xl;
   (get_ids (), get_ids_to_values ())
 
 (** Compute the sets of ids found in a typed value. *)
-let compute_typed_value_ids (x : V.typed_value) : ids_sets * ids_to_values =
+let compute_typed_value_ids (x : typed_value) : ids_sets * ids_to_values =
   compute_typed_values_ids [ x ]
 
 (** Compute the sets of ids found in a list of abstractions. *)
-let compute_absl_ids (xl : V.abs list) : ids_sets * ids_to_values =
+let compute_absl_ids (xl : abs list) : ids_sets * ids_to_values =
   let compute, get_ids, get_ids_to_values = compute_ids () in
   List.iter (compute#visit_abs ()) xl;
   (get_ids (), get_ids_to_values ())
 
 (** Compute the sets of ids found in an abstraction. *)
-let compute_abs_ids (x : V.abs) : ids_sets * ids_to_values =
+let compute_abs_ids (x : abs) : ids_sets * ids_to_values =
   compute_absl_ids [ x ]
 
 (** Compute the sets of ids found in an environment. *)
-let compute_env_ids (x : C.env) : ids_sets * ids_to_values =
+let compute_env_ids (x : env) : ids_sets * ids_to_values =
   let compute, get_ids, get_ids_to_values = compute_ids () in
   compute#visit_env () x;
   (get_ids (), get_ids_to_values ())
 
 (** Compute the sets of ids found in an environment element. *)
-let compute_env_elem_ids (x : C.env_elem) : ids_sets * ids_to_values =
+let compute_env_elem_ids (x : env_elem) : ids_sets * ids_to_values =
   compute_env_ids [ x ]
 
 (** Compute the sets of ids found in a list of contexts. *)
-let compute_contexts_ids (ctxl : C.eval_ctx list) : ids_sets * ids_to_values =
+let compute_contexts_ids (ctxl : eval_ctx list) : ids_sets * ids_to_values =
   let compute, get_ids, get_ids_to_values = compute_ids () in
   List.iter (compute#visit_eval_ctx ()) ctxl;
   (get_ids (), get_ids_to_values ())
 
 (** Compute the sets of ids found in a context. *)
-let compute_context_ids (ctx : C.eval_ctx) : ids_sets * ids_to_values =
+let compute_context_ids (ctx : eval_ctx) : ids_sets * ids_to_values =
   compute_contexts_ids [ ctx ]
 
 (** **WARNING**: this function doesn't compute the normalized types
     (for the trait type aliases). This should be computed afterwards.
  *)
-let initialize_eval_context (ctx : C.decls_ctx)
-    (region_groups : T.RegionGroupId.id list) (type_vars : T.type_var list)
-    (const_generic_vars : T.const_generic_var list) : C.eval_ctx =
-  C.reset_global_counters ();
+let initialize_eval_context (ctx : decls_ctx)
+    (region_groups : RegionGroupId.id list) (type_vars : type_var list)
+    (const_generic_vars : const_generic_var list) : eval_ctx =
+  reset_global_counters ();
   let const_generic_vars_map =
-    T.ConstGenericVarId.Map.of_list
+    ConstGenericVarId.Map.of_list
       (List.map
-         (fun (cg : T.const_generic_var) ->
-           let ty = TypesUtils.ety_no_regions_to_rty (T.Literal cg.ty) in
-           let cv = mk_fresh_symbolic_typed_value V.ConstGeneric ty in
+         (fun (cg : const_generic_var) ->
+           let ty = TLiteral cg.ty in
+           let cv = mk_fresh_symbolic_typed_value ConstGeneric ty in
            (cg.index, cv))
          const_generic_vars)
   in
   {
-    C.type_context = ctx.type_ctx;
-    C.fun_context = ctx.fun_ctx;
-    C.global_context = ctx.global_ctx;
-    C.trait_decls_context = ctx.trait_decls_ctx;
-    C.trait_impls_context = ctx.trait_impls_ctx;
-    C.region_groups;
-    C.type_vars;
-    C.const_generic_vars;
-    C.const_generic_vars_map;
-    C.norm_trait_etypes = C.ETraitTypeRefMap.empty (* Empty for now *);
-    C.norm_trait_rtypes = C.RTraitTypeRefMap.empty (* Empty for now *);
-    C.norm_trait_stypes = C.STraitTypeRefMap.empty (* Empty for now *);
-    C.env = [ C.Frame ];
-    C.ended_regions = T.RegionId.Set.empty;
+    type_context = ctx.type_ctx;
+    fun_context = ctx.fun_ctx;
+    global_context = ctx.global_ctx;
+    trait_decls_context = ctx.trait_decls_ctx;
+    trait_impls_context = ctx.trait_impls_ctx;
+    region_groups;
+    type_vars;
+    const_generic_vars;
+    const_generic_vars_map;
+    norm_trait_types = TraitTypeRefMap.empty (* Empty for now *);
+    env = [ EFrame ];
+    ended_regions = RegionId.Set.empty;
   }
 
 (** Instantiate a function signature, introducing **fresh** abstraction ids and
     region ids. This is mostly used in preparation of function calls (when
     evaluating in symbolic mode).
-
-    Note: there are no region parameters, because they should be erased.
  *)
-let instantiate_fun_sig (ctx : C.eval_ctx) (generics : T.egeneric_args)
-    (tr_self : T.rtrait_instance_id) (sg : A.fun_sig) : A.inst_fun_sig =
+let instantiate_fun_sig (ctx : eval_ctx) (generics : generic_args)
+    (tr_self : trait_instance_id) (sg : fun_sig)
+    (regions_hierarchy : region_groups) : inst_fun_sig =
   log#ldebug
     (lazy
       ("instantiate_fun_sig:" ^ "\n- generics: "
-      ^ egeneric_args_to_string ctx generics
+      ^ Print.EvalCtx.generic_args_to_string ctx generics
       ^ "\n- tr_self: "
-      ^ rtrait_instance_id_to_string ctx tr_self
+      ^ Print.EvalCtx.trait_instance_id_to_string ctx tr_self
       ^ "\n- sg: " ^ fun_sig_to_string ctx sg));
+  (* Erase the regions in the generics we use for the instantiation *)
+  let generics = Substitute.generic_args_erase_regions generics in
+  let tr_self = Substitute.trait_instance_id_erase_regions tr_self in
   (* Generate fresh abstraction ids and create a substitution from region
    * group ids to abstraction ids *)
   let rg_abs_ids_bindings =
     List.map
       (fun rg ->
-        let abs_id = C.fresh_abstraction_id () in
-        (rg.T.id, abs_id))
-      sg.regions_hierarchy
+        let abs_id = fresh_abstraction_id () in
+        (rg.id, abs_id))
+      regions_hierarchy
   in
-  let asubst_map : V.AbstractionId.id T.RegionGroupId.Map.t =
+  let asubst_map : AbstractionId.id RegionGroupId.Map.t =
     List.fold_left
-      (fun mp (rg_id, abs_id) -> T.RegionGroupId.Map.add rg_id abs_id mp)
-      T.RegionGroupId.Map.empty rg_abs_ids_bindings
+      (fun mp (rg_id, abs_id) -> RegionGroupId.Map.add rg_id abs_id mp)
+      RegionGroupId.Map.empty rg_abs_ids_bindings
   in
-  let asubst (rg_id : T.RegionGroupId.id) : V.AbstractionId.id =
-    T.RegionGroupId.Map.find rg_id asubst_map
+  let asubst (rg_id : RegionGroupId.id) : AbstractionId.id =
+    RegionGroupId.Map.find rg_id asubst_map
   in
   (* Generate fresh regions and their substitutions *)
-  let _, rsubst, _ = Subst.fresh_regions_with_substs sg.generics.regions in
+  let _, rsubst, _ = Substitute.fresh_regions_with_substs sg.generics.regions in
   (* Generate the type substitution
-   * Note that we need the substitution to map the type variables to
-   * {!rty} types (not {!ety}). In order to do that, we convert the
-   * type parameters to types with regions. This is possible only
-   * if those types don't contain any regions.
-   * This is a current limitation of the analysis: there is still some
-   * work to do to properly handle full type parametrization.
-   * *)
-  let rtype_params = List.map ety_no_regions_to_rty generics.types in
-  let tsubst = Subst.make_type_subst_from_vars sg.generics.types rtype_params in
+     Note that for now we don't support instantiating the type parameters with
+     types containing regions. *)
+  assert (List.for_all TypesUtils.ty_no_regions generics.types);
+  assert (TypesUtils.trait_instance_id_no_regions tr_self);
+  let tsubst =
+    Substitute.make_type_subst_from_vars sg.generics.types generics.types
+  in
   let cgsubst =
-    Subst.make_const_generic_subst_from_vars sg.generics.const_generics
+    Substitute.make_const_generic_subst_from_vars sg.generics.const_generics
       generics.const_generics
   in
-  (* TODO: something annoying with the trait ref subst: we need to use region
-     types, but the arguments use erased regions. For now we use the fact
-     that no regions should appear inside. In the future: we should merge
-     ety and rty. *)
-  let trait_refs =
-    List.map TypesUtils.etrait_ref_no_regions_to_gr_trait_ref
-      generics.trait_refs
-  in
   let tr_subst =
-    Subst.make_trait_subst_from_clauses sg.generics.trait_clauses trait_refs
+    Substitute.make_trait_subst_from_clauses sg.generics.trait_clauses
+      generics.trait_refs
   in
   (* Substitute the signature *)
   let inst_sig =
     AssociatedTypes.ctx_subst_norm_signature ctx asubst rsubst tsubst cgsubst
-      tr_subst tr_self sg
+      tr_subst tr_self sg regions_hierarchy
   in
   (* Return *)
   inst_sig
diff --git a/compiler/Invariants.ml b/compiler/Invariants.ml
index 5c8ec7af..e0e3f354 100644
--- a/compiler/Invariants.ml
+++ b/compiler/Invariants.ml
@@ -1,29 +1,23 @@
 (* The following module defines functions to check that some invariants
  * are always maintained by evaluation contexts *)
 
-module T = Types
-module PV = PrimitiveValues
-module V = Values
-module E = Expressions
-module C = Contexts
-module Subst = Substitute
-module Assoc = AssociatedTypes
-module A = LlbcAst
-module L = Logging
+open Types
+open Values
+open Contexts
 open Cps
 open TypesUtils
 open InterpreterUtils
 open InterpreterBorrowsCore
 
 (** The local logger *)
-let log = L.invariants_log
+let log = Logging.invariants_log
 
 type borrow_info = {
-  loan_kind : T.ref_kind;
+  loan_kind : ref_kind;
   loan_in_abs : bool;
   (* true if the loan was found in an abstraction *)
-  loan_ids : V.BorrowId.Set.t;
-  borrow_ids : V.BorrowId.Set.t;
+  loan_ids : BorrowId.Set.t;
+  borrow_ids : BorrowId.Set.t;
 }
 [@@deriving show]
 
@@ -39,30 +33,26 @@ let set_outer_mut (info : outer_borrow_info) : outer_borrow_info =
 let set_outer_shared (_info : outer_borrow_info) : outer_borrow_info =
   { outer_borrow = true; outer_shared = true }
 
-let ids_reprs_to_string (indent : string)
-    (reprs : V.BorrowId.id V.BorrowId.Map.t) : string =
-  V.BorrowId.Map.to_string (Some indent) V.BorrowId.to_string reprs
+let ids_reprs_to_string (indent : string) (reprs : BorrowId.id BorrowId.Map.t) :
+    string =
+  BorrowId.Map.to_string (Some indent) BorrowId.to_string reprs
 
 let borrows_infos_to_string (indent : string)
-    (infos : borrow_info V.BorrowId.Map.t) : string =
-  V.BorrowId.Map.to_string (Some indent) show_borrow_info infos
+    (infos : borrow_info BorrowId.Map.t) : string =
+  BorrowId.Map.to_string (Some indent) show_borrow_info infos
 
-type borrow_kind = Mut | Shared | Reserved
+type borrow_kind = BMut | BShared | BReserved
 
 (** Check that:
     - loans and borrows are correctly related
     - a two-phase borrow can't point to a value inside an abstraction
  *)
-let check_loans_borrows_relation_invariant (ctx : C.eval_ctx) : unit =
+let check_loans_borrows_relation_invariant (ctx : eval_ctx) : unit =
   (* Link all the borrow ids to a representant - necessary because of shared
    * borrows/loans *)
-  let ids_reprs : V.BorrowId.id V.BorrowId.Map.t ref =
-    ref V.BorrowId.Map.empty
-  in
+  let ids_reprs : BorrowId.id BorrowId.Map.t ref = ref BorrowId.Map.empty in
   (* Link all the id representants to a borrow information *)
-  let borrows_infos : borrow_info V.BorrowId.Map.t ref =
-    ref V.BorrowId.Map.empty
-  in
+  let borrows_infos : borrow_info BorrowId.Map.t ref = ref BorrowId.Map.empty in
   let context_to_string () : string =
     eval_ctx_to_string ctx ^ "- representants:\n"
     ^ ids_reprs_to_string "  " !ids_reprs
@@ -73,62 +63,61 @@ let check_loans_borrows_relation_invariant (ctx : C.eval_ctx) : unit =
    * map, we register it in this list; once the borrows_infos map is completely
    * built, we check that all the borrow ids of the ignored loans are in this
    * map *)
-  let ignored_loans : (T.ref_kind * V.BorrowId.id) list ref = ref [] in
+  let ignored_loans : (ref_kind * BorrowId.id) list ref = ref [] in
 
   (* first, register all the loans *)
   (* Some utilities to register the loans *)
-  let register_ignored_loan (rkind : T.ref_kind) (bid : V.BorrowId.id) : unit =
+  let register_ignored_loan (rkind : ref_kind) (bid : BorrowId.id) : unit =
     ignored_loans := (rkind, bid) :: !ignored_loans
   in
 
-  let register_shared_loan (loan_in_abs : bool) (bids : V.BorrowId.Set.t) : unit
-      =
+  let register_shared_loan (loan_in_abs : bool) (bids : BorrowId.Set.t) : unit =
     let reprs = !ids_reprs in
     let infos = !borrows_infos in
     (* Use the first borrow id as representant *)
-    let repr_bid = V.BorrowId.Set.min_elt bids in
-    assert (not (V.BorrowId.Map.mem repr_bid infos));
+    let repr_bid = BorrowId.Set.min_elt bids in
+    assert (not (BorrowId.Map.mem repr_bid infos));
     (* Insert the mappings to the representant *)
     let reprs =
-      V.BorrowId.Set.fold
+      BorrowId.Set.fold
         (fun bid reprs ->
-          assert (not (V.BorrowId.Map.mem bid reprs));
-          V.BorrowId.Map.add bid repr_bid reprs)
+          assert (not (BorrowId.Map.mem bid reprs));
+          BorrowId.Map.add bid repr_bid reprs)
         bids reprs
     in
     (* Insert the loan info *)
     let info =
       {
-        loan_kind = T.Shared;
+        loan_kind = RShared;
         loan_in_abs;
         loan_ids = bids;
-        borrow_ids = V.BorrowId.Set.empty;
+        borrow_ids = BorrowId.Set.empty;
       }
     in
-    let infos = V.BorrowId.Map.add repr_bid info infos in
+    let infos = BorrowId.Map.add repr_bid info infos in
     (* Update *)
     ids_reprs := reprs;
     borrows_infos := infos
   in
 
-  let register_mut_loan (loan_in_abs : bool) (bid : V.BorrowId.id) : unit =
+  let register_mut_loan (loan_in_abs : bool) (bid : BorrowId.id) : unit =
     let reprs = !ids_reprs in
     let infos = !borrows_infos in
     (* Sanity checks *)
-    assert (not (V.BorrowId.Map.mem bid reprs));
-    assert (not (V.BorrowId.Map.mem bid infos));
+    assert (not (BorrowId.Map.mem bid reprs));
+    assert (not (BorrowId.Map.mem bid infos));
     (* Add the mapping for the representant *)
-    let reprs = V.BorrowId.Map.add bid bid reprs in
+    let reprs = BorrowId.Map.add bid bid reprs in
     (* Add the mapping for the loan info *)
     let info =
       {
-        loan_kind = T.Mut;
+        loan_kind = RMut;
         loan_in_abs;
-        loan_ids = V.BorrowId.Set.singleton bid;
-        borrow_ids = V.BorrowId.Set.empty;
+        loan_ids = BorrowId.Set.singleton bid;
+        borrow_ids = BorrowId.Set.empty;
       }
     in
-    let infos = V.BorrowId.Map.add bid info infos in
+    let infos = BorrowId.Map.add bid info infos in
     (* Update *)
     ids_reprs := reprs;
     borrows_infos := infos
@@ -136,22 +125,22 @@ let check_loans_borrows_relation_invariant (ctx : C.eval_ctx) : unit =
 
   let loans_visitor =
     object
-      inherit [_] C.iter_eval_ctx as super
+      inherit [_] iter_eval_ctx as super
 
-      method! visit_Var _ binder v =
+      method! visit_EBinding _ binder v =
         let inside_abs = false in
-        super#visit_Var inside_abs binder v
+        super#visit_EBinding inside_abs binder v
 
-      method! visit_Abs _ abs =
+      method! visit_EAbs _ abs =
         let inside_abs = true in
-        super#visit_Abs inside_abs abs
+        super#visit_EAbs inside_abs abs
 
       method! visit_loan_content inside_abs lc =
         (* Register the loan *)
         let _ =
           match lc with
-          | V.SharedLoan (bids, _) -> register_shared_loan inside_abs bids
-          | V.MutLoan bid -> register_mut_loan inside_abs bid
+          | VSharedLoan (bids, _) -> register_shared_loan inside_abs bids
+          | VMutLoan bid -> register_mut_loan inside_abs bid
         in
         (* Continue exploring *)
         super#visit_loan_content inside_abs lc
@@ -159,14 +148,14 @@ let check_loans_borrows_relation_invariant (ctx : C.eval_ctx) : unit =
       method! visit_aloan_content inside_abs lc =
         let _ =
           match lc with
-          | V.AMutLoan (bid, _) -> register_mut_loan inside_abs bid
-          | V.ASharedLoan (bids, _, _) -> register_shared_loan inside_abs bids
-          | V.AIgnoredMutLoan (Some bid, _) -> register_ignored_loan T.Mut bid
-          | V.AIgnoredMutLoan (None, _)
-          | V.AIgnoredSharedLoan _
-          | V.AEndedMutLoan { given_back = _; child = _; given_back_meta = _ }
-          | V.AEndedSharedLoan (_, _)
-          | V.AEndedIgnoredMutLoan
+          | AMutLoan (bid, _) -> register_mut_loan inside_abs bid
+          | ASharedLoan (bids, _, _) -> register_shared_loan inside_abs bids
+          | AIgnoredMutLoan (Some bid, _) -> register_ignored_loan RMut bid
+          | AIgnoredMutLoan (None, _)
+          | AIgnoredSharedLoan _
+          | AEndedMutLoan { given_back = _; child = _; given_back_meta = _ }
+          | AEndedSharedLoan (_, _)
+          | AEndedIgnoredMutLoan
               { given_back = _; child = _; given_back_meta = _ } ->
               (* Do nothing *)
               ()
@@ -182,27 +171,27 @@ let check_loans_borrows_relation_invariant (ctx : C.eval_ctx) : unit =
 
   (* Then, register all the borrows *)
   (* Some utilities to register the borrows *)
-  let find_info (bid : V.BorrowId.id) : borrow_info =
+  let find_info (bid : BorrowId.id) : borrow_info =
     (* Find the representant *)
-    match V.BorrowId.Map.find_opt bid !ids_reprs with
+    match BorrowId.Map.find_opt bid !ids_reprs with
     | Some repr_bid ->
         (* Lookup the info *)
-        V.BorrowId.Map.find repr_bid !borrows_infos
+        BorrowId.Map.find repr_bid !borrows_infos
     | None ->
         let err =
           "find_info: could not find the representant of borrow "
-          ^ V.BorrowId.to_string bid ^ ":\nContext:\n" ^ context_to_string ()
+          ^ BorrowId.to_string bid ^ ":\nContext:\n" ^ context_to_string ()
         in
         log#serror err;
         raise (Failure err)
   in
 
-  let update_info (bid : V.BorrowId.id) (info : borrow_info) : unit =
+  let update_info (bid : BorrowId.id) (info : borrow_info) : unit =
     (* Find the representant *)
-    let repr_bid = V.BorrowId.Map.find bid !ids_reprs in
+    let repr_bid = BorrowId.Map.find bid !ids_reprs in
     (* Update the info *)
     let infos =
-      V.BorrowId.Map.update repr_bid
+      BorrowId.Map.update repr_bid
         (fun x ->
           match x with
           | Some _ -> Some info
@@ -214,39 +203,39 @@ let check_loans_borrows_relation_invariant (ctx : C.eval_ctx) : unit =
 
   let register_ignored_borrow = register_ignored_loan in
 
-  let register_borrow (kind : borrow_kind) (bid : V.BorrowId.id) : unit =
+  let register_borrow (kind : borrow_kind) (bid : BorrowId.id) : unit =
     (* Lookup the info *)
     let info = find_info bid in
     (* Check that the borrow kind is consistent *)
     (match (info.loan_kind, kind) with
-    | T.Shared, (Shared | Reserved) | T.Mut, Mut -> ()
+    | RShared, (BShared | BReserved) | RMut, BMut -> ()
     | _ -> raise (Failure "Invariant not satisfied"));
     (* A reserved borrow can't point to a value inside an abstraction *)
-    assert (kind <> Reserved || not info.loan_in_abs);
+    assert (kind <> BReserved || not info.loan_in_abs);
     (* Insert the borrow id *)
     let borrow_ids = info.borrow_ids in
-    assert (not (V.BorrowId.Set.mem bid borrow_ids));
-    let info = { info with borrow_ids = V.BorrowId.Set.add bid borrow_ids } in
+    assert (not (BorrowId.Set.mem bid borrow_ids));
+    let info = { info with borrow_ids = BorrowId.Set.add bid borrow_ids } in
     (* Update the info in the map *)
     update_info bid info
   in
 
   let borrows_visitor =
     object
-      inherit [_] C.iter_eval_ctx as super
+      inherit [_] iter_eval_ctx as super
 
       method! visit_abstract_shared_borrow _ asb =
         match asb with
-        | V.AsbBorrow bid -> register_borrow Shared bid
-        | V.AsbProjReborrows _ -> ()
+        | AsbBorrow bid -> register_borrow BShared bid
+        | AsbProjReborrows _ -> ()
 
       method! visit_borrow_content env bc =
         (* Register the loan *)
         let _ =
           match bc with
-          | V.SharedBorrow bid -> register_borrow Shared bid
-          | V.MutBorrow (bid, _) -> register_borrow Mut bid
-          | V.ReservedMutBorrow bid -> register_borrow Reserved bid
+          | VSharedBorrow bid -> register_borrow BShared bid
+          | VMutBorrow (bid, _) -> register_borrow BMut bid
+          | VReservedMutBorrow bid -> register_borrow BReserved bid
         in
         (* Continue exploring *)
         super#visit_borrow_content env bc
@@ -254,12 +243,12 @@ let check_loans_borrows_relation_invariant (ctx : C.eval_ctx) : unit =
       method! visit_aborrow_content env bc =
         let _ =
           match bc with
-          | V.AMutBorrow (bid, _) -> register_borrow Mut bid
-          | V.ASharedBorrow bid -> register_borrow Shared bid
-          | V.AIgnoredMutBorrow (Some bid, _) -> register_ignored_borrow Mut bid
-          | V.AIgnoredMutBorrow (None, _)
-          | V.AEndedMutBorrow _ | V.AEndedIgnoredMutBorrow _
-          | V.AEndedSharedBorrow | V.AProjSharedBorrow _ ->
+          | AMutBorrow (bid, _) -> register_borrow BMut bid
+          | ASharedBorrow bid -> register_borrow BShared bid
+          | AIgnoredMutBorrow (Some bid, _) -> register_ignored_borrow RMut bid
+          | AIgnoredMutBorrow (None, _)
+          | AEndedMutBorrow _ | AEndedIgnoredMutBorrow _ | AEndedSharedBorrow
+          | AProjSharedBorrow _ ->
               (* Do nothing *)
               ()
         in
@@ -284,28 +273,28 @@ let check_loans_borrows_relation_invariant (ctx : C.eval_ctx) : unit =
     !ignored_loans;
 
   (* Then, check the borrow infos *)
-  V.BorrowId.Map.iter
+  BorrowId.Map.iter
     (fun _ info ->
       (* Note that we can't directly compare the sets - I guess they are
        * different depending on the order in which we add the elements... *)
       assert (
-        V.BorrowId.Set.elements info.loan_ids
-        = V.BorrowId.Set.elements info.borrow_ids);
+        BorrowId.Set.elements info.loan_ids
+        = BorrowId.Set.elements info.borrow_ids);
       match info.loan_kind with
-      | T.Mut -> assert (V.BorrowId.Set.cardinal info.loan_ids = 1)
-      | T.Shared -> ())
+      | RMut -> assert (BorrowId.Set.cardinal info.loan_ids = 1)
+      | RShared -> ())
     !borrows_infos
 
 (** Check that:
     - borrows/loans can't contain ⊥ or reserved mut borrows
     - shared loans can't contain mutable loans
  *)
-let check_borrowed_values_invariant (ctx : C.eval_ctx) : unit =
+let check_borrowed_values_invariant (ctx : eval_ctx) : unit =
   let visitor =
     object
-      inherit [_] C.iter_eval_ctx as super
+      inherit [_] iter_eval_ctx as super
 
-      method! visit_Bottom info =
+      method! visit_VBottom info =
         (* No ⊥ inside borrowed values *)
         assert (Config.allow_bottom_below_borrow || not info.outer_borrow)
 
@@ -317,8 +306,8 @@ let check_borrowed_values_invariant (ctx : C.eval_ctx) : unit =
         (* Update the info *)
         let info =
           match lc with
-          | V.SharedLoan (_, _) -> set_outer_shared info
-          | V.MutLoan _ ->
+          | VSharedLoan (_, _) -> set_outer_shared info
+          | VMutLoan _ ->
               (* No mutable loan inside a shared loan *)
               assert (not info.outer_shared);
               set_outer_mut info
@@ -330,11 +319,11 @@ let check_borrowed_values_invariant (ctx : C.eval_ctx) : unit =
         (* Update the info *)
         let info =
           match bc with
-          | V.SharedBorrow _ -> set_outer_shared info
-          | V.ReservedMutBorrow _ ->
+          | VSharedBorrow _ -> set_outer_shared info
+          | VReservedMutBorrow _ ->
               assert (not info.outer_borrow);
               set_outer_shared info
-          | V.MutBorrow (_, _) -> set_outer_mut info
+          | VMutBorrow (_, _) -> set_outer_mut info
         in
         (* Continue exploring *)
         super#visit_borrow_content info bc
@@ -343,17 +332,16 @@ let check_borrowed_values_invariant (ctx : C.eval_ctx) : unit =
         (* Update the info *)
         let info =
           match lc with
-          | V.AMutLoan (_, _) -> set_outer_mut info
-          | V.ASharedLoan (_, _, _) -> set_outer_shared info
-          | V.AEndedMutLoan { given_back = _; child = _; given_back_meta = _ }
-            ->
+          | AMutLoan (_, _) -> set_outer_mut info
+          | ASharedLoan (_, _, _) -> set_outer_shared info
+          | AEndedMutLoan { given_back = _; child = _; given_back_meta = _ } ->
               set_outer_mut info
-          | V.AEndedSharedLoan (_, _) -> set_outer_shared info
-          | V.AIgnoredMutLoan (_, _) -> set_outer_mut info
-          | V.AEndedIgnoredMutLoan
+          | AEndedSharedLoan (_, _) -> set_outer_shared info
+          | AIgnoredMutLoan (_, _) -> set_outer_mut info
+          | AEndedIgnoredMutLoan
               { given_back = _; child = _; given_back_meta = _ } ->
               set_outer_mut info
-          | V.AIgnoredSharedLoan _ -> set_outer_shared info
+          | AIgnoredSharedLoan _ -> set_outer_shared info
         in
         (* Continue exploring *)
         super#visit_aloan_content info lc
@@ -362,12 +350,12 @@ let check_borrowed_values_invariant (ctx : C.eval_ctx) : unit =
         (* Update the info *)
         let info =
           match bc with
-          | V.AMutBorrow (_, _) -> set_outer_mut info
-          | V.ASharedBorrow _ | V.AEndedSharedBorrow -> set_outer_shared info
-          | V.AIgnoredMutBorrow _ | V.AEndedMutBorrow _
-          | V.AEndedIgnoredMutBorrow _ ->
+          | AMutBorrow (_, _) -> set_outer_mut info
+          | ASharedBorrow _ | AEndedSharedBorrow -> set_outer_shared info
+          | AIgnoredMutBorrow _ | AEndedMutBorrow _ | AEndedIgnoredMutBorrow _
+            ->
               set_outer_mut info
-          | V.AProjSharedBorrow _ -> set_outer_shared info
+          | AProjSharedBorrow _ -> set_outer_shared info
         in
         (* Continue exploring *)
         super#visit_aborrow_content info bc
@@ -378,130 +366,140 @@ let check_borrowed_values_invariant (ctx : C.eval_ctx) : unit =
   let info = { outer_borrow = false; outer_shared = false } in
   visitor#visit_eval_ctx info ctx
 
-let check_literal_type (cv : V.literal) (ty : PV.literal_type) : unit =
+let check_literal_type (cv : literal) (ty : literal_type) : unit =
   match (cv, ty) with
-  | PV.Scalar sv, PV.Integer int_ty -> assert (sv.int_ty = int_ty)
-  | PV.Bool _, PV.Bool | PV.Char _, PV.Char -> ()
+  | VScalar sv, TInteger int_ty -> assert (sv.int_ty = int_ty)
+  | VBool _, TBool | VChar _, TChar -> ()
   | _ -> raise (Failure "Erroneous typing")
 
-let check_typing_invariant (ctx : C.eval_ctx) : unit =
+let check_typing_invariant (ctx : eval_ctx) : unit =
   (* TODO: the type of aloans doens't make sense: they have a type
    * of the shape [& (mut) T] where they should have type [T]...
    * This messes a bit the type invariant checks when checking the
    * children. In order to isolate the problem (for future modifications)
-   * we introduce function, so that we can easily spot all the involved
+   * we introduce this function, so that we can easily spot all the involved
    * places.
    * *)
-  let aloan_get_expected_child_type (ty : 'r T.ty) : 'r T.ty =
+  let aloan_get_expected_child_type (ty : ty) : ty =
     let _, ty, _ = ty_get_ref ty in
     ty
   in
 
   let visitor =
     object
-      inherit [_] C.iter_eval_ctx as super
+      inherit [_] iter_eval_ctx as super
       method! visit_abs _ abs = super#visit_abs (Some abs) abs
 
+      method! visit_EBinding info binder v =
+        (* We also check that the regions are erased *)
+        assert (ty_is_ety v.ty);
+        super#visit_EBinding info binder v
+
+      method! visit_symbolic_value inside_abs v =
+        (* Check that the types have regions *)
+        assert (ty_is_rty v.sv_ty);
+        super#visit_symbolic_value inside_abs v
+
       method! visit_typed_value info tv =
+        (* Check that the types have erased regions *)
+        assert (ty_is_ety tv.ty);
         (* Check the current pair (value, type) *)
-        (match (tv.V.value, tv.V.ty) with
-        | V.Literal cv, T.Literal ty -> check_literal_type cv ty
+        (match (tv.value, tv.ty) with
+        | VLiteral cv, TLiteral ty -> check_literal_type cv ty
         (* ADT case *)
-        | V.Adt av, T.Adt (T.AdtId def_id, generics) ->
+        | VAdt av, TAdt (TAdtId def_id, generics) ->
             (* Retrieve the definition to check the variant id, the number of
              * parameters, etc. *)
-            let def = C.ctx_lookup_type_decl ctx def_id in
+            let def = ctx_lookup_type_decl ctx def_id in
             (* Check the number of parameters *)
             assert (
               List.length generics.regions = List.length def.generics.regions);
             assert (List.length generics.types = List.length def.generics.types);
             (* Check that the variant id is consistent *)
-            (match (av.V.variant_id, def.T.kind) with
-            | Some variant_id, T.Enum variants ->
-                assert (T.VariantId.to_int variant_id < List.length variants)
-            | None, T.Struct _ -> ()
+            (match (av.variant_id, def.kind) with
+            | Some variant_id, Enum variants ->
+                assert (VariantId.to_int variant_id < List.length variants)
+            | None, Struct _ -> ()
             | _ -> raise (Failure "Erroneous typing"));
             (* Check that the field types are correct *)
             let field_types =
-              Assoc.type_decl_get_inst_norm_field_etypes ctx def av.V.variant_id
-                generics
-            in
-            let fields_with_types =
-              List.combine av.V.field_values field_types
+              AssociatedTypes.type_decl_get_inst_norm_field_etypes ctx def
+                av.variant_id generics
             in
+            let fields_with_types = List.combine av.field_values field_types in
             List.iter
-              (fun ((v, ty) : V.typed_value * T.ety) -> assert (v.V.ty = ty))
+              (fun ((v, ty) : typed_value * ty) -> assert (v.ty = ty))
               fields_with_types
         (* Tuple case *)
-        | V.Adt av, T.Adt (T.Tuple, generics) ->
+        | VAdt av, TAdt (TTuple, generics) ->
             assert (generics.regions = []);
             assert (generics.const_generics = []);
-            assert (av.V.variant_id = None);
+            assert (av.variant_id = None);
             (* Check that the fields have the proper values - and check that there
              * are as many fields as field types at the same time *)
             let fields_with_types =
-              List.combine av.V.field_values generics.types
+              List.combine av.field_values generics.types
             in
             List.iter
-              (fun ((v, ty) : V.typed_value * T.ety) -> assert (v.V.ty = ty))
+              (fun ((v, ty) : typed_value * ty) -> assert (v.ty = ty))
               fields_with_types
         (* Assumed type case *)
-        | V.Adt av, T.Adt (T.Assumed aty_id, generics) -> (
-            assert (av.V.variant_id = None);
+        | VAdt av, TAdt (TAssumed aty_id, generics) -> (
+            assert (av.variant_id = None);
             match
               ( aty_id,
-                av.V.field_values,
+                av.field_values,
                 generics.regions,
                 generics.types,
                 generics.const_generics )
             with
             (* Box *)
-            | T.Box, [ inner_value ], [], [ inner_ty ], [] ->
-                assert (inner_value.V.ty = inner_ty)
-            | T.Array, inner_values, _, [ inner_ty ], [ cg ] ->
+            | TBox, [ inner_value ], [], [ inner_ty ], [] ->
+                assert (inner_value.ty = inner_ty)
+            | TArray, inner_values, _, [ inner_ty ], [ cg ] ->
                 (* *)
                 assert (
                   List.for_all
-                    (fun (v : V.typed_value) -> v.V.ty = inner_ty)
+                    (fun (v : typed_value) -> v.ty = inner_ty)
                     inner_values);
                 (* The length is necessarily concrete *)
                 let len =
-                  (PrimitiveValuesUtils.literal_as_scalar
+                  (ValuesUtils.literal_as_scalar
                      (TypesUtils.const_generic_as_literal cg))
                     .value
                 in
                 assert (Z.of_int (List.length inner_values) = len)
-            | (T.Slice | T.Str), _, _, _, _ -> raise (Failure "Unexpected")
+            | (TSlice | TStr), _, _, _, _ -> raise (Failure "Unexpected")
             | _ -> raise (Failure "Erroneous type"))
-        | V.Bottom, _ -> (* Nothing to check *) ()
-        | V.Borrow bc, T.Ref (_, ref_ty, rkind) -> (
+        | VBottom, _ -> (* Nothing to check *) ()
+        | VBorrow bc, TRef (_, ref_ty, rkind) -> (
             match (bc, rkind) with
-            | V.SharedBorrow bid, T.Shared | V.ReservedMutBorrow bid, T.Mut -> (
+            | VSharedBorrow bid, RShared | VReservedMutBorrow bid, RMut -> (
                 (* Lookup the borrowed value to check it has the proper type *)
                 let _, glc = lookup_loan ek_all bid ctx in
                 match glc with
-                | Concrete (V.SharedLoan (_, sv))
-                | Abstract (V.ASharedLoan (_, sv, _)) ->
-                    assert (sv.V.ty = ref_ty)
+                | Concrete (VSharedLoan (_, sv))
+                | Abstract (ASharedLoan (_, sv, _)) ->
+                    assert (sv.ty = ref_ty)
                 | _ -> raise (Failure "Inconsistent context"))
-            | V.MutBorrow (_, bv), T.Mut ->
+            | VMutBorrow (_, bv), RMut ->
                 assert (
                   (* Check that the borrowed value has the proper type *)
-                  bv.V.ty = ref_ty)
+                  bv.ty = ref_ty)
             | _ -> raise (Failure "Erroneous typing"))
-        | V.Loan lc, ty -> (
+        | VLoan lc, ty -> (
             match lc with
-            | V.SharedLoan (_, sv) -> assert (sv.V.ty = ty)
-            | V.MutLoan bid -> (
+            | VSharedLoan (_, sv) -> assert (sv.ty = ty)
+            | VMutLoan bid -> (
                 (* Lookup the borrowed value to check it has the proper type *)
                 let glc = lookup_borrow ek_all bid ctx in
                 match glc with
-                | Concrete (V.MutBorrow (_, bv)) -> assert (bv.V.ty = ty)
-                | Abstract (V.AMutBorrow (_, sv)) ->
-                    assert (Subst.erase_regions sv.V.ty = ty)
+                | Concrete (VMutBorrow (_, bv)) -> assert (bv.ty = ty)
+                | Abstract (AMutBorrow (_, sv)) ->
+                    assert (Substitute.erase_regions sv.ty = ty)
                 | _ -> raise (Failure "Inconsistent context")))
-        | V.Symbolic sv, ty ->
-            let ty' = Subst.erase_regions sv.V.sv_ty in
+        | VSymbolic sv, ty ->
+            let ty' = Substitute.erase_regions sv.sv_ty in
             assert (ty' = ty)
         | _ -> raise (Failure "Erroneous typing"));
         (* Continue exploring to inspect the subterms *)
@@ -516,13 +514,15 @@ let check_typing_invariant (ctx : C.eval_ctx) : unit =
        * so the cost of maintenance should be pretty low.
        * *)
       method! visit_typed_avalue info atv =
+        (* Check that the types have regions *)
+        assert (ty_is_rty atv.ty);
         (* Check the current pair (value, type) *)
-        (match (atv.V.value, atv.V.ty) with
+        (match (atv.value, atv.ty) with
         (* ADT case *)
-        | V.AAdt av, T.Adt (T.AdtId def_id, generics) ->
+        | AAdt av, TAdt (TAdtId def_id, generics) ->
             (* Retrieve the definition to check the variant id, the number of
              * parameters, etc. *)
-            let def = C.ctx_lookup_type_decl ctx def_id in
+            let def = ctx_lookup_type_decl ctx def_id in
             (* Check the number of parameters *)
             assert (
               List.length generics.regions = List.length def.generics.regions);
@@ -531,162 +531,153 @@ let check_typing_invariant (ctx : C.eval_ctx) : unit =
               List.length generics.const_generics
               = List.length def.generics.const_generics);
             (* Check that the variant id is consistent *)
-            (match (av.V.variant_id, def.T.kind) with
-            | Some variant_id, T.Enum variants ->
-                assert (T.VariantId.to_int variant_id < List.length variants)
-            | None, T.Struct _ -> ()
+            (match (av.variant_id, def.kind) with
+            | Some variant_id, Enum variants ->
+                assert (VariantId.to_int variant_id < List.length variants)
+            | None, Struct _ -> ()
             | _ -> raise (Failure "Erroneous typing"));
             (* Check that the field types are correct *)
             let field_types =
-              Assoc.type_decl_get_inst_norm_field_rtypes ctx def av.V.variant_id
-                generics
-            in
-            let fields_with_types =
-              List.combine av.V.field_values field_types
+              AssociatedTypes.type_decl_get_inst_norm_field_rtypes ctx def
+                av.variant_id generics
             in
+            let fields_with_types = List.combine av.field_values field_types in
             List.iter
-              (fun ((v, ty) : V.typed_avalue * T.rty) -> assert (v.V.ty = ty))
+              (fun ((v, ty) : typed_avalue * ty) -> assert (v.ty = ty))
               fields_with_types
         (* Tuple case *)
-        | V.AAdt av, T.Adt (T.Tuple, generics) ->
+        | AAdt av, TAdt (TTuple, generics) ->
             assert (generics.regions = []);
             assert (generics.const_generics = []);
-            assert (av.V.variant_id = None);
+            assert (av.variant_id = None);
             (* Check that the fields have the proper values - and check that there
              * are as many fields as field types at the same time *)
             let fields_with_types =
-              List.combine av.V.field_values generics.types
+              List.combine av.field_values generics.types
             in
             List.iter
-              (fun ((v, ty) : V.typed_avalue * T.rty) -> assert (v.V.ty = ty))
+              (fun ((v, ty) : typed_avalue * ty) -> assert (v.ty = ty))
               fields_with_types
         (* Assumed type case *)
-        | V.AAdt av, T.Adt (T.Assumed aty_id, generics) -> (
-            assert (av.V.variant_id = None);
+        | AAdt av, TAdt (TAssumed aty_id, generics) -> (
+            assert (av.variant_id = None);
             match
               ( aty_id,
-                av.V.field_values,
+                av.field_values,
                 generics.regions,
                 generics.types,
                 generics.const_generics )
             with
             (* Box *)
-            | T.Box, [ boxed_value ], [], [ boxed_ty ], [] ->
-                assert (boxed_value.V.ty = boxed_ty)
+            | TBox, [ boxed_value ], [], [ boxed_ty ], [] ->
+                assert (boxed_value.ty = boxed_ty)
             | _ -> raise (Failure "Erroneous type"))
-        | V.ABottom, _ -> (* Nothing to check *) ()
-        | V.ABorrow bc, T.Ref (_, ref_ty, rkind) -> (
+        | ABottom, _ -> (* Nothing to check *) ()
+        | ABorrow bc, TRef (_, ref_ty, rkind) -> (
             match (bc, rkind) with
-            | V.AMutBorrow (_, av), T.Mut ->
+            | AMutBorrow (_, av), RMut ->
                 (* Check that the child value has the proper type *)
-                assert (av.V.ty = ref_ty)
-            | V.ASharedBorrow bid, T.Shared -> (
+                assert (av.ty = ref_ty)
+            | ASharedBorrow bid, RShared -> (
                 (* Lookup the borrowed value to check it has the proper type *)
                 let _, glc = lookup_loan ek_all bid ctx in
                 match glc with
-                | Concrete (V.SharedLoan (_, sv))
-                | Abstract (V.ASharedLoan (_, sv, _)) ->
-                    assert (sv.V.ty = Subst.erase_regions ref_ty)
+                | Concrete (VSharedLoan (_, sv))
+                | Abstract (ASharedLoan (_, sv, _)) ->
+                    assert (sv.ty = Substitute.erase_regions ref_ty)
                 | _ -> raise (Failure "Inconsistent context"))
-            | V.AIgnoredMutBorrow (_opt_bid, av), T.Mut ->
-                assert (av.V.ty = ref_ty)
-            | ( V.AEndedIgnoredMutBorrow
-                  { given_back; child; given_back_meta = _ },
-                T.Mut ) ->
-                assert (given_back.V.ty = ref_ty);
-                assert (child.V.ty = ref_ty)
-            | V.AProjSharedBorrow _, T.Shared -> ()
+            | AIgnoredMutBorrow (_opt_bid, av), RMut -> assert (av.ty = ref_ty)
+            | ( AEndedIgnoredMutBorrow { given_back; child; given_back_meta = _ },
+                RMut ) ->
+                assert (given_back.ty = ref_ty);
+                assert (child.ty = ref_ty)
+            | AProjSharedBorrow _, RShared -> ()
             | _ -> raise (Failure "Inconsistent context"))
-        | V.ALoan lc, aty -> (
+        | ALoan lc, aty -> (
             match lc with
-            | V.AMutLoan (bid, child_av) | V.AIgnoredMutLoan (Some bid, child_av)
+            | AMutLoan (bid, child_av) | AIgnoredMutLoan (Some bid, child_av)
               -> (
                 let borrowed_aty = aloan_get_expected_child_type aty in
-                assert (child_av.V.ty = borrowed_aty);
+                assert (child_av.ty = borrowed_aty);
                 (* Lookup the borrowed value to check it has the proper type *)
                 let glc = lookup_borrow ek_all bid ctx in
                 match glc with
-                | Concrete (V.MutBorrow (_, bv)) ->
-                    assert (bv.V.ty = Subst.erase_regions borrowed_aty)
-                | Abstract (V.AMutBorrow (_, sv)) ->
+                | Concrete (VMutBorrow (_, bv)) ->
+                    assert (bv.ty = Substitute.erase_regions borrowed_aty)
+                | Abstract (AMutBorrow (_, sv)) ->
                     assert (
-                      Subst.erase_regions sv.V.ty
-                      = Subst.erase_regions borrowed_aty)
+                      Substitute.erase_regions sv.ty
+                      = Substitute.erase_regions borrowed_aty)
                 | _ -> raise (Failure "Inconsistent context"))
-            | V.AIgnoredMutLoan (None, child_av) ->
+            | AIgnoredMutLoan (None, child_av) ->
                 let borrowed_aty = aloan_get_expected_child_type aty in
-                assert (child_av.V.ty = borrowed_aty)
-            | V.ASharedLoan (_, sv, child_av) | V.AEndedSharedLoan (sv, child_av)
-              ->
+                assert (child_av.ty = borrowed_aty)
+            | ASharedLoan (_, sv, child_av) | AEndedSharedLoan (sv, child_av) ->
                 let borrowed_aty = aloan_get_expected_child_type aty in
-                assert (sv.V.ty = Subst.erase_regions borrowed_aty);
+                assert (sv.ty = Substitute.erase_regions borrowed_aty);
                 (* TODO: the type of aloans doesn't make sense, see above *)
-                assert (child_av.V.ty = borrowed_aty)
-            | V.AEndedMutLoan { given_back; child; given_back_meta = _ }
-            | V.AEndedIgnoredMutLoan { given_back; child; given_back_meta = _ }
-              ->
+                assert (child_av.ty = borrowed_aty)
+            | AEndedMutLoan { given_back; child; given_back_meta = _ }
+            | AEndedIgnoredMutLoan { given_back; child; given_back_meta = _ } ->
                 let borrowed_aty = aloan_get_expected_child_type aty in
-                assert (given_back.V.ty = borrowed_aty);
-                assert (child.V.ty = borrowed_aty)
-            | V.AIgnoredSharedLoan child_av ->
-                assert (child_av.V.ty = aloan_get_expected_child_type aty))
-        | V.ASymbolic aproj, ty -> (
-            let ty1 = Subst.erase_regions ty in
+                assert (given_back.ty = borrowed_aty);
+                assert (child.ty = borrowed_aty)
+            | AIgnoredSharedLoan child_av ->
+                assert (child_av.ty = aloan_get_expected_child_type aty))
+        | ASymbolic aproj, ty -> (
+            let ty1 = Substitute.erase_regions ty in
             match aproj with
-            | V.AProjLoans (sv, _) ->
-                let ty2 = Subst.erase_regions sv.V.sv_ty in
+            | AProjLoans (sv, _) ->
+                let ty2 = Substitute.erase_regions sv.sv_ty in
                 assert (ty1 = ty2);
                 (* Also check that the symbolic values contain regions of interest -
                  * otherwise they should have been reduced to [_] *)
                 let abs = Option.get info in
-                assert (ty_has_regions_in_set abs.regions sv.V.sv_ty)
-            | V.AProjBorrows (sv, proj_ty) ->
-                let ty2 = Subst.erase_regions sv.V.sv_ty in
+                assert (ty_has_regions_in_set abs.regions sv.sv_ty)
+            | AProjBorrows (sv, proj_ty) ->
+                let ty2 = Substitute.erase_regions sv.sv_ty in
                 assert (ty1 = ty2);
                 (* Also check that the symbolic values contain regions of interest -
                  * otherwise they should have been reduced to [_] *)
                 let abs = Option.get info in
                 assert (ty_has_regions_in_set abs.regions proj_ty)
-            | V.AEndedProjLoans (_msv, given_back_ls) ->
+            | AEndedProjLoans (_msv, given_back_ls) ->
                 List.iter
                   (fun (_, proj) ->
                     match proj with
-                    | V.AProjBorrows (_sv, ty') -> assert (ty' = ty)
-                    | V.AEndedProjBorrows _ | V.AIgnoredProjBorrows -> ()
+                    | AProjBorrows (_sv, ty') -> assert (ty' = ty)
+                    | AEndedProjBorrows _ | AIgnoredProjBorrows -> ()
                     | _ -> raise (Failure "Unexpected"))
                   given_back_ls
-            | V.AEndedProjBorrows _ | V.AIgnoredProjBorrows -> ())
-        | V.AIgnored, _ -> ()
+            | AEndedProjBorrows _ | AIgnoredProjBorrows -> ())
+        | AIgnored, _ -> ()
         | _ ->
             log#lerror
               (lazy
-                ("Erroneous typing:" ^ "\n- raw value: "
-               ^ V.show_typed_avalue atv ^ "\n- value: "
+                ("Erroneous typing:" ^ "\n- raw value: " ^ show_typed_avalue atv
+               ^ "\n- value: "
                 ^ typed_avalue_to_string ctx atv
-                ^ "\n- type: " ^ rty_to_string ctx atv.V.ty));
+                ^ "\n- type: " ^ ty_to_string ctx atv.ty));
             raise (Failure "Erroneous typing"));
         (* Continue exploring to inspect the subterms *)
         super#visit_typed_avalue info atv
     end
   in
-  visitor#visit_eval_ctx (None : V.abs option) ctx
+  visitor#visit_eval_ctx (None : abs option) ctx
 
 type proj_borrows_info = {
-  abs_id : V.AbstractionId.id;
-  regions : T.RegionId.Set.t;
-  proj_ty : T.rty;
+  abs_id : AbstractionId.id;
+  regions : RegionId.Set.t;
+  proj_ty : rty;  (** The regions shouldn't be erased *)
   as_shared_value : bool;  (** True if the value is below a shared borrow *)
 }
 [@@deriving show]
 
-type proj_loans_info = {
-  abs_id : V.AbstractionId.id;
-  regions : T.RegionId.Set.t;
-}
+type proj_loans_info = { abs_id : AbstractionId.id; regions : RegionId.Set.t }
 [@@deriving show]
 
 type sv_info = {
-  ty : T.rty;
+  ty : rty;  (** The regions shouldn't be erased *)
   env_count : int;
   aproj_borrows : proj_borrows_info list;
   aproj_loans : proj_loans_info list;
@@ -706,32 +697,32 @@ type sv_info = {
     - the union of the aproj_loans contains the aproj_borrows applied on the
       same symbolic values
  *)
-let check_symbolic_values (ctx : C.eval_ctx) : unit =
+let check_symbolic_values (ctx : eval_ctx) : unit =
   (* Small utility *)
-  let module M = V.SymbolicValueId.Map in
+  let module M = SymbolicValueId.Map in
   let infos : sv_info M.t ref = ref M.empty in
-  let lookup_info (sv : V.symbolic_value) : sv_info =
-    match M.find_opt sv.V.sv_id !infos with
+  let lookup_info (sv : symbolic_value) : sv_info =
+    match M.find_opt sv.sv_id !infos with
     | Some info -> info
     | None ->
         { ty = sv.sv_ty; env_count = 0; aproj_borrows = []; aproj_loans = [] }
   in
-  let update_info (sv : V.symbolic_value) (info : sv_info) =
+  let update_info (sv : symbolic_value) (info : sv_info) =
     infos := M.add sv.sv_id info !infos
   in
-  let add_env_sv (sv : V.symbolic_value) : unit =
+  let add_env_sv (sv : symbolic_value) : unit =
     let info = lookup_info sv in
     let info = { info with env_count = info.env_count + 1 } in
     update_info sv info
   in
-  let add_aproj_borrows (sv : V.symbolic_value) abs_id regions proj_ty
+  let add_aproj_borrows (sv : symbolic_value) abs_id regions proj_ty
       as_shared_value : unit =
     let info = lookup_info sv in
     let binfo = { abs_id; regions; proj_ty; as_shared_value } in
     let info = { info with aproj_borrows = binfo :: info.aproj_borrows } in
     update_info sv info
   in
-  let add_aproj_loans (sv : V.symbolic_value) abs_id regions : unit =
+  let add_aproj_loans (sv : symbolic_value) abs_id regions : unit =
     let info = lookup_info sv in
     let linfo = { abs_id; regions } in
     let info = { info with aproj_loans = linfo :: info.aproj_loans } in
@@ -740,14 +731,14 @@ let check_symbolic_values (ctx : C.eval_ctx) : unit =
   (* Visitor *)
   let obj =
     object
-      inherit [_] C.iter_eval_ctx as super
+      inherit [_] iter_eval_ctx as super
       method! visit_abs _ abs = super#visit_abs (Some abs) abs
-      method! visit_Symbolic _ sv = add_env_sv sv
+      method! visit_VSymbolic _ sv = add_env_sv sv
 
       method! visit_abstract_shared_borrow abs asb =
         let abs = Option.get abs in
         match asb with
-        | V.AsbBorrow _ -> ()
+        | AsbBorrow _ -> ()
         | AsbProjReborrows (sv, proj_ty) ->
             add_aproj_borrows sv abs.abs_id abs.regions proj_ty true
 
@@ -766,7 +757,7 @@ let check_symbolic_values (ctx : C.eval_ctx) : unit =
   log#ldebug
     (lazy
       ("check_symbolic_values: collected information:\n"
-      ^ V.SymbolicValueId.Map.to_string (Some "  ") show_sv_info !infos));
+      ^ SymbolicValueId.Map.to_string (Some "  ") show_sv_info !infos));
   (* Check *)
   let check_info _id info =
     (* TODO: check that:
@@ -792,14 +783,14 @@ let check_symbolic_values (ctx : C.eval_ctx) : unit =
       List.fold_left
         (fun regions linfo ->
           let regions =
-            T.RegionId.Set.fold
+            RegionId.Set.fold
               (fun rid regions ->
-                assert (not (T.RegionId.Set.mem rid regions));
-                T.RegionId.Set.add rid regions)
+                assert (not (RegionId.Set.mem rid regions));
+                RegionId.Set.add rid regions)
               regions linfo.regions
           in
           regions)
-        T.RegionId.Set.empty info.aproj_loans
+        RegionId.Set.empty info.aproj_loans
     in
     (* Check that the union of the loan projectors contains the borrow projections. *)
     List.iter
@@ -812,7 +803,7 @@ let check_symbolic_values (ctx : C.eval_ctx) : unit =
 
   M.iter check_info !infos
 
-let check_invariants (ctx : C.eval_ctx) : unit =
+let check_invariants (ctx : eval_ctx) : unit =
   if !Config.check_invariants then (
     log#ldebug (lazy ("Checking invariants:\n" ^ eval_ctx_to_string ctx));
     check_loans_borrows_relation_invariant ctx;
diff --git a/compiler/LlbcAst.ml b/compiler/LlbcAst.ml
index 2db859b2..9772671e 100644
--- a/compiler/LlbcAst.ml
+++ b/compiler/LlbcAst.ml
@@ -2,16 +2,13 @@ open Types
 open Values
 include Charon.LlbcAst
 
-type abs_region_group = (AbstractionId.id, RegionId.id) g_region_group
-[@@deriving show]
-
-type abs_region_groups = (AbstractionId.id, RegionId.id) g_region_groups
-[@@deriving show]
+type abs_region_group = AbstractionId.id g_region_group [@@deriving show]
+type abs_region_groups = abs_region_group list [@@deriving show]
 
 (** A function signature, after instantiation *)
 type inst_fun_sig = {
   regions_hierarchy : abs_region_groups;
-  trait_type_constraints : rtrait_type_constraint list;
+  trait_type_constraints : trait_type_constraint list;
   inputs : rty list;
   output : rty;
 }
diff --git a/compiler/LlbcAstUtils.ml b/compiler/LlbcAstUtils.ml
index 0ab4ed94..ffdce481 100644
--- a/compiler/LlbcAstUtils.ml
+++ b/compiler/LlbcAstUtils.ml
@@ -1,17 +1,25 @@
+open Types
 open LlbcAst
 include Charon.LlbcAstUtils
+open Collections
+
+module FunIdOrderedType : OrderedType with type t = fun_id = struct
+  type t = fun_id
+
+  let compare = compare_fun_id
+  let to_string = show_fun_id
+  let pp_t = pp_fun_id
+  let show_t = show_fun_id
+end
+
+module FunIdMap = Collections.MakeMap (FunIdOrderedType)
+module FunIdSet = Collections.MakeSet (FunIdOrderedType)
 
 let lookup_fun_sig (fun_id : fun_id) (fun_decls : fun_decl FunDeclId.Map.t) :
     fun_sig =
   match fun_id with
-  | Regular id -> (FunDeclId.Map.find id fun_decls).signature
-  | Assumed aid -> Assumed.get_assumed_fun_sig aid
-
-let lookup_fun_name (fun_id : fun_id) (fun_decls : fun_decl FunDeclId.Map.t) :
-    Names.fun_name =
-  match fun_id with
-  | Regular id -> (FunDeclId.Map.find id fun_decls).name
-  | Assumed aid -> Assumed.get_assumed_fun_name aid
+  | FRegular id -> (FunDeclId.Map.find id fun_decls).signature
+  | FAssumed aid -> Assumed.get_assumed_fun_sig aid
 
 (** Return the opaque declarations found in the crate, which are also *not builtin*.
 
@@ -21,27 +29,32 @@ let lookup_fun_name (fun_id : fun_id) (fun_decls : fun_decl FunDeclId.Map.t) :
     Remark: the list of functions also contains the list of opaque global bodies.
  *)
 let crate_get_opaque_non_builtin_decls (k : crate) (filter_assumed : bool) :
-    T.type_decl list * fun_decl list =
+    type_decl list * fun_decl list =
   let open ExtractBuiltin in
+  let ctx : Charon.NameMatcher.ctx =
+    {
+      type_decls = k.type_decls;
+      global_decls = k.global_decls;
+      trait_decls = k.trait_decls;
+    }
+  in
   let is_opaque_fun (d : fun_decl) : bool =
-    let sname = name_to_simple_name d.name in
     d.body = None
     (* Something to pay attention to: we must ignore trait method *declarations*
        (which don't have a body but must not be considered as opaque) *)
     && (match d.kind with TraitMethodDecl _ -> false | _ -> true)
     && ((not filter_assumed)
-       || (not (SimpleNameMap.mem sname builtin_globals_map))
-          && not (SimpleNameMap.mem sname (builtin_funs_map ())))
+       || (not (NameMatcherMap.mem ctx d.name builtin_globals_map))
+          && not (NameMatcherMap.mem ctx d.name (builtin_funs_map ())))
   in
-  let is_opaque_type (d : T.type_decl) : bool =
-    let sname = name_to_simple_name d.name in
-    d.kind = T.Opaque
+  let is_opaque_type (d : type_decl) : bool =
+    d.kind = Opaque
     && ((not filter_assumed)
-       || not (SimpleNameMap.mem sname (builtin_types_map ())))
+       || not (NameMatcherMap.mem ctx d.name (builtin_types_map ())))
   in
   (* Note that by checking the function bodies we also the globals *)
-  ( List.filter is_opaque_type (T.TypeDeclId.Map.values k.types),
-    List.filter is_opaque_fun (FunDeclId.Map.values k.functions) )
+  ( List.filter is_opaque_type (TypeDeclId.Map.values k.type_decls),
+    List.filter is_opaque_fun (FunDeclId.Map.values k.fun_decls) )
 
 (** Return true if the crate contains opaque declarations, ignoring the assumed
     definitions. *)
diff --git a/compiler/Logging.ml b/compiler/Logging.ml
index 721655b8..9c20f32f 100644
--- a/compiler/Logging.ml
+++ b/compiler/Logging.ml
@@ -6,6 +6,9 @@ include Charon.Logging
 (** Logger for PrePasses *)
 let pre_passes_log = L.get_logger "MainLogger.PrePasses"
 
+(** Logger for RegionsHierarchy *)
+let regions_hierarchy_log = L.get_logger "MainLogger.RegionsHierarchy"
+
 (** Logger for Translate *)
 let translate_log = L.get_logger "MainLogger.Translate"
 
@@ -24,6 +27,9 @@ let pure_micro_passes_log = L.get_logger "MainLogger.PureMicroPasses"
 (** Logger for ExtractBase *)
 let extract_log = L.get_logger "MainLogger.ExtractBase"
 
+(** Logger for ExtractBuiltin *)
+let builtin_log = L.get_logger "MainLogger.Builtin"
+
 (** Logger for Interpreter *)
 let interpreter_log = L.get_logger "MainLogger.Interpreter"
 
diff --git a/compiler/Driver.ml b/compiler/Main.ml
index 128ae890..e350da8a 100644
--- a/compiler/Driver.ml
+++ b/compiler/Main.ml
@@ -1,15 +1,10 @@
 open Aeneas.LlbcOfJson
 open Aeneas.Logging
-module T = Aeneas.Types
-module A = Aeneas.LlbcAst
-module I = Aeneas.Interpreter
+open Aeneas.LlbcAst
+open Aeneas.Interpreter
 module EL = Easy_logging.Logging
-module TA = Aeneas.TypesAnalysis
-module Micro = Aeneas.PureMicroPasses
-module Print = Aeneas.Print
-module PrePasses = Aeneas.PrePasses
-module Translate = Aeneas.Translate
 open Aeneas.Config
+open Aeneas
 
 (** The local logger *)
 let log = main_log
@@ -23,6 +18,7 @@ let _ =
   Easy_logging.Handlers.set_level main_logger_handler EL.Debug;
   main_log#set_level EL.Info;
   llbc_of_json_logger#set_level EL.Info;
+  regions_hierarchy_log#set_level EL.Info;
   pre_passes_log#set_level EL.Info;
   associated_types_log#set_level EL.Info;
   contexts_log#set_level EL.Info;
@@ -42,6 +38,7 @@ let _ =
   symbolic_to_pure_log#set_level EL.Info;
   pure_micro_passes_log#set_level EL.Info;
   extract_log#set_level EL.Info;
+  builtin_log#set_level EL.Info;
   translate_log#set_level EL.Info;
   scc_log#set_level EL.Info;
   reorder_decls_log#set_level EL.Info
@@ -181,7 +178,10 @@ let () =
           log#error "The Lean backend doesn't support the -use-fuel option";
           fail ());
         (* Lean can disambiguate the field names *)
-        record_fields_short_names := true
+        record_fields_short_names := true;
+        (* We exploit the fact that the variant name should always be
+           prefixed with the type name to prevent collisions *)
+        variant_concatenate_type_name := false
     | HOL4 ->
         (* We don't support fuel for the HOL4 backend *)
         if !use_fuel then (
@@ -226,7 +226,9 @@ let () =
       if
         !backend = Lean && !extract_decreases_clauses
         && List.exists
-             (function Aeneas.LlbcAst.Fun (Rec (_ :: _)) -> true | _ -> false)
+             (function
+               | Aeneas.LlbcAst.FunGroup (RecGroup (_ :: _)) -> true
+               | _ -> false)
              m.declarations
       then (
         log#error
@@ -236,15 +238,15 @@ let () =
         fail ());
 
       (* Apply the pre-passes *)
-      let m = PrePasses.apply_passes m in
+      let m = Aeneas.PrePasses.apply_passes m in
 
       (* Some options for the execution *)
 
       (* Test the unit functions with the concrete interpreter *)
-      if !test_unit_functions then I.Test.test_unit_functions m;
+      if !test_unit_functions then Test.test_unit_functions m;
 
       (* Translate the functions *)
-      Translate.translate_crate filename dest_dir m;
+      Aeneas.Translate.translate_crate filename dest_dir m;
 
       (* Print total elapsed time *)
       log#linfo
diff --git a/compiler/Names.ml b/compiler/Names.ml
deleted file mode 100644
index 97dbc180..00000000
--- a/compiler/Names.ml
+++ /dev/null
@@ -1 +0,0 @@
-include Charon.Names
diff --git a/compiler/PrePasses.ml b/compiler/PrePasses.ml
index ee06fa07..c6b098e6 100644
--- a/compiler/PrePasses.ml
+++ b/compiler/PrePasses.ml
@@ -2,16 +2,13 @@
     (concrete/symbolic) interpreter on it
  *)
 
-module T = Types
-module V = Values
-module E = Expressions
-module C = Contexts
-module A = LlbcAst
-module L = Logging
+open Types
+open Expressions
+open LlbcAst
 open Utils
 open LlbcAstUtils
 
-let log = L.pre_passes_log
+let log = Logging.pre_passes_log
 
 (** Rustc inserts a lot of drops before the assignments.
 
@@ -27,11 +24,11 @@ let log = L.pre_passes_log
 
     Rem.: we don't use this anymore
  *)
-let filter_drop_assigns (f : A.fun_decl) : A.fun_decl =
+let filter_drop_assigns (f : fun_decl) : fun_decl =
   (* The visitor *)
   let obj =
     object (self)
-      inherit [_] A.map_statement as super
+      inherit [_] map_statement as super
 
       method! visit_Sequence env st1 st2 =
         match (st1.content, st2.content) with
@@ -91,7 +88,7 @@ let filter_drop_assigns (f : A.fun_decl) : A.fun_decl =
       restrictions on the rvalue), fake reads, drops (usually, returns will be
       followed by such statements)
  *)
-let remove_useless_cf_merges (crate : A.crate) (f : A.fun_decl) : A.fun_decl =
+let remove_useless_cf_merges (crate : crate) (f : fun_decl) : fun_decl =
   let f0 = f in
   (* Return [true] if the statement can be moved inside the branches of a switch.
    *
@@ -99,8 +96,7 @@ let remove_useless_cf_merges (crate : A.crate) (f : A.fun_decl) : A.fun_decl =
    * (inside the encountered sequences) don't need to end with [return] or [panic],
    * but all the paths inside the whole statement have to.
    * *)
-  let rec can_be_moved_aux (must_end_with_exit : bool) (st : A.statement) : bool
-      =
+  let rec can_be_moved_aux (must_end_with_exit : bool) (st : statement) : bool =
     match st.content with
     | SetDiscriminant _ | Assert _ | Call _ | Break _ | Continue _ | Switch _
     | Loop _ ->
@@ -108,7 +104,7 @@ let remove_useless_cf_merges (crate : A.crate) (f : A.fun_decl) : A.fun_decl =
     | Assign (_, rv) -> (
         match rv with
         | Use _ | RvRef _ -> not must_end_with_exit
-        | Aggregate (AggregatedAdt (Tuple, _, _), []) -> not must_end_with_exit
+        | Aggregate (AggregatedAdt (TTuple, _, _), []) -> not must_end_with_exit
         | _ -> false)
     | FakeRead _ | Drop _ | Nop -> not must_end_with_exit
     | Panic | Return -> true
@@ -120,7 +116,7 @@ let remove_useless_cf_merges (crate : A.crate) (f : A.fun_decl) : A.fun_decl =
   (* The visitor *)
   let obj =
     object
-      inherit [_] A.map_statement as super
+      inherit [_] map_statement as super
 
       method! visit_Sequence env st1 st2 =
         match st1.content with
@@ -189,14 +185,14 @@ let remove_useless_cf_merges (crate : A.crate) (f : A.fun_decl) : A.fun_decl =
       };
     ]}
  *)
-let remove_loop_breaks (crate : A.crate) (f : A.fun_decl) : A.fun_decl =
+let remove_loop_breaks (crate : crate) (f : fun_decl) : fun_decl =
   let f0 = f in
 
   (* Check that a statement doesn't contain loops, breaks or continues *)
-  let statement_has_no_loop_break_continue (st : A.statement) : bool =
+  let statement_has_no_loop_break_continue (st : statement) : bool =
     let obj =
       object
-        inherit [_] A.iter_statement
+        inherit [_] iter_statement
         method! visit_Loop _ _ = raise Found
         method! visit_Break _ _ = raise Found
         method! visit_Continue _ _ = raise Found
@@ -212,10 +208,10 @@ let remove_loop_breaks (crate : A.crate) (f : A.fun_decl) : A.fun_decl =
      break statement breaks exactly one level, and that there are no nested
      loops.
   *)
-  let replace_breaks_with (st : A.statement) (nst : A.statement) : A.statement =
+  let replace_breaks_with (st : statement) (nst : statement) : statement =
     let obj =
       object
-        inherit [_] A.map_statement as super
+        inherit [_] map_statement as super
 
         method! visit_Loop entered_loop loop =
           assert (not entered_loop);
@@ -232,7 +228,7 @@ let remove_loop_breaks (crate : A.crate) (f : A.fun_decl) : A.fun_decl =
   (* The visitor *)
   let obj =
     object
-      inherit [_] A.map_statement as super
+      inherit [_] map_statement as super
 
       method! visit_Sequence env st1 st2 =
         match st1.content with
@@ -365,27 +361,27 @@ let remove_loop_breaks (crate : A.crate) (f : A.fun_decl) : A.fun_decl =
     We then check that [x] completely disappeared from the function body (for
     sanity).
  *)
-let remove_shallow_borrows (crate : A.crate) (f : A.fun_decl) : A.fun_decl =
+let remove_shallow_borrows (crate : crate) (f : fun_decl) : fun_decl =
   let f0 = f in
-  let filter_in_body (body : A.statement) : A.statement =
-    let filtered = ref E.VarId.Set.empty in
+  let filter_in_body (body : statement) : statement =
+    let filtered = ref VarId.Set.empty in
 
     let filter_visitor =
       object
-        inherit [_] A.map_statement as super
+        inherit [_] map_statement as super
 
         method! visit_Assign env p rv =
           match (p.projection, rv) with
-          | [], E.RvRef (_, E.Shallow) ->
+          | [], RvRef (_, BShallow) ->
               (* Filter *)
-              filtered := E.VarId.Set.add p.var_id !filtered;
+              filtered := VarId.Set.add p.var_id !filtered;
               Nop
           | _ ->
               (* Don't filter *)
               super#visit_Assign env p rv
 
         method! visit_FakeRead env p =
-          if p.projection = [] && E.VarId.Set.mem p.var_id !filtered then
+          if p.projection = [] && VarId.Set.mem p.var_id !filtered then
             (* Filter *)
             Nop
           else super#visit_FakeRead env p
@@ -398,8 +394,8 @@ let remove_shallow_borrows (crate : A.crate) (f : A.fun_decl) : A.fun_decl =
     (* Check that the filtered variables completely disappeared from the body *)
     let check_visitor =
       object
-        inherit [_] A.iter_statement
-        method! visit_var_id _ id = assert (not (E.VarId.Set.mem id !filtered))
+        inherit [_] iter_statement
+        method! visit_var_id _ id = assert (not (VarId.Set.mem id !filtered))
       end
     in
     check_visitor#visit_statement () body;
@@ -423,14 +419,14 @@ let remove_shallow_borrows (crate : A.crate) (f : A.fun_decl) : A.fun_decl =
       ^ "\n"));
   f
 
-let apply_passes (crate : A.crate) : A.crate =
+let apply_passes (crate : crate) : crate =
   let passes = [ remove_loop_breaks crate; remove_shallow_borrows crate ] in
-  let functions =
+  let fun_decls =
     List.fold_left
-      (fun fl pass -> A.FunDeclId.Map.map pass fl)
-      crate.functions passes
+      (fun fl pass -> FunDeclId.Map.map pass fl)
+      crate.fun_decls passes
   in
-  let crate = { crate with functions } in
+  let crate = { crate with fun_decls } in
   log#ldebug
     (lazy ("After pre-passes:\n" ^ Print.Crate.crate_to_string crate ^ "\n"));
   crate
diff --git a/compiler/PrimitiveValues.ml b/compiler/PrimitiveValues.ml
deleted file mode 100644
index 0eacca9e..00000000
--- a/compiler/PrimitiveValues.ml
+++ /dev/null
@@ -1 +0,0 @@
-include Charon.PrimitiveValues
diff --git a/compiler/PrimitiveValuesUtils.ml b/compiler/PrimitiveValuesUtils.ml
deleted file mode 100644
index 0000916d..00000000
--- a/compiler/PrimitiveValuesUtils.ml
+++ /dev/null
@@ -1 +0,0 @@
-include Charon.PrimitiveValuesUtils
diff --git a/compiler/Print.ml b/compiler/Print.ml
index 7f0d95ff..92ce6f23 100644
--- a/compiler/Print.ml
+++ b/compiler/Print.ml
@@ -1,9 +1,15 @@
 include Charon.PrintUtils
 include Charon.PrintLlbcAst
-module V = Values
-module VU = ValuesUtils
-module C = Contexts
-module PrimitiveValues = Charon.PrintPrimitiveValues
+open Charon.PrintTypes
+open Charon.PrintExpressions
+open Charon.PrintLlbcAst.Ast
+open Types
+open TypesUtils
+open Values
+open ValuesUtils
+open Expressions
+open LlbcAst
+open Contexts
 module Types = Charon.PrintTypes
 module Expressions = Charon.PrintExpressions
 
@@ -14,102 +20,44 @@ let bool_to_string (b : bool) : string = if b then "true" else "false"
 
 (** Pretty-printing for values *)
 module Values = struct
-  type value_formatter = {
-    rvar_to_string : T.RegionVarId.id -> string;
-    r_to_string : T.RegionId.id -> string;
-    type_var_id_to_string : T.TypeVarId.id -> string;
-    type_decl_id_to_string : T.TypeDeclId.id -> string;
-    const_generic_var_id_to_string : T.ConstGenericVarId.id -> string;
-    global_decl_id_to_string : T.GlobalDeclId.id -> string;
-    trait_decl_id_to_string : T.TraitDeclId.id -> string;
-    trait_impl_id_to_string : T.TraitImplId.id -> string;
-    trait_clause_id_to_string : T.TraitClauseId.id -> string;
-    adt_variant_to_string : T.TypeDeclId.id -> T.VariantId.id -> string;
-    var_id_to_string : E.VarId.id -> string;
-    adt_field_names :
-      T.TypeDeclId.id -> T.VariantId.id option -> string list option;
-  }
-
-  let value_to_etype_formatter (fmt : value_formatter) : PT.etype_formatter =
-    {
-      PT.r_to_string = PT.erased_region_to_string;
-      PT.type_var_id_to_string = fmt.type_var_id_to_string;
-      PT.type_decl_id_to_string = fmt.type_decl_id_to_string;
-      PT.const_generic_var_id_to_string = fmt.const_generic_var_id_to_string;
-      PT.global_decl_id_to_string = fmt.global_decl_id_to_string;
-      PT.trait_decl_id_to_string = fmt.trait_decl_id_to_string;
-      PT.trait_impl_id_to_string = fmt.trait_impl_id_to_string;
-      PT.trait_clause_id_to_string = fmt.trait_clause_id_to_string;
-    }
-
-  let value_to_rtype_formatter (fmt : value_formatter) : PT.rtype_formatter =
-    {
-      PT.r_to_string = PT.region_to_string fmt.r_to_string;
-      PT.type_var_id_to_string = fmt.type_var_id_to_string;
-      PT.type_decl_id_to_string = fmt.type_decl_id_to_string;
-      PT.const_generic_var_id_to_string = fmt.const_generic_var_id_to_string;
-      PT.global_decl_id_to_string = fmt.global_decl_id_to_string;
-      PT.trait_decl_id_to_string = fmt.trait_decl_id_to_string;
-      PT.trait_impl_id_to_string = fmt.trait_impl_id_to_string;
-      PT.trait_clause_id_to_string = fmt.trait_clause_id_to_string;
-    }
-
-  let value_to_stype_formatter (fmt : value_formatter) : PT.stype_formatter =
-    {
-      PT.r_to_string = PT.region_to_string fmt.rvar_to_string;
-      PT.type_var_id_to_string = fmt.type_var_id_to_string;
-      PT.type_decl_id_to_string = fmt.type_decl_id_to_string;
-      PT.const_generic_var_id_to_string = fmt.const_generic_var_id_to_string;
-      PT.global_decl_id_to_string = fmt.global_decl_id_to_string;
-      PT.trait_decl_id_to_string = fmt.trait_decl_id_to_string;
-      PT.trait_impl_id_to_string = fmt.trait_impl_id_to_string;
-      PT.trait_clause_id_to_string = fmt.trait_clause_id_to_string;
-    }
-
-  let var_id_to_string (id : E.VarId.id) : string =
-    "var@" ^ E.VarId.to_string id
+  include Charon.PrintValues
 
-  let symbolic_value_id_to_string (id : V.SymbolicValueId.id) : string =
-    "s@" ^ V.SymbolicValueId.to_string id
+  let symbolic_value_id_to_pretty_string (id : SymbolicValueId.id) : string =
+    "s@" ^ SymbolicValueId.to_string id
 
-  let symbolic_value_to_string (fmt : PT.rtype_formatter)
-      (sv : V.symbolic_value) : string =
-    symbolic_value_id_to_string sv.sv_id ^ " : " ^ PT.rty_to_string fmt sv.sv_ty
+  let symbolic_value_to_string (env : fmt_env) (sv : symbolic_value) : string =
+    symbolic_value_id_to_pretty_string sv.sv_id
+    ^ " : " ^ ty_to_string env sv.sv_ty
 
-  let symbolic_value_proj_to_string (fmt : value_formatter)
-      (sv : V.symbolic_value) (rty : T.rty) : string =
-    symbolic_value_id_to_string sv.sv_id
-    ^ " : "
-    ^ PT.ty_to_string (value_to_rtype_formatter fmt) sv.sv_ty
-    ^ " <: "
-    ^ PT.ty_to_string (value_to_rtype_formatter fmt) rty
+  let symbolic_value_proj_to_string (env : fmt_env) (sv : symbolic_value)
+      (rty : ty) : string =
+    symbolic_value_id_to_pretty_string sv.sv_id
+    ^ " : " ^ ty_to_string env sv.sv_ty ^ " <: " ^ ty_to_string env rty
 
   (* TODO: it may be a good idea to try to factorize this function with
    * typed_avalue_to_string. At some point we had done it, because [typed_value]
    * and [typed_avalue] were instances of the same general type [g_typed_value],
    * but then we removed this general type because it proved to be a bad idea. *)
-  let rec typed_value_to_string (fmt : value_formatter) (v : V.typed_value) :
-      string =
-    let ty_fmt : PT.etype_formatter = value_to_etype_formatter fmt in
+  let rec typed_value_to_string (env : fmt_env) (v : typed_value) : string =
     match v.value with
-    | Literal cv -> PPV.literal_to_string cv
-    | Adt av -> (
+    | VLiteral cv -> literal_to_string cv
+    | VAdt av -> (
         let field_values =
-          List.map (typed_value_to_string fmt) av.field_values
+          List.map (typed_value_to_string env) av.field_values
         in
         match v.ty with
-        | T.Adt (T.Tuple, _) ->
+        | TAdt (TTuple, _) ->
             (* Tuple *)
             "(" ^ String.concat ", " field_values ^ ")"
-        | T.Adt (T.AdtId def_id, _) ->
+        | TAdt (TAdtId def_id, _) ->
             (* "Regular" ADT *)
             let adt_ident =
               match av.variant_id with
-              | Some vid -> fmt.adt_variant_to_string def_id vid
-              | None -> fmt.type_decl_id_to_string def_id
+              | Some vid -> adt_variant_to_string env def_id vid
+              | None -> type_decl_id_to_string env def_id
             in
             if List.length field_values > 0 then
-              match fmt.adt_field_names def_id av.V.variant_id with
+              match adt_field_names env def_id av.variant_id with
               | None ->
                   let field_values = String.concat ", " field_values in
                   adt_ident ^ " (" ^ field_values ^ ")"
@@ -123,97 +71,91 @@ module Values = struct
                   let field_values = String.concat " " field_values in
                   adt_ident ^ " { " ^ field_values ^ " }"
             else adt_ident
-        | T.Adt (T.Assumed aty, _) -> (
+        | TAdt (TAssumed aty, _) -> (
             (* Assumed type *)
             match (aty, field_values) with
-            | Box, [ bv ] -> "@Box(" ^ bv ^ ")"
-            | Array, _ ->
+            | TBox, [ bv ] -> "@Box(" ^ bv ^ ")"
+            | TArray, _ ->
                 (* Happens when we aggregate values *)
                 "@Array[" ^ String.concat ", " field_values ^ "]"
-            | _ ->
-                raise (Failure ("Inconsistent value: " ^ V.show_typed_value v)))
+            | _ -> raise (Failure ("Inconsistent value: " ^ show_typed_value v))
+            )
         | _ -> raise (Failure "Inconsistent typed value"))
-    | Bottom -> "⊥ : " ^ PT.ty_to_string ty_fmt v.ty
-    | Borrow bc -> borrow_content_to_string fmt bc
-    | Loan lc -> loan_content_to_string fmt lc
-    | Symbolic s -> symbolic_value_to_string (value_to_rtype_formatter fmt) s
+    | VBottom -> "⊥ : " ^ ty_to_string env v.ty
+    | VBorrow bc -> borrow_content_to_string env bc
+    | VLoan lc -> loan_content_to_string env lc
+    | VSymbolic s -> symbolic_value_to_string env s
 
-  and borrow_content_to_string (fmt : value_formatter) (bc : V.borrow_content) :
-      string =
+  and borrow_content_to_string (env : fmt_env) (bc : borrow_content) : string =
     match bc with
-    | SharedBorrow bid -> "⌊shared@" ^ V.BorrowId.to_string bid ^ "⌋"
-    | MutBorrow (bid, tv) ->
-        "&mut@" ^ V.BorrowId.to_string bid ^ " ("
-        ^ typed_value_to_string fmt tv
+    | VSharedBorrow bid -> "⌊shared@" ^ BorrowId.to_string bid ^ "⌋"
+    | VMutBorrow (bid, tv) ->
+        "&mut@" ^ BorrowId.to_string bid ^ " ("
+        ^ typed_value_to_string env tv
         ^ ")"
-    | ReservedMutBorrow bid -> "⌊reserved_mut@" ^ V.BorrowId.to_string bid ^ "⌋"
+    | VReservedMutBorrow bid -> "⌊reserved_mut@" ^ BorrowId.to_string bid ^ "⌋"
 
-  and loan_content_to_string (fmt : value_formatter) (lc : V.loan_content) :
-      string =
+  and loan_content_to_string (env : fmt_env) (lc : loan_content) : string =
     match lc with
-    | SharedLoan (loans, v) ->
-        let loans = V.BorrowId.Set.to_string None loans in
-        "@shared_loan(" ^ loans ^ ", " ^ typed_value_to_string fmt v ^ ")"
-    | MutLoan bid -> "⌊mut@" ^ V.BorrowId.to_string bid ^ "⌋"
+    | VSharedLoan (loans, v) ->
+        let loans = BorrowId.Set.to_string None loans in
+        "@shared_loan(" ^ loans ^ ", " ^ typed_value_to_string env v ^ ")"
+    | VMutLoan bid -> "⌊mut@" ^ BorrowId.to_string bid ^ "⌋"
 
-  let abstract_shared_borrow_to_string (fmt : value_formatter)
-      (abs : V.abstract_shared_borrow) : string =
+  let abstract_shared_borrow_to_string (env : fmt_env)
+      (abs : abstract_shared_borrow) : string =
     match abs with
-    | AsbBorrow bid -> V.BorrowId.to_string bid
+    | AsbBorrow bid -> BorrowId.to_string bid
     | AsbProjReborrows (sv, rty) ->
-        "{" ^ symbolic_value_proj_to_string fmt sv rty ^ "}"
+        "{" ^ symbolic_value_proj_to_string env sv rty ^ "}"
 
-  let abstract_shared_borrows_to_string (fmt : value_formatter)
-      (abs : V.abstract_shared_borrows) : string =
+  let abstract_shared_borrows_to_string (env : fmt_env)
+      (abs : abstract_shared_borrows) : string =
     "{"
-    ^ String.concat "," (List.map (abstract_shared_borrow_to_string fmt) abs)
+    ^ String.concat "," (List.map (abstract_shared_borrow_to_string env) abs)
     ^ "}"
 
-  let rec aproj_to_string (fmt : value_formatter) (pv : V.aproj) : string =
+  let rec aproj_to_string (env : fmt_env) (pv : aproj) : string =
     match pv with
     | AProjLoans (sv, given_back) ->
         let given_back =
           if given_back = [] then ""
           else
             let given_back = List.map snd given_back in
-            let given_back = List.map (aproj_to_string fmt) given_back in
+            let given_back = List.map (aproj_to_string env) given_back in
             " (" ^ String.concat "," given_back ^ ") "
         in
-        "⌊"
-        ^ symbolic_value_to_string (value_to_rtype_formatter fmt) sv
-        ^ given_back ^ "⌋"
+        "⌊" ^ symbolic_value_to_string env sv ^ given_back ^ "⌋"
     | AProjBorrows (sv, rty) ->
-        "(" ^ symbolic_value_proj_to_string fmt sv rty ^ ")"
+        "(" ^ symbolic_value_proj_to_string env sv rty ^ ")"
     | AEndedProjLoans (_, given_back) ->
         if given_back = [] then "_"
         else
           let given_back = List.map snd given_back in
-          let given_back = List.map (aproj_to_string fmt) given_back in
+          let given_back = List.map (aproj_to_string env) given_back in
           "ended_aproj_loans (" ^ String.concat "," given_back ^ ")"
     | AEndedProjBorrows _mv -> "_"
     | AIgnoredProjBorrows -> "_"
 
-  let rec typed_avalue_to_string (fmt : value_formatter) (v : V.typed_avalue) :
-      string =
-    let ty_fmt : PT.rtype_formatter = value_to_rtype_formatter fmt in
+  let rec typed_avalue_to_string (env : fmt_env) (v : typed_avalue) : string =
     match v.value with
     | AAdt av -> (
         let field_values =
-          List.map (typed_avalue_to_string fmt) av.field_values
+          List.map (typed_avalue_to_string env) av.field_values
         in
         match v.ty with
-        | T.Adt (T.Tuple, _) ->
+        | TAdt (TTuple, _) ->
             (* Tuple *)
             "(" ^ String.concat ", " field_values ^ ")"
-        | T.Adt (T.AdtId def_id, _) ->
+        | TAdt (TAdtId def_id, _) ->
             (* "Regular" ADT *)
             let adt_ident =
               match av.variant_id with
-              | Some vid -> fmt.adt_variant_to_string def_id vid
-              | None -> fmt.type_decl_id_to_string def_id
+              | Some vid -> adt_variant_to_string env def_id vid
+              | None -> type_decl_id_to_string env def_id
             in
             if List.length field_values > 0 then
-              match fmt.adt_field_names def_id av.V.variant_id with
+              match adt_field_names env def_id av.variant_id with
               | None ->
                   let field_values = String.concat ", " field_values in
                   adt_ident ^ " (" ^ field_values ^ ")"
@@ -227,133 +169,130 @@ module Values = struct
                   let field_values = String.concat " " field_values in
                   adt_ident ^ " { " ^ field_values ^ " }"
             else adt_ident
-        | T.Adt (T.Assumed aty, _) -> (
+        | TAdt (TAssumed aty, _) -> (
             (* Assumed type *)
             match (aty, field_values) with
-            | Box, [ bv ] -> "@Box(" ^ bv ^ ")"
+            | TBox, [ bv ] -> "@Box(" ^ bv ^ ")"
             | _ -> raise (Failure "Inconsistent value"))
         | _ -> raise (Failure "Inconsistent typed value"))
-    | ABottom -> "⊥ : " ^ PT.ty_to_string ty_fmt v.ty
-    | ABorrow bc -> aborrow_content_to_string fmt bc
-    | ALoan lc -> aloan_content_to_string fmt lc
-    | ASymbolic s -> aproj_to_string fmt s
+    | ABottom -> "⊥ : " ^ ty_to_string env v.ty
+    | ABorrow bc -> aborrow_content_to_string env bc
+    | ALoan lc -> aloan_content_to_string env lc
+    | ASymbolic s -> aproj_to_string env s
     | AIgnored -> "_"
 
-  and aloan_content_to_string (fmt : value_formatter) (lc : V.aloan_content) :
-      string =
+  and aloan_content_to_string (env : fmt_env) (lc : aloan_content) : string =
     match lc with
     | AMutLoan (bid, av) ->
-        "⌊mut@" ^ V.BorrowId.to_string bid ^ ", "
-        ^ typed_avalue_to_string fmt av
+        "⌊mut@" ^ BorrowId.to_string bid ^ ", "
+        ^ typed_avalue_to_string env av
         ^ "⌋"
     | ASharedLoan (loans, v, av) ->
-        let loans = V.BorrowId.Set.to_string None loans in
+        let loans = BorrowId.Set.to_string None loans in
         "@shared_loan(" ^ loans ^ ", "
-        ^ typed_value_to_string fmt v
+        ^ typed_value_to_string env v
         ^ ", "
-        ^ typed_avalue_to_string fmt av
+        ^ typed_avalue_to_string env av
         ^ ")"
     | AEndedMutLoan ml ->
         "@ended_mut_loan{"
-        ^ typed_avalue_to_string fmt ml.child
+        ^ typed_avalue_to_string env ml.child
         ^ "; "
-        ^ typed_avalue_to_string fmt ml.given_back
+        ^ typed_avalue_to_string env ml.given_back
         ^ " }"
     | AEndedSharedLoan (v, av) ->
         "@ended_shared_loan("
-        ^ typed_value_to_string fmt v
+        ^ typed_value_to_string env v
         ^ ", "
-        ^ typed_avalue_to_string fmt av
+        ^ typed_avalue_to_string env av
         ^ ")"
     | AIgnoredMutLoan (opt_bid, av) ->
         "@ignored_mut_loan("
-        ^ option_to_string V.BorrowId.to_string opt_bid
+        ^ option_to_string BorrowId.to_string opt_bid
         ^ ", "
-        ^ typed_avalue_to_string fmt av
+        ^ typed_avalue_to_string env av
         ^ ")"
     | AEndedIgnoredMutLoan ml ->
         "@ended_ignored_mut_loan{ "
-        ^ typed_avalue_to_string fmt ml.child
+        ^ typed_avalue_to_string env ml.child
         ^ "; "
-        ^ typed_avalue_to_string fmt ml.given_back
+        ^ typed_avalue_to_string env ml.given_back
         ^ "}"
     | AIgnoredSharedLoan sl ->
-        "@ignored_shared_loan(" ^ typed_avalue_to_string fmt sl ^ ")"
+        "@ignored_shared_loan(" ^ typed_avalue_to_string env sl ^ ")"
 
-  and aborrow_content_to_string (fmt : value_formatter) (bc : V.aborrow_content)
-      : string =
+  and aborrow_content_to_string (env : fmt_env) (bc : aborrow_content) : string
+      =
     match bc with
     | AMutBorrow (bid, av) ->
-        "&mut@" ^ V.BorrowId.to_string bid ^ " ("
-        ^ typed_avalue_to_string fmt av
+        "&mut@" ^ BorrowId.to_string bid ^ " ("
+        ^ typed_avalue_to_string env av
         ^ ")"
-    | ASharedBorrow bid -> "⌊shared@" ^ V.BorrowId.to_string bid ^ "⌋"
+    | ASharedBorrow bid -> "⌊shared@" ^ BorrowId.to_string bid ^ "⌋"
     | AIgnoredMutBorrow (opt_bid, av) ->
         "@ignored_mut_borrow("
-        ^ option_to_string V.BorrowId.to_string opt_bid
+        ^ option_to_string BorrowId.to_string opt_bid
         ^ ", "
-        ^ typed_avalue_to_string fmt av
+        ^ typed_avalue_to_string env av
         ^ ")"
     | AEndedMutBorrow (_mv, child) ->
-        "@ended_mut_borrow(" ^ typed_avalue_to_string fmt child ^ ")"
+        "@ended_mut_borrow(" ^ typed_avalue_to_string env child ^ ")"
     | AEndedIgnoredMutBorrow { child; given_back; given_back_meta = _ } ->
         "@ended_ignored_mut_borrow{ "
-        ^ typed_avalue_to_string fmt child
+        ^ typed_avalue_to_string env child
         ^ "; "
-        ^ typed_avalue_to_string fmt given_back
+        ^ typed_avalue_to_string env given_back
         ^ ")"
     | AEndedSharedBorrow -> "@ended_shared_borrow"
     | AProjSharedBorrow sb ->
         "@ignored_shared_borrow("
-        ^ abstract_shared_borrows_to_string fmt sb
+        ^ abstract_shared_borrows_to_string env sb
         ^ ")"
 
-  let loop_abs_kind_to_string (kind : V.loop_abs_kind) : string =
+  let loop_abs_kind_to_string (kind : loop_abs_kind) : string =
     match kind with
     | LoopSynthInput -> "LoopSynthInput"
     | LoopCall -> "LoopCall"
 
-  let abs_kind_to_string (kind : V.abs_kind) : string =
+  let abs_kind_to_string (kind : abs_kind) : string =
     match kind with
-    | V.FunCall (fid, rg_id) ->
-        "FunCall(fid:" ^ V.FunCallId.to_string fid ^ ", rg_id:"
-        ^ T.RegionGroupId.to_string rg_id
+    | FunCall (fid, rg_id) ->
+        "FunCall(fid:" ^ FunCallId.to_string fid ^ ", rg_id:"
+        ^ RegionGroupId.to_string rg_id
         ^ ")"
     | SynthInput rg_id ->
-        "SynthInput(rg_id:" ^ T.RegionGroupId.to_string rg_id ^ ")"
-    | SynthRet rg_id ->
-        "SynthRet(rg_id:" ^ T.RegionGroupId.to_string rg_id ^ ")"
+        "SynthInput(rg_id:" ^ RegionGroupId.to_string rg_id ^ ")"
+    | SynthRet rg_id -> "SynthRet(rg_id:" ^ RegionGroupId.to_string rg_id ^ ")"
     | Loop (lp_id, rg_id, abs_kind) ->
-        "Loop(loop_id:" ^ V.LoopId.to_string lp_id ^ ", rg_id:"
-        ^ option_to_string T.RegionGroupId.to_string rg_id
+        "Loop(loop_id:" ^ LoopId.to_string lp_id ^ ", rg_id:"
+        ^ option_to_string RegionGroupId.to_string rg_id
         ^ ", loop abs kind: "
         ^ loop_abs_kind_to_string abs_kind
         ^ ")"
     | Identity -> "Identity"
 
-  let abs_to_string (fmt : value_formatter) (verbose : bool) (indent : string)
-      (indent_incr : string) (abs : V.abs) : string =
+  let abs_to_string (env : fmt_env) (verbose : bool) (indent : string)
+      (indent_incr : string) (abs : abs) : string =
     let indent2 = indent ^ indent_incr in
     let avs =
-      List.map (fun av -> indent2 ^ typed_avalue_to_string fmt av) abs.avalues
+      List.map (fun av -> indent2 ^ typed_avalue_to_string env av) abs.avalues
     in
     let avs = String.concat ",\n" avs in
     let kind =
       if verbose then "[kind:" ^ abs_kind_to_string abs.kind ^ "]" else ""
     in
     indent ^ "abs@"
-    ^ V.AbstractionId.to_string abs.abs_id
+    ^ AbstractionId.to_string abs.abs_id
     ^ kind ^ "{parents="
-    ^ V.AbstractionId.Set.to_string None abs.parents
+    ^ AbstractionId.Set.to_string None abs.parents
     ^ "}" ^ "{regions="
-    ^ T.RegionId.Set.to_string None abs.regions
+    ^ RegionId.Set.to_string None abs.regions
     ^ "}" ^ " {\n" ^ avs ^ "\n" ^ indent ^ "}"
 
-  let inst_fun_sig_to_string (fmt : value_formatter) (sg : LlbcAst.inst_fun_sig)
-      : string =
+  let inst_fun_sig_to_string (env : fmt_env) (sg : LlbcAst.inst_fun_sig) :
+      string =
     (* TODO: print the trait type constraints? *)
-    let ty_fmt = value_to_rtype_formatter fmt in
-    let ty_to_string = PT.ty_to_string ty_fmt in
+    let ty_to_string = ty_to_string env in
 
     let inputs =
       "(" ^ String.concat ", " (List.map ty_to_string sg.inputs) ^ ")"
@@ -362,71 +301,67 @@ module Values = struct
     inputs ^ " -> " ^ output
 end
 
-module PV = Values (* local module *)
-
 (** Pretty-printing for contexts *)
 module Contexts = struct
-  let var_binder_to_string (bv : C.var_binder) : string =
+  open Values
+
+  let var_binder_to_string (env : fmt_env) (bv : var_binder) : string =
     match bv.name with
-    | None -> PV.var_id_to_string bv.index
-    | Some name -> name ^ "^" ^ E.VarId.to_string bv.index
+    | None -> var_id_to_string env bv.index
+    | Some name -> name ^ "^" ^ VarId.to_string bv.index
 
-  let dummy_var_id_to_string (bid : C.DummyVarId.id) : string =
-    "_@" ^ C.DummyVarId.to_string bid
+  let dummy_var_id_to_string (bid : DummyVarId.id) : string =
+    "_@" ^ DummyVarId.to_string bid
 
-  let binder_to_string (bv : C.binder) : string =
+  let binder_to_string (env : fmt_env) (bv : binder) : string =
     match bv with
-    | VarBinder b -> var_binder_to_string b
-    | DummyBinder bid -> dummy_var_id_to_string bid
+    | BVar b -> var_binder_to_string env b
+    | BDummy bid -> dummy_var_id_to_string bid
 
-  let env_elem_to_string (fmt : PV.value_formatter) (verbose : bool)
+  let env_elem_to_string (env : fmt_env) (verbose : bool)
       (with_var_types : bool) (indent : string) (indent_incr : string)
-      (ev : C.env_elem) : string =
+      (ev : env_elem) : string =
     match ev with
-    | Var (var, tv) ->
-        let bv = binder_to_string var in
+    | EBinding (var, tv) ->
+        let bv = binder_to_string env var in
         let ty =
-          if with_var_types then
-            " : " ^ PT.ty_to_string (PV.value_to_etype_formatter fmt) tv.V.ty
-          else ""
+          if with_var_types then " : " ^ ty_to_string env tv.ty else ""
         in
-        indent ^ bv ^ ty ^ " -> " ^ PV.typed_value_to_string fmt tv ^ " ;"
-    | Abs abs -> PV.abs_to_string fmt verbose indent indent_incr abs
-    | Frame -> raise (Failure "Can't print a Frame element")
+        indent ^ bv ^ ty ^ " -> " ^ typed_value_to_string env tv ^ " ;"
+    | EAbs abs -> abs_to_string env verbose indent indent_incr abs
+    | EFrame -> raise (Failure "Can't print a Frame element")
 
-  let opt_env_elem_to_string (fmt : PV.value_formatter) (verbose : bool)
+  let opt_env_elem_to_string (env : fmt_env) (verbose : bool)
       (with_var_types : bool) (indent : string) (indent_incr : string)
-      (ev : C.env_elem option) : string =
+      (ev : env_elem option) : string =
     match ev with
     | None -> indent ^ "..."
     | Some ev ->
-        env_elem_to_string fmt verbose with_var_types indent indent_incr ev
+        env_elem_to_string env verbose with_var_types indent indent_incr ev
 
   (** Filters "dummy" bindings from an environment, to gain space and clarity/
       See [env_to_string]. *)
-  let filter_env (env : C.env) : C.env_elem option list =
+  let filter_env (env : env) : env_elem option list =
     (* We filter:
      * - non-dummy bindings which point to ⊥
      * - dummy bindings which don't contain loans nor borrows
      * Note that the first case can sometimes be confusing: we may try to improve
      * it...
      *)
-    let filter_elem (ev : C.env_elem) : C.env_elem option =
+    let filter_elem (ev : env_elem) : env_elem option =
       match ev with
-      | Var (VarBinder _, tv) ->
+      | EBinding (BVar _, tv) ->
           (* Not a dummy binding: check if the value is ⊥ *)
-          if VU.is_bottom tv.value then None else Some ev
-      | Var (DummyBinder _, tv) ->
+          if is_bottom tv.value then None else Some ev
+      | EBinding (BDummy _, tv) ->
           (* Dummy binding: check if the value contains borrows or loans *)
-          if VU.borrows_in_value tv || VU.loans_in_value tv then Some ev
-          else None
+          if borrows_in_value tv || loans_in_value tv then Some ev else None
       | _ -> Some ev
     in
     let env = List.map filter_elem env in
     (* We collapse groups of filtered values - so that we can print one
      * single "..." for a whole group of filtered values *)
-    let rec group_filtered (env : C.env_elem option list) :
-        C.env_elem option list =
+    let rec group_filtered (env : env_elem option list) : env_elem option list =
       match env with
       | [] -> []
       | None :: None :: env -> group_filtered (None :: env)
@@ -439,8 +374,8 @@ module Contexts = struct
       "..." to gain space and clarity.
       [with_var_types]: if true, print the type of the variables
    *)
-  let env_to_string (filter : bool) (fmt : PV.value_formatter) (verbose : bool)
-      (with_var_types : bool) (env : C.env) : string =
+  let env_to_string (filter : bool) (fmt_env : fmt_env) (verbose : bool)
+      (with_var_types : bool) (env : env) : string =
     let env =
       if filter then filter_env env else List.map (fun ev -> Some ev) env
     in
@@ -448,138 +383,70 @@ module Contexts = struct
     ^ String.concat "\n"
         (List.map
            (fun ev ->
-             opt_env_elem_to_string fmt verbose with_var_types "  " "  " ev)
+             opt_env_elem_to_string fmt_env verbose with_var_types "  " "  " ev)
            env)
     ^ "\n}"
 
-  type ctx_formatter = PV.value_formatter
-
-  let ast_to_ctx_formatter (fmt : PA.ast_formatter) : ctx_formatter =
-    {
-      PV.rvar_to_string = fmt.rvar_to_string;
-      PV.r_to_string = fmt.r_to_string;
-      PV.type_var_id_to_string = fmt.type_var_id_to_string;
-      PV.type_decl_id_to_string = fmt.type_decl_id_to_string;
-      PV.const_generic_var_id_to_string = fmt.const_generic_var_id_to_string;
-      PV.global_decl_id_to_string = fmt.global_decl_id_to_string;
-      PV.adt_variant_to_string = fmt.adt_variant_to_string;
-      PV.var_id_to_string = fmt.var_id_to_string;
-      PV.adt_field_names = fmt.adt_field_names;
-      PV.trait_decl_id_to_string = fmt.trait_decl_id_to_string;
-      PV.trait_impl_id_to_string = fmt.trait_impl_id_to_string;
-      PV.trait_clause_id_to_string = fmt.trait_clause_id_to_string;
-    }
-
-  let ast_to_value_formatter (fmt : PA.ast_formatter) : PV.value_formatter =
-    ast_to_ctx_formatter fmt
-
-  let ctx_to_etype_formatter (fmt : ctx_formatter) : PT.etype_formatter =
-    PV.value_to_etype_formatter fmt
-
-  let ctx_to_rtype_formatter (fmt : ctx_formatter) : PT.rtype_formatter =
-    PV.value_to_rtype_formatter fmt
-
-  let ctx_to_stype_formatter (fmt : ctx_formatter) : PT.stype_formatter =
-    PV.value_to_stype_formatter fmt
-
-  let eval_ctx_to_ctx_formatter (ctx : C.eval_ctx) : ctx_formatter =
-    let rvar_to_string r =
-      (* In theory we shouldn't use rvar_to_string, but it can happen
-         when printing definitions for instance... *)
-      T.RegionVarId.to_string r
-    in
-    let r_to_string r = PT.region_id_to_string r in
-
-    let type_var_id_to_string vid =
-      (* The context may be invalid *)
-      match C.lookup_type_var_opt ctx vid with
-      | None -> T.TypeVarId.to_string vid
-      | Some v -> v.name
-    in
-    let const_generic_var_id_to_string vid =
-      match C.lookup_const_generic_var_opt ctx vid with
-      | None -> T.ConstGenericVarId.to_string vid
-      | Some v -> v.name
-    in
-    let type_decl_id_to_string def_id =
-      let def = C.ctx_lookup_type_decl ctx def_id in
-      name_to_string def.name
-    in
-    let global_decl_id_to_string def_id =
-      let def = C.ctx_lookup_global_decl ctx def_id in
-      name_to_string def.name
-    in
-    let trait_decl_id_to_string def_id =
-      let def = C.ctx_lookup_trait_decl ctx def_id in
-      name_to_string def.name
-    in
-    let trait_impl_id_to_string def_id =
-      let def = C.ctx_lookup_trait_impl ctx def_id in
-      name_to_string def.name
-    in
-    let trait_clause_id_to_string id = PT.trait_clause_id_to_pretty_string id in
-    let adt_variant_to_string =
-      PT.type_ctx_to_adt_variant_to_string_fun ctx.type_context.type_decls
-    in
-    let var_id_to_string vid =
-      let bv = C.ctx_lookup_var_binder ctx vid in
-      var_binder_to_string bv
-    in
-    let adt_field_names =
-      PT.type_ctx_to_adt_field_names_fun ctx.type_context.type_decls
-    in
+  let decls_ctx_to_fmt_env (ctx : decls_ctx) : fmt_env =
+    let type_decls = ctx.type_ctx.type_decls in
+    let fun_decls = ctx.fun_ctx.fun_decls in
+    let global_decls = ctx.global_ctx.global_decls in
+    let trait_decls = ctx.trait_decls_ctx.trait_decls in
+    let trait_impls = ctx.trait_impls_ctx.trait_impls in
+    let generics = TypesUtils.empty_generic_params in
+    let preds = TypesUtils.empty_predicates in
     {
-      rvar_to_string;
-      r_to_string;
-      type_var_id_to_string;
-      type_decl_id_to_string;
-      const_generic_var_id_to_string;
-      global_decl_id_to_string;
-      adt_variant_to_string;
-      var_id_to_string;
-      adt_field_names;
-      trait_decl_id_to_string;
-      trait_impl_id_to_string;
-      trait_clause_id_to_string;
+      type_decls;
+      fun_decls;
+      global_decls;
+      trait_decls;
+      trait_impls;
+      generics;
+      preds;
+      locals = [];
     }
 
-  let eval_ctx_to_ast_formatter (ctx : C.eval_ctx) : PA.ast_formatter =
-    let ctx_fmt = eval_ctx_to_ctx_formatter ctx in
-    let adt_field_to_string =
-      PT.type_ctx_to_adt_field_to_string_fun ctx.type_context.type_decls
-    in
-    let fun_decl_id_to_string def_id =
-      let def = C.ctx_lookup_fun_decl ctx def_id in
-      fun_name_to_string def.name
+  let eval_ctx_to_fmt_env (ctx : eval_ctx) : fmt_env =
+    let type_decls = ctx.type_context.type_decls in
+    let fun_decls = ctx.fun_context.fun_decls in
+    let global_decls = ctx.global_context.global_decls in
+    let trait_decls = ctx.trait_decls_context.trait_decls in
+    let trait_impls = ctx.trait_impls_context.trait_impls in
+    (* Below: it is always safe to omit fields - if an id can't be found at
+       printing time, we print the id (in raw form) instead of the name it
+       designates. *)
+    let generics : generic_params =
+      {
+        types = ctx.type_vars;
+        (* The regions have been transformed to region groups *)
+        regions = [];
+        const_generics = ctx.const_generic_vars;
+        (* We don't need the trait clauses so we initialize them to empty *)
+        trait_clauses = [];
+      }
     in
-    let global_decl_id_to_string def_id =
-      let def = C.ctx_lookup_global_decl ctx def_id in
-      global_name_to_string def.name
-    in
-    let trait_decl_id_to_string def_id =
-      let def = C.ctx_lookup_trait_decl ctx def_id in
-      name_to_string def.name
-    in
-    let trait_impl_id_to_string def_id =
-      let def = C.ctx_lookup_trait_impl ctx def_id in
-      name_to_string def.name
+    (* We don't need the predicates so we initialize them to empty *)
+    let preds = empty_predicates in
+    (* For the locals: we retrieve the information from the environment.
+       Note that the locals don't need to be ordered based on their indices.
+    *)
+    let rec env_to_locals (env : env) : (VarId.id * string option) list =
+      match env with
+      | [] | EFrame :: _ -> []
+      | EAbs _ :: env -> env_to_locals env
+      | EBinding (BVar b, _) :: env -> (b.index, b.name) :: env_to_locals env
+      | EBinding (BDummy _, _) :: env -> env_to_locals env
     in
-    let trait_clause_id_to_string id = PT.trait_clause_id_to_pretty_string id in
+    let locals = env_to_locals ctx.env in
     {
-      rvar_to_string = ctx_fmt.PV.rvar_to_string;
-      r_to_string = ctx_fmt.PV.r_to_string;
-      type_var_id_to_string = ctx_fmt.PV.type_var_id_to_string;
-      type_decl_id_to_string = ctx_fmt.PV.type_decl_id_to_string;
-      const_generic_var_id_to_string = ctx_fmt.PV.const_generic_var_id_to_string;
-      adt_variant_to_string = ctx_fmt.PV.adt_variant_to_string;
-      var_id_to_string = ctx_fmt.PV.var_id_to_string;
-      adt_field_names = ctx_fmt.PV.adt_field_names;
-      adt_field_to_string;
-      fun_decl_id_to_string;
-      global_decl_id_to_string;
-      trait_decl_id_to_string;
-      trait_impl_id_to_string;
-      trait_clause_id_to_string;
+      type_decls;
+      fun_decls;
+      global_decls;
+      trait_decls;
+      trait_impls;
+      generics;
+      preds;
+      locals;
     }
 
   (** Split an [env] at every occurrence of [Frame], eliminating those elements.
@@ -588,20 +455,21 @@ module Contexts = struct
           * frames: from the current frame to the first pushed (oldest frame)
           * values: from the first pushed (oldest) to the last pushed
        *)
-  let split_env_according_to_frames (env : C.env) : C.env list =
-    let rec split_aux (frames : C.env list) (curr_frame : C.env) (env : C.env) =
+  let split_env_according_to_frames (env : env) : env list =
+    let rec split_aux (frames : env list) (curr_frame : env) (env : env) =
       match env with
       | [] ->
           if List.length curr_frame > 0 then curr_frame :: frames else frames
-      | Frame :: env' -> split_aux (curr_frame :: frames) [] env'
+      | EFrame :: env' -> split_aux (curr_frame :: frames) [] env'
       | ev :: env' -> split_aux frames (ev :: curr_frame) env'
     in
     let frames = split_aux [] [] env in
     frames
 
-  let fmt_eval_ctx_to_string_gen (fmt : ctx_formatter) (verbose : bool)
-      (filter : bool) (with_var_types : bool) (ctx : C.eval_ctx) : string =
-    let ended_regions = T.RegionId.Set.to_string None ctx.ended_regions in
+  let eval_ctx_to_string_gen (verbose : bool) (filter : bool)
+      (with_var_types : bool) (ctx : eval_ctx) : string =
+    let fmt_env = eval_ctx_to_fmt_env ctx in
+    let ended_regions = RegionId.Set.to_string None ctx.ended_regions in
     let frames = split_env_according_to_frames ctx.env in
     let num_frames = List.length frames in
     let frames =
@@ -613,194 +481,139 @@ module Contexts = struct
           List.iter
             (fun ev ->
               match ev with
-              | C.Var (DummyBinder _, _) -> num_dummies := !num_abs + 1
-              | C.Var (VarBinder _, _) -> num_bindings := !num_bindings + 1
-              | C.Abs _ -> num_abs := !num_abs + 1
+              | EBinding (BDummy _, _) -> num_dummies := !num_abs + 1
+              | EBinding (BVar _, _) -> num_bindings := !num_bindings + 1
+              | EAbs _ -> num_abs := !num_abs + 1
               | _ -> raise (Failure "Unreachable"))
             f;
           "\n# Frame " ^ string_of_int i ^ ":" ^ "\n- locals: "
           ^ string_of_int !num_bindings
           ^ "\n- dummy bindings: " ^ string_of_int !num_dummies
           ^ "\n- abstractions: " ^ string_of_int !num_abs ^ "\n"
-          ^ env_to_string filter fmt verbose with_var_types f
+          ^ env_to_string filter fmt_env verbose with_var_types f
           ^ "\n")
         frames
     in
     "# Ended regions: " ^ ended_regions ^ "\n" ^ "# " ^ string_of_int num_frames
     ^ " frame(s)\n" ^ String.concat "" frames
 
-  let eval_ctx_to_string_gen (verbose : bool) (filter : bool)
-      (with_var_types : bool) (ctx : C.eval_ctx) : string =
-    let fmt = eval_ctx_to_ctx_formatter ctx in
-    fmt_eval_ctx_to_string_gen fmt verbose filter with_var_types ctx
-
-  let eval_ctx_to_string (ctx : C.eval_ctx) : string =
+  let eval_ctx_to_string (ctx : eval_ctx) : string =
     eval_ctx_to_string_gen false true true ctx
 
-  let eval_ctx_to_string_no_filter (ctx : C.eval_ctx) : string =
+  let eval_ctx_to_string_no_filter (ctx : eval_ctx) : string =
     eval_ctx_to_string_gen false false true ctx
 end
 
-module PC = Contexts (* local module *)
-
 (** Pretty-printing for LLBC ASTs (functions based on an evaluation context) *)
-module EvalCtxLlbcAst = struct
-  let ety_to_string (ctx : C.eval_ctx) (t : T.ety) : string =
-    let fmt = PC.eval_ctx_to_ctx_formatter ctx in
-    let fmt = PC.ctx_to_etype_formatter fmt in
-    PT.ety_to_string fmt t
-
-  let rty_to_string (ctx : C.eval_ctx) (t : T.rty) : string =
-    let fmt = PC.eval_ctx_to_ctx_formatter ctx in
-    let fmt = PC.ctx_to_rtype_formatter fmt in
-    PT.rty_to_string fmt t
-
-  let sty_to_string (ctx : C.eval_ctx) (t : T.sty) : string =
-    let fmt = PC.eval_ctx_to_ctx_formatter ctx in
-    let fmt = PC.ctx_to_stype_formatter fmt in
-    PT.sty_to_string fmt t
-
-  let generic_params_to_strings (ctx : C.eval_ctx) (x : T.generic_params) :
+module EvalCtx = struct
+  open Values
+  open Contexts
+
+  let name_to_string (ctx : eval_ctx) (n : name) : string =
+    let env = eval_ctx_to_fmt_env ctx in
+    name_to_string env n
+
+  let ty_to_string (ctx : eval_ctx) (t : ty) : string =
+    let env = eval_ctx_to_fmt_env ctx in
+    ty_to_string env t
+
+  let generic_params_to_strings (ctx : eval_ctx) (x : generic_params) :
       string list * string list =
-    let fmt = PC.eval_ctx_to_ctx_formatter ctx in
-    let fmt = PC.ctx_to_stype_formatter fmt in
-    PT.generic_params_to_strings fmt x
+    let env = eval_ctx_to_fmt_env ctx in
+    generic_params_to_strings env x
 
-  let egeneric_args_to_string (ctx : C.eval_ctx) (x : T.egeneric_args) : string
-      =
-    let fmt = PC.eval_ctx_to_ctx_formatter ctx in
-    let fmt = PC.ctx_to_etype_formatter fmt in
-    PT.egeneric_args_to_string fmt x
+  let generic_args_to_string (ctx : eval_ctx) (x : generic_args) : string =
+    let env = eval_ctx_to_fmt_env ctx in
+    generic_args_to_string env x
 
-  let rgeneric_args_to_string (ctx : C.eval_ctx) (x : T.rgeneric_args) : string
-      =
-    let fmt = PC.eval_ctx_to_ctx_formatter ctx in
-    let fmt = PC.ctx_to_rtype_formatter fmt in
-    PT.rgeneric_args_to_string fmt x
+  let trait_ref_to_string (ctx : eval_ctx) (x : trait_ref) : string =
+    let env = eval_ctx_to_fmt_env ctx in
+    trait_ref_to_string env x
 
-  let sgeneric_args_to_string (ctx : C.eval_ctx) (x : T.sgeneric_args) : string
-      =
-    let fmt = PC.eval_ctx_to_ctx_formatter ctx in
-    let fmt = PC.ctx_to_stype_formatter fmt in
-    PT.sgeneric_args_to_string fmt x
-
-  let etrait_ref_to_string (ctx : C.eval_ctx) (x : T.etrait_ref) : string =
-    let fmt = PC.eval_ctx_to_ctx_formatter ctx in
-    let fmt = PC.ctx_to_etype_formatter fmt in
-    PT.etrait_ref_to_string fmt x
-
-  let rtrait_ref_to_string (ctx : C.eval_ctx) (x : T.rtrait_ref) : string =
-    let fmt = PC.eval_ctx_to_ctx_formatter ctx in
-    let fmt = PC.ctx_to_rtype_formatter fmt in
-    PT.rtrait_ref_to_string fmt x
-
-  let strait_ref_to_string (ctx : C.eval_ctx) (x : T.strait_ref) : string =
-    let fmt = PC.eval_ctx_to_ctx_formatter ctx in
-    let fmt = PC.ctx_to_stype_formatter fmt in
-    PT.strait_ref_to_string fmt x
-
-  let etrait_instance_id_to_string (ctx : C.eval_ctx) (x : T.etrait_instance_id)
-      : string =
-    let fmt = PC.eval_ctx_to_ctx_formatter ctx in
-    let fmt = PC.ctx_to_etype_formatter fmt in
-    PT.etrait_instance_id_to_string fmt x
-
-  let rtrait_instance_id_to_string (ctx : C.eval_ctx) (x : T.rtrait_instance_id)
-      : string =
-    let fmt = PC.eval_ctx_to_ctx_formatter ctx in
-    let fmt = PC.ctx_to_rtype_formatter fmt in
-    PT.rtrait_instance_id_to_string fmt x
-
-  let strait_instance_id_to_string (ctx : C.eval_ctx) (x : T.strait_instance_id)
-      : string =
-    let fmt = PC.eval_ctx_to_ctx_formatter ctx in
-    let fmt = PC.ctx_to_stype_formatter fmt in
-    PT.strait_instance_id_to_string fmt x
-
-  let borrow_content_to_string (ctx : C.eval_ctx) (bc : V.borrow_content) :
+  let trait_instance_id_to_string (ctx : eval_ctx) (x : trait_instance_id) :
       string =
-    let fmt = PC.eval_ctx_to_ctx_formatter ctx in
-    PV.borrow_content_to_string fmt bc
+    let env = eval_ctx_to_fmt_env ctx in
+    trait_instance_id_to_string env x
 
-  let loan_content_to_string (ctx : C.eval_ctx) (lc : V.loan_content) : string =
-    let fmt = PC.eval_ctx_to_ctx_formatter ctx in
-    PV.loan_content_to_string fmt lc
+  let borrow_content_to_string (ctx : eval_ctx) (bc : borrow_content) : string =
+    let env = eval_ctx_to_fmt_env ctx in
+    borrow_content_to_string env bc
 
-  let aborrow_content_to_string (ctx : C.eval_ctx) (bc : V.aborrow_content) :
-      string =
-    let fmt = PC.eval_ctx_to_ctx_formatter ctx in
-    PV.aborrow_content_to_string fmt bc
+  let loan_content_to_string (ctx : eval_ctx) (lc : loan_content) : string =
+    let env = eval_ctx_to_fmt_env ctx in
+    loan_content_to_string env lc
 
-  let aloan_content_to_string (ctx : C.eval_ctx) (lc : V.aloan_content) : string
+  let aborrow_content_to_string (ctx : eval_ctx) (bc : aborrow_content) : string
       =
-    let fmt = PC.eval_ctx_to_ctx_formatter ctx in
-    PV.aloan_content_to_string fmt lc
+    let env = eval_ctx_to_fmt_env ctx in
+    aborrow_content_to_string env bc
 
-  let aproj_to_string (ctx : C.eval_ctx) (p : V.aproj) : string =
-    let fmt = PC.eval_ctx_to_ctx_formatter ctx in
-    PV.aproj_to_string fmt p
+  let aloan_content_to_string (ctx : eval_ctx) (lc : aloan_content) : string =
+    let env = eval_ctx_to_fmt_env ctx in
+    aloan_content_to_string env lc
 
-  let symbolic_value_to_string (ctx : C.eval_ctx) (sv : V.symbolic_value) :
-      string =
-    let fmt = PC.eval_ctx_to_ctx_formatter ctx in
-    let fmt = PC.ctx_to_rtype_formatter fmt in
-    PV.symbolic_value_to_string fmt sv
+  let aproj_to_string (ctx : eval_ctx) (p : aproj) : string =
+    let env = eval_ctx_to_fmt_env ctx in
+    aproj_to_string env p
+
+  let symbolic_value_to_string (ctx : eval_ctx) (sv : symbolic_value) : string =
+    let env = eval_ctx_to_fmt_env ctx in
+    symbolic_value_to_string env sv
 
-  let typed_value_to_string (ctx : C.eval_ctx) (v : V.typed_value) : string =
-    let fmt = PC.eval_ctx_to_ctx_formatter ctx in
-    PV.typed_value_to_string fmt v
+  let typed_value_to_string (ctx : eval_ctx) (v : typed_value) : string =
+    let env = eval_ctx_to_fmt_env ctx in
+    typed_value_to_string env v
 
-  let typed_avalue_to_string (ctx : C.eval_ctx) (v : V.typed_avalue) : string =
-    let fmt = PC.eval_ctx_to_ctx_formatter ctx in
-    PV.typed_avalue_to_string fmt v
+  let typed_avalue_to_string (ctx : eval_ctx) (v : typed_avalue) : string =
+    let env = eval_ctx_to_fmt_env ctx in
+    typed_avalue_to_string env v
 
-  let place_to_string (ctx : C.eval_ctx) (op : E.place) : string =
-    let fmt = PC.eval_ctx_to_ast_formatter ctx in
-    PE.place_to_string fmt op
+  let place_to_string (ctx : eval_ctx) (op : place) : string =
+    let env = eval_ctx_to_fmt_env ctx in
+    place_to_string env op
 
-  let operand_to_string (ctx : C.eval_ctx) (op : E.operand) : string =
-    let fmt = PC.eval_ctx_to_ast_formatter ctx in
-    PE.operand_to_string fmt op
+  let operand_to_string (ctx : eval_ctx) (op : operand) : string =
+    let env = eval_ctx_to_fmt_env ctx in
+    operand_to_string env op
 
-  let call_to_string (ctx : C.eval_ctx) (call : A.call) : string =
-    let fmt = PC.eval_ctx_to_ast_formatter ctx in
-    PA.call_to_string fmt "" call
+  let call_to_string (ctx : eval_ctx) (call : call) : string =
+    let env = eval_ctx_to_fmt_env ctx in
+    call_to_string env "" call
 
-  let fun_decl_to_string (ctx : C.eval_ctx) (f : A.fun_decl) : string =
-    let fmt = PC.eval_ctx_to_ast_formatter ctx in
-    PA.fun_decl_to_string fmt "" "  " f
+  let fun_decl_to_string (ctx : eval_ctx) (f : fun_decl) : string =
+    let env = eval_ctx_to_fmt_env ctx in
+    fun_decl_to_string env "" "  " f
 
-  let fun_sig_to_string (ctx : C.eval_ctx) (x : A.fun_sig) : string =
-    let fmt = PC.eval_ctx_to_ast_formatter ctx in
-    PA.fun_sig_to_string fmt "" "  " x
+  let fun_sig_to_string (ctx : eval_ctx) (x : fun_sig) : string =
+    let env = eval_ctx_to_fmt_env ctx in
+    fun_sig_to_string env "" "  " x
 
-  let inst_fun_sig_to_string (ctx : C.eval_ctx) (x : LlbcAst.inst_fun_sig) :
+  let inst_fun_sig_to_string (ctx : eval_ctx) (x : LlbcAst.inst_fun_sig) :
       string =
-    let fmt = PC.eval_ctx_to_ast_formatter ctx in
-    let fmt = PC.ast_to_value_formatter fmt in
-    PV.inst_fun_sig_to_string fmt x
-
-  let fun_id_or_trait_method_ref_to_string (ctx : C.eval_ctx)
-      (x : E.fun_id_or_trait_method_ref) : string =
-    let fmt = PC.eval_ctx_to_ast_formatter ctx in
-    PE.fun_id_or_trait_method_ref_to_string fmt x "..."
-
-  let statement_to_string (ctx : C.eval_ctx) (indent : string)
-      (indent_incr : string) (e : A.statement) : string =
-    let fmt = PC.eval_ctx_to_ast_formatter ctx in
-    PA.statement_to_string fmt indent indent_incr e
-
-  let trait_impl_to_string (ctx : C.eval_ctx) (timpl : A.trait_impl) : string =
-    let fmt = PC.eval_ctx_to_ast_formatter ctx in
-    PA.trait_impl_to_string fmt "  " "  " timpl
-
-  let env_elem_to_string (ctx : C.eval_ctx) (indent : string)
-      (indent_incr : string) (ev : C.env_elem) : string =
-    let fmt = PC.eval_ctx_to_ctx_formatter ctx in
-    PC.env_elem_to_string fmt false true indent indent_incr ev
-
-  let abs_to_string (ctx : C.eval_ctx) (indent : string) (indent_incr : string)
-      (abs : V.abs) : string =
-    let fmt = PC.eval_ctx_to_ctx_formatter ctx in
-    PV.abs_to_string fmt false indent indent_incr abs
+    let env = eval_ctx_to_fmt_env ctx in
+    inst_fun_sig_to_string env x
+
+  let fun_id_or_trait_method_ref_to_string (ctx : eval_ctx)
+      (x : fun_id_or_trait_method_ref) : string =
+    let env = eval_ctx_to_fmt_env ctx in
+    fun_id_or_trait_method_ref_to_string env x "..."
+
+  let statement_to_string (ctx : eval_ctx) (indent : string)
+      (indent_incr : string) (e : statement) : string =
+    let env = eval_ctx_to_fmt_env ctx in
+    statement_to_string env indent indent_incr e
+
+  let trait_impl_to_string (ctx : eval_ctx) (timpl : trait_impl) : string =
+    let env = eval_ctx_to_fmt_env ctx in
+    trait_impl_to_string env "  " "  " timpl
+
+  let env_elem_to_string (ctx : eval_ctx) (indent : string)
+      (indent_incr : string) (ev : env_elem) : string =
+    let env = eval_ctx_to_fmt_env ctx in
+    env_elem_to_string env false true indent indent_incr ev
+
+  let abs_to_string (ctx : eval_ctx) (indent : string) (indent_incr : string)
+      (abs : abs) : string =
+    let env = eval_ctx_to_fmt_env ctx in
+    abs_to_string env false indent indent_incr abs
 end
diff --git a/compiler/PrintPure.ml b/compiler/PrintPure.ml
index ec75fcfd..5d8297d3 100644
--- a/compiler/PrintPure.ml
+++ b/compiler/PrintPure.ml
@@ -3,335 +3,251 @@
 open Pure
 open PureUtils
 
-type type_formatter = {
-  type_var_id_to_string : TypeVarId.id -> string;
-  type_decl_id_to_string : TypeDeclId.id -> string;
-  const_generic_var_id_to_string : ConstGenericVarId.id -> string;
-  global_decl_id_to_string : GlobalDeclId.id -> string;
-  trait_decl_id_to_string : TraitDeclId.id -> string;
-  trait_impl_id_to_string : TraitImplId.id -> string;
-  trait_clause_id_to_string : TraitClauseId.id -> string;
+(** The formatting context for pure definitions uses non-pure definitions
+    to lookup names. The main reason is that when building the pure definitions
+    like in [SymbolicToPure] we don't have a pure context available, while
+    at every stage we have the original LLBC definitions at hand.
+ *)
+type fmt_env = {
+  type_decls : Types.type_decl TypeDeclId.Map.t;
+  fun_decls : LlbcAst.fun_decl FunDeclId.Map.t;
+  global_decls : LlbcAst.global_decl GlobalDeclId.Map.t;
+  trait_decls : LlbcAst.trait_decl TraitDeclId.Map.t;
+  trait_impls : LlbcAst.trait_impl TraitImplId.Map.t;
+  generics : generic_params;
+  locals : (VarId.id * string option) list;
 }
 
-type value_formatter = {
-  type_var_id_to_string : TypeVarId.id -> string;
-  type_decl_id_to_string : TypeDeclId.id -> string;
-  const_generic_var_id_to_string : ConstGenericVarId.id -> string;
-  global_decl_id_to_string : GlobalDeclId.id -> string;
-  adt_variant_to_string : TypeDeclId.id -> VariantId.id -> string;
-  var_id_to_string : VarId.id -> string;
-  adt_field_names : TypeDeclId.id -> VariantId.id option -> string list option;
-  trait_decl_id_to_string : TraitDeclId.id -> string;
-  trait_impl_id_to_string : TraitImplId.id -> string;
-  trait_clause_id_to_string : TraitClauseId.id -> string;
-}
+let var_id_to_pretty_string (id : var_id) : string = "v@" ^ VarId.to_string id
+
+let type_var_id_to_string (env : fmt_env) (id : type_var_id) : string =
+  (* Note that the types are not necessarily ordered following their indices *)
+  match
+    List.find_opt (fun (x : type_var) -> x.index = id) env.generics.types
+  with
+  | None -> Print.Types.type_var_id_to_pretty_string id
+  | Some x -> Print.Types.type_var_to_string x
 
-let value_to_type_formatter (fmt : value_formatter) : type_formatter =
+let const_generic_var_id_to_string (env : fmt_env) (id : const_generic_var_id) :
+    string =
+  (* Note that the regions are not necessarily ordered following their indices *)
+  match
+    List.find_opt
+      (fun (x : const_generic_var) -> x.index = id)
+      env.generics.const_generics
+  with
+  | None -> Print.Types.const_generic_var_id_to_pretty_string id
+  | Some x -> Print.Types.const_generic_var_to_string x
+
+let var_id_to_string (env : fmt_env) (id : VarId.id) : string =
+  match List.find_opt (fun (i, _) -> i = id) env.locals with
+  | None -> var_id_to_pretty_string id
+  | Some (_, name) -> (
+      match name with
+      | None -> var_id_to_pretty_string id
+      | Some name -> name ^ "^" ^ VarId.to_string id)
+
+let trait_clause_id_to_string = Print.Types.trait_clause_id_to_string
+
+let fmt_env_to_llbc_fmt_env (env : fmt_env) : Print.fmt_env =
   {
-    type_var_id_to_string = fmt.type_var_id_to_string;
-    type_decl_id_to_string = fmt.type_decl_id_to_string;
-    const_generic_var_id_to_string = fmt.const_generic_var_id_to_string;
-    global_decl_id_to_string = fmt.global_decl_id_to_string;
-    trait_decl_id_to_string = fmt.trait_decl_id_to_string;
-    trait_impl_id_to_string = fmt.trait_impl_id_to_string;
-    trait_clause_id_to_string = fmt.trait_clause_id_to_string;
+    type_decls = env.type_decls;
+    fun_decls = env.fun_decls;
+    global_decls = env.global_decls;
+    trait_decls = env.trait_decls;
+    trait_impls = env.trait_impls;
+    generics = TypesUtils.empty_generic_params;
+    preds = TypesUtils.empty_predicates;
+    locals = [];
   }
 
-(* TODO: we need to store which variables we have encountered so far, and
-   remove [var_id_to_string].
-*)
-type ast_formatter = {
-  type_var_id_to_string : TypeVarId.id -> string;
-  type_decl_id_to_string : TypeDeclId.id -> string;
-  const_generic_var_id_to_string : ConstGenericVarId.id -> string;
-  adt_variant_to_string : TypeDeclId.id -> VariantId.id -> string;
-  var_id_to_string : VarId.id -> string;
-  adt_field_to_string :
-    TypeDeclId.id -> VariantId.id option -> FieldId.id -> string option;
-  adt_field_names : TypeDeclId.id -> VariantId.id option -> string list option;
-  fun_decl_id_to_string : FunDeclId.id -> string;
-  global_decl_id_to_string : GlobalDeclId.id -> string;
-  trait_decl_id_to_string : TraitDeclId.id -> string;
-  trait_impl_id_to_string : TraitImplId.id -> string;
-  trait_clause_id_to_string : TraitClauseId.id -> string;
-}
-
-let ast_to_value_formatter (fmt : ast_formatter) : value_formatter =
+let decls_ctx_to_fmt_env (ctx : Contexts.decls_ctx) : fmt_env =
   {
-    type_var_id_to_string = fmt.type_var_id_to_string;
-    type_decl_id_to_string = fmt.type_decl_id_to_string;
-    const_generic_var_id_to_string = fmt.const_generic_var_id_to_string;
-    global_decl_id_to_string = fmt.global_decl_id_to_string;
-    adt_variant_to_string = fmt.adt_variant_to_string;
-    var_id_to_string = fmt.var_id_to_string;
-    adt_field_names = fmt.adt_field_names;
-    trait_decl_id_to_string = fmt.trait_decl_id_to_string;
-    trait_impl_id_to_string = fmt.trait_impl_id_to_string;
-    trait_clause_id_to_string = fmt.trait_clause_id_to_string;
+    type_decls = ctx.type_ctx.type_decls;
+    fun_decls = ctx.fun_ctx.fun_decls;
+    global_decls = ctx.global_ctx.global_decls;
+    trait_decls = ctx.trait_decls_ctx.trait_decls;
+    trait_impls = ctx.trait_impls_ctx.trait_impls;
+    generics = empty_generic_params;
+    locals = [];
   }
 
-let ast_to_type_formatter (fmt : ast_formatter) : type_formatter =
-  let fmt = ast_to_value_formatter fmt in
-  value_to_type_formatter fmt
+let name_to_string (env : fmt_env) =
+  Print.Types.name_to_string (fmt_env_to_llbc_fmt_env env)
+
+let type_decl_id_to_string (env : fmt_env) =
+  Print.Types.type_decl_id_to_string (fmt_env_to_llbc_fmt_env env)
+
+let global_decl_id_to_string (env : fmt_env) =
+  Print.Types.global_decl_id_to_string (fmt_env_to_llbc_fmt_env env)
+
+let fun_decl_id_to_string (env : fmt_env) =
+  Print.Expressions.fun_decl_id_to_string (fmt_env_to_llbc_fmt_env env)
+
+let trait_decl_id_to_string (env : fmt_env) =
+  Print.Types.trait_decl_id_to_string (fmt_env_to_llbc_fmt_env env)
+
+let trait_impl_id_to_string (env : fmt_env) =
+  Print.Types.trait_impl_id_to_string (fmt_env_to_llbc_fmt_env env)
+
+let adt_field_to_string (env : fmt_env) =
+  Print.Types.adt_field_to_string (fmt_env_to_llbc_fmt_env env)
+
+let adt_variant_from_type_decl_id_to_string (env : fmt_env) =
+  Print.Types.adt_variant_to_string (fmt_env_to_llbc_fmt_env env)
+
+let adt_field_names (env : fmt_env) =
+  Print.Types.adt_field_names (fmt_env_to_llbc_fmt_env env)
 
-let name_to_string = Print.name_to_string
-let fun_name_to_string = Print.fun_name_to_string
-let global_name_to_string = Print.global_name_to_string
 let option_to_string = Print.option_to_string
 let type_var_to_string = Print.Types.type_var_to_string
 let const_generic_var_to_string = Print.Types.const_generic_var_to_string
-let integer_type_to_string = Print.PrimitiveValues.integer_type_to_string
-let literal_type_to_string = Print.PrimitiveValues.literal_type_to_string
-let scalar_value_to_string = Print.PrimitiveValues.scalar_value_to_string
-let literal_to_string = Print.PrimitiveValues.literal_to_string
-
-(* Remark: not using generic_params on purpose, because we may use parameters
-   which either come from LLBC or from pure, and the [generic_params] type
-   for those ASTs is not the same. Note that it works because we actually don't
-   need to know the trait clauses to print the AST: we can thus ignore them.
-*)
-let mk_type_formatter (type_decls : T.type_decl TypeDeclId.Map.t)
-    (global_decls : A.global_decl GlobalDeclId.Map.t)
-    (trait_decls : A.trait_decl TraitDeclId.Map.t)
-    (trait_impls : A.trait_impl TraitImplId.Map.t) (type_params : type_var list)
-    (const_generic_params : const_generic_var list) : type_formatter =
-  let type_var_id_to_string vid =
-    let var = TypeVarId.nth type_params vid in
-    type_var_to_string var
-  in
-  let const_generic_var_id_to_string vid =
-    let var = ConstGenericVarId.nth const_generic_params vid in
-    const_generic_var_to_string var
-  in
-  let type_decl_id_to_string def_id =
-    let def = TypeDeclId.Map.find def_id type_decls in
-    name_to_string def.name
-  in
-  let global_decl_id_to_string def_id =
-    let def = GlobalDeclId.Map.find def_id global_decls in
-    name_to_string def.name
-  in
-  let trait_decl_id_to_string def_id =
-    let def = TraitDeclId.Map.find def_id trait_decls in
-    name_to_string def.name
-  in
-  let trait_impl_id_to_string def_id =
-    let def = TraitImplId.Map.find def_id trait_impls in
-    name_to_string def.name
-  in
-  let trait_clause_id_to_string id =
-    Print.PT.trait_clause_id_to_pretty_string id
-  in
-  {
-    type_var_id_to_string;
-    type_decl_id_to_string;
-    const_generic_var_id_to_string;
-    global_decl_id_to_string;
-    trait_decl_id_to_string;
-    trait_impl_id_to_string;
-    trait_clause_id_to_string;
-  }
-
-(* TODO: there is a bit of duplication with Print.fun_decl_to_ast_formatter.
-
-   TODO: use the pure defs as inputs? Note that it is a bit annoying for the
-   functions (there is a difference between the forward/backward functions...)
-   while we only need those definitions to lookup proper names for the def ids.
-*)
-let mk_ast_formatter (type_decls : T.type_decl TypeDeclId.Map.t)
-    (fun_decls : A.fun_decl FunDeclId.Map.t)
-    (global_decls : A.global_decl GlobalDeclId.Map.t)
-    (trait_decls : A.trait_decl TraitDeclId.Map.t)
-    (trait_impls : A.trait_impl TraitImplId.Map.t) (type_params : type_var list)
-    (const_generic_params : const_generic_var list) : ast_formatter =
-  let ({
-         type_var_id_to_string;
-         type_decl_id_to_string;
-         const_generic_var_id_to_string;
-         global_decl_id_to_string;
-         trait_decl_id_to_string;
-         trait_impl_id_to_string;
-         trait_clause_id_to_string;
-       }
-        : type_formatter) =
-    mk_type_formatter type_decls global_decls trait_decls trait_impls
-      type_params const_generic_params
-  in
-  let adt_variant_to_string =
-    Print.Types.type_ctx_to_adt_variant_to_string_fun type_decls
-  in
-  let var_id_to_string vid =
-    (* TODO: somehow lookup in the context *)
-    "^" ^ VarId.to_string vid
-  in
-  let adt_field_names =
-    Print.Types.type_ctx_to_adt_field_names_fun type_decls
-  in
-  let adt_field_to_string =
-    Print.Types.type_ctx_to_adt_field_to_string_fun type_decls
-  in
-  let fun_decl_id_to_string def_id =
-    let def = FunDeclId.Map.find def_id fun_decls in
-    fun_name_to_string def.name
-  in
-  {
-    type_var_id_to_string;
-    const_generic_var_id_to_string;
-    type_decl_id_to_string;
-    adt_variant_to_string;
-    var_id_to_string;
-    adt_field_names;
-    adt_field_to_string;
-    fun_decl_id_to_string;
-    global_decl_id_to_string;
-    trait_decl_id_to_string;
-    trait_impl_id_to_string;
-    trait_clause_id_to_string;
-  }
+let integer_type_to_string = Print.Values.integer_type_to_string
+let literal_type_to_string = Print.Values.literal_type_to_string
+let scalar_value_to_string = Print.Values.scalar_value_to_string
+let literal_to_string = Print.Values.literal_to_string
 
 let assumed_ty_to_string (aty : assumed_ty) : string =
   match aty with
-  | State -> "State"
-  | Result -> "Result"
-  | Error -> "Error"
-  | Fuel -> "Fuel"
-  | Array -> "Array"
-  | Slice -> "Slice"
-  | Str -> "Str"
-  | RawPtr Mut -> "MutRawPtr"
-  | RawPtr Const -> "ConstRawPtr"
-
-let type_id_to_string (fmt : type_formatter) (id : type_id) : string =
+  | TState -> "State"
+  | TResult -> "Result"
+  | TError -> "Error"
+  | TFuel -> "Fuel"
+  | TArray -> "Array"
+  | TSlice -> "Slice"
+  | TStr -> "Str"
+  | TRawPtr Mut -> "MutRawPtr"
+  | TRawPtr Const -> "ConstRawPtr"
+
+let type_id_to_string (env : fmt_env) (id : type_id) : string =
   match id with
-  | AdtId id -> fmt.type_decl_id_to_string id
-  | Tuple -> ""
-  | Assumed aty -> assumed_ty_to_string aty
+  | TAdtId id -> type_decl_id_to_string env id
+  | TTuple -> ""
+  | TAssumed aty -> assumed_ty_to_string aty
 
 (* TODO: duplicates  Charon.PrintTypes.const_generic_to_string *)
-let const_generic_to_string (fmt : type_formatter) (cg : T.const_generic) :
-    string =
+let const_generic_to_string (env : fmt_env) (cg : const_generic) : string =
   match cg with
-  | ConstGenericGlobal id -> fmt.global_decl_id_to_string id
-  | ConstGenericVar id -> fmt.const_generic_var_id_to_string id
-  | ConstGenericValue lit -> literal_to_string lit
+  | CgGlobal id -> global_decl_id_to_string env id
+  | CgVar id -> const_generic_var_id_to_string env id
+  | CgValue lit -> literal_to_string lit
 
-let rec ty_to_string (fmt : type_formatter) (inside : bool) (ty : ty) : string =
+let rec ty_to_string (env : fmt_env) (inside : bool) (ty : ty) : string =
   match ty with
-  | Adt (id, generics) -> (
+  | TAdt (id, generics) -> (
       match id with
-      | Tuple ->
-          let generics = generic_args_to_strings fmt false generics in
+      | TTuple ->
+          let generics = generic_args_to_strings env false generics in
           "(" ^ String.concat " * " generics ^ ")"
-      | AdtId _ | Assumed _ ->
-          let generics = generic_args_to_strings fmt true generics in
+      | TAdtId _ | TAssumed _ ->
+          let generics = generic_args_to_strings env true generics in
           let generics_s =
             if generics = [] then "" else " " ^ String.concat " " generics
           in
-          let ty_s = type_id_to_string fmt id ^ generics_s in
+          let ty_s = type_id_to_string env id ^ generics_s in
           if generics <> [] && inside then "(" ^ ty_s ^ ")" else ty_s)
-  | TypeVar tv -> fmt.type_var_id_to_string tv
-  | Literal lty -> literal_type_to_string lty
-  | Arrow (arg_ty, ret_ty) ->
+  | TVar tv -> type_var_id_to_string env tv
+  | TLiteral lty -> literal_type_to_string lty
+  | TArrow (arg_ty, ret_ty) ->
       let ty =
-        ty_to_string fmt true arg_ty ^ " -> " ^ ty_to_string fmt false ret_ty
+        ty_to_string env true arg_ty ^ " -> " ^ ty_to_string env false ret_ty
       in
       if inside then "(" ^ ty ^ ")" else ty
-  | TraitType (trait_ref, generics, type_name) ->
-      let trait_ref = trait_ref_to_string fmt false trait_ref in
+  | TTraitType (trait_ref, generics, type_name) ->
+      let trait_ref = trait_ref_to_string env false trait_ref in
       let s =
         if generics = empty_generic_args then trait_ref ^ "::" ^ type_name
         else
-          let generics = generic_args_to_string fmt generics in
+          let generics = generic_args_to_string env generics in
           "(" ^ trait_ref ^ " " ^ generics ^ ")::" ^ type_name
       in
       if inside then "(" ^ s ^ ")" else s
 
-and generic_args_to_strings (fmt : type_formatter) (inside : bool)
+and generic_args_to_strings (env : fmt_env) (inside : bool)
     (generics : generic_args) : string list =
-  let tys = List.map (ty_to_string fmt inside) generics.types in
-  let cgs = List.map (const_generic_to_string fmt) generics.const_generics in
+  let tys = List.map (ty_to_string env inside) generics.types in
+  let cgs = List.map (const_generic_to_string env) generics.const_generics in
   let trait_refs =
-    List.map (trait_ref_to_string fmt inside) generics.trait_refs
+    List.map (trait_ref_to_string env inside) generics.trait_refs
   in
   List.concat [ tys; cgs; trait_refs ]
 
-and generic_args_to_string (fmt : type_formatter) (generics : generic_args) :
-    string =
-  String.concat " " (generic_args_to_strings fmt true generics)
+and generic_args_to_string (env : fmt_env) (generics : generic_args) : string =
+  String.concat " " (generic_args_to_strings env true generics)
 
-and trait_ref_to_string (fmt : type_formatter) (inside : bool) (tr : trait_ref)
-    : string =
-  let trait_id = trait_instance_id_to_string fmt false tr.trait_id in
-  let generics = generic_args_to_string fmt tr.generics in
+and trait_ref_to_string (env : fmt_env) (inside : bool) (tr : trait_ref) :
+    string =
+  let trait_id = trait_instance_id_to_string env false tr.trait_id in
+  let generics = generic_args_to_string env tr.generics in
   let s = trait_id ^ generics in
   if tr.generics = empty_generic_args || not inside then s else "(" ^ s ^ ")"
 
-and trait_instance_id_to_string (fmt : type_formatter) (inside : bool)
+and trait_instance_id_to_string (env : fmt_env) (inside : bool)
     (id : trait_instance_id) : string =
   match id with
   | Self -> "Self"
-  | TraitImpl id -> fmt.trait_impl_id_to_string id
-  | Clause id -> fmt.trait_clause_id_to_string id
+  | TraitImpl id -> trait_impl_id_to_string env id
+  | Clause id -> trait_clause_id_to_string env id
   | ParentClause (inst_id, _decl_id, clause_id) ->
-      let inst_id = trait_instance_id_to_string fmt false inst_id in
-      let clause_id = fmt.trait_clause_id_to_string clause_id in
+      let inst_id = trait_instance_id_to_string env false inst_id in
+      let clause_id = trait_clause_id_to_string env clause_id in
       "parent(" ^ inst_id ^ ")::" ^ clause_id
   | ItemClause (inst_id, _decl_id, item_name, clause_id) ->
-      let inst_id = trait_instance_id_to_string fmt false inst_id in
-      let clause_id = fmt.trait_clause_id_to_string clause_id in
+      let inst_id = trait_instance_id_to_string env false inst_id in
+      let clause_id = trait_clause_id_to_string env clause_id in
       "(" ^ inst_id ^ ")::" ^ item_name ^ "::[" ^ clause_id ^ "]"
-  | TraitRef tr -> trait_ref_to_string fmt inside tr
+  | TraitRef tr -> trait_ref_to_string env inside tr
   | UnknownTrait msg -> "UNKNOWN(" ^ msg ^ ")"
 
-let trait_clause_to_string (fmt : type_formatter) (clause : trait_clause) :
-    string =
-  let clause_id = fmt.trait_clause_id_to_string clause.clause_id in
-  let trait_id = fmt.trait_decl_id_to_string clause.trait_id in
-  let generics = generic_args_to_strings fmt true clause.generics in
+let trait_clause_to_string (env : fmt_env) (clause : trait_clause) : string =
+  let clause_id = trait_clause_id_to_string env clause.clause_id in
+  let trait_id = trait_decl_id_to_string env clause.trait_id in
+  let generics = generic_args_to_strings env true clause.generics in
   let generics =
     if generics = [] then "" else " " ^ String.concat " " generics
   in
   "[" ^ clause_id ^ "]: " ^ trait_id ^ generics
 
-let generic_params_to_strings (fmt : type_formatter) (generics : generic_params)
-    : string list =
+let generic_params_to_strings (env : fmt_env) (generics : generic_params) :
+    string list =
   let tys = List.map type_var_to_string generics.types in
   let cgs = List.map const_generic_var_to_string generics.const_generics in
   let trait_clauses =
-    List.map (trait_clause_to_string fmt) generics.trait_clauses
+    List.map (trait_clause_to_string env) generics.trait_clauses
   in
   List.concat [ tys; cgs; trait_clauses ]
 
-let field_to_string fmt inside (f : field) : string =
+let field_to_string env inside (f : field) : string =
   match f.field_name with
-  | None -> ty_to_string fmt inside f.field_ty
+  | None -> ty_to_string env inside f.field_ty
   | Some field_name ->
-      let s = field_name ^ " : " ^ ty_to_string fmt false f.field_ty in
+      let s = field_name ^ " : " ^ ty_to_string env false f.field_ty in
       if inside then "(" ^ s ^ ")" else s
 
-let variant_to_string fmt (v : variant) : string =
+let variant_to_string env (v : variant) : string =
   v.variant_name ^ "("
-  ^ String.concat ", " (List.map (field_to_string fmt false) v.fields)
+  ^ String.concat ", " (List.map (field_to_string env false) v.fields)
   ^ ")"
 
-let type_decl_to_string (fmt : type_formatter) (def : type_decl) : string =
-  let name = name_to_string def.name in
+let type_decl_to_string (env : fmt_env) (def : type_decl) : string =
+  let env = { env with generics = def.generics } in
+  let name = def.name in
   let params =
     if def.generics = empty_generic_params then ""
-    else " " ^ String.concat " " (generic_params_to_strings fmt def.generics)
+    else " " ^ String.concat " " (generic_params_to_strings env def.generics)
   in
   match def.kind with
   | Struct fields ->
       if List.length fields > 0 then
         let fields =
           String.concat ","
-            (List.map (fun f -> "\n  " ^ field_to_string fmt false f) fields)
+            (List.map (fun f -> "\n  " ^ field_to_string env false f) fields)
         in
         "struct " ^ name ^ params ^ "{" ^ fields ^ "}"
       else "struct " ^ name ^ params ^ "{}"
   | Enum variants ->
       let variants =
-        List.map (fun v -> "|  " ^ variant_to_string fmt v) variants
+        List.map (fun v -> "|  " ^ variant_to_string env v) variants
       in
       let variants = String.concat "\n" variants in
       "enum " ^ name ^ params ^ " =\n" ^ variants
@@ -342,113 +258,115 @@ let var_to_varname (v : var) : string =
   | Some name -> name ^ "^" ^ VarId.to_string v.id
   | None -> "^" ^ VarId.to_string v.id
 
-let var_to_string (fmt : type_formatter) (v : var) : string =
+let var_to_string (env : fmt_env) (v : var) : string =
   let varname = var_to_varname v in
-  "(" ^ varname ^ " : " ^ ty_to_string fmt false v.ty ^ ")"
+  "(" ^ varname ^ " : " ^ ty_to_string env false v.ty ^ ")"
 
-let rec mprojection_to_string (fmt : ast_formatter) (inside : string)
+let rec mprojection_to_string (env : fmt_env) (inside : string)
     (p : mprojection) : string =
   match p with
   | [] -> inside
   | pe :: p' -> (
-      let s = mprojection_to_string fmt inside p' in
+      let s = mprojection_to_string env inside p' in
       match pe.pkind with
       | E.ProjTuple _ -> "(" ^ s ^ ")." ^ T.FieldId.to_string pe.field_id
       | E.ProjAdt (adt_id, opt_variant_id) -> (
           let field_name =
-            match fmt.adt_field_to_string adt_id opt_variant_id pe.field_id with
+            match adt_field_to_string env adt_id opt_variant_id pe.field_id with
             | Some field_name -> field_name
             | None -> T.FieldId.to_string pe.field_id
           in
           match opt_variant_id with
           | None -> "(" ^ s ^ ")." ^ field_name
           | Some variant_id ->
-              let variant_name = fmt.adt_variant_to_string adt_id variant_id in
+              let variant_name =
+                adt_variant_from_type_decl_id_to_string env adt_id variant_id
+              in
               "(" ^ s ^ " as " ^ variant_name ^ ")." ^ field_name))
 
-let mplace_to_string (fmt : ast_formatter) (p : mplace) : string =
+let mplace_to_string (env : fmt_env) (p : mplace) : string =
   let name = match p.name with None -> "" | Some name -> name in
   (* We add the "llbc" suffix to the variable index, because meta-places
    * use indices of the variables in the original LLBC program, while
    * regular places use indices for the pure variables: we want to make
    * this explicit, otherwise it is confusing. *)
   let name = name ^ "^" ^ E.VarId.to_string p.var_id ^ "llbc" in
-  mprojection_to_string fmt name p.projection
+  mprojection_to_string env name p.projection
 
-let adt_variant_to_string (fmt : value_formatter) (adt_id : type_id)
+let adt_variant_to_string (env : fmt_env) (adt_id : type_id)
     (variant_id : VariantId.id option) : string =
   match adt_id with
-  | Tuple -> "Tuple"
-  | AdtId def_id -> (
+  | TTuple -> "Tuple"
+  | TAdtId def_id -> (
       (* "Regular" ADT *)
       match variant_id with
-      | Some vid -> fmt.adt_variant_to_string def_id vid
-      | None -> fmt.type_decl_id_to_string def_id)
-  | Assumed aty -> (
+      | Some vid -> adt_variant_from_type_decl_id_to_string env def_id vid
+      | None -> type_decl_id_to_string env def_id)
+  | TAssumed aty -> (
       (* Assumed type *)
       match aty with
-      | State | Array | Slice | Str | RawPtr _ ->
+      | TState | TArray | TSlice | TStr | TRawPtr _ ->
           (* Those types are opaque: we can't get there *)
           raise (Failure "Unreachable")
-      | Result ->
+      | TResult ->
           let variant_id = Option.get variant_id in
           if variant_id = result_return_id then "@Result::Return"
           else if variant_id = result_fail_id then "@Result::Fail"
           else
             raise (Failure "Unreachable: improper variant id for result type")
-      | Error ->
+      | TError ->
           let variant_id = Option.get variant_id in
           if variant_id = error_failure_id then "@Error::Failure"
           else if variant_id = error_out_of_fuel_id then "@Error::OutOfFuel"
           else raise (Failure "Unreachable: improper variant id for error type")
-      | Fuel ->
+      | TFuel ->
           let variant_id = Option.get variant_id in
           if variant_id = fuel_zero_id then "@Fuel::Zero"
           else if variant_id = fuel_succ_id then "@Fuel::Succ"
           else raise (Failure "Unreachable: improper variant id for fuel type"))
 
-let adt_field_to_string (fmt : value_formatter) (adt_id : type_id)
+let adt_field_to_string (env : fmt_env) (adt_id : type_id)
     (field_id : FieldId.id) : string =
   match adt_id with
-  | Tuple ->
+  | TTuple ->
       raise (Failure "Unreachable")
       (* Tuples don't use the opaque field id for the field indices, but [int] *)
-  | AdtId def_id -> (
+  | TAdtId def_id -> (
       (* "Regular" ADT *)
-      let fields = fmt.adt_field_names def_id None in
+      let fields = adt_field_names env def_id None in
       match fields with
       | None -> FieldId.to_string field_id
       | Some fields -> FieldId.nth fields field_id)
-  | Assumed aty -> (
+  | TAssumed aty -> (
       (* Assumed type *)
       match aty with
-      | State | Fuel | Array | Slice | Str ->
+      | TState | TFuel | TArray | TSlice | TStr ->
           (* Opaque types: we can't get there *)
           raise (Failure "Unreachable")
-      | Result | Error | RawPtr _ ->
+      | TResult | TError | TRawPtr _ ->
           (* Enumerations: we can't get there *)
           raise (Failure "Unreachable"))
 
 (** TODO: we don't need a general function anymore (it is now only used for
     patterns)
  *)
-let adt_g_value_to_string (fmt : value_formatter)
-    (value_to_string : 'v -> string) (variant_id : VariantId.id option)
-    (field_values : 'v list) (ty : ty) : string =
+let adt_g_value_to_string (env : fmt_env) (value_to_string : 'v -> string)
+    (variant_id : VariantId.id option) (field_values : 'v list) (ty : ty) :
+    string =
   let field_values = List.map value_to_string field_values in
   match ty with
-  | Adt (Tuple, _) ->
+  | TAdt (TTuple, _) ->
       (* Tuple *)
       "(" ^ String.concat ", " field_values ^ ")"
-  | Adt (AdtId def_id, _) ->
+  | TAdt (TAdtId def_id, _) ->
       (* "Regular" ADT *)
       let adt_ident =
         match variant_id with
-        | Some vid -> fmt.adt_variant_to_string def_id vid
-        | None -> fmt.type_decl_id_to_string def_id
+        | Some vid -> adt_variant_from_type_decl_id_to_string env def_id vid
+        | None -> type_decl_id_to_string env def_id
       in
       if field_values <> [] then
-        match fmt.adt_field_names def_id variant_id with
+        match adt_field_names env def_id variant_id with
         | None ->
             let field_values = String.concat ", " field_values in
             adt_ident ^ " (" ^ field_values ^ ")"
@@ -462,13 +380,13 @@ let adt_g_value_to_string (fmt : value_formatter)
             let field_values = String.concat " " field_values in
             adt_ident ^ " { " ^ field_values ^ " }"
       else adt_ident
-  | Adt (Assumed aty, _) -> (
+  | TAdt (TAssumed aty, _) -> (
       (* Assumed type *)
       match aty with
-      | State | RawPtr _ ->
+      | TState | TRawPtr _ ->
           (* This type is opaque: we can't get there *)
           raise (Failure "Unreachable")
-      | Result ->
+      | TResult ->
           let variant_id = Option.get variant_id in
           if variant_id = result_return_id then
             match field_values with
@@ -480,13 +398,13 @@ let adt_g_value_to_string (fmt : value_formatter)
             | _ -> raise (Failure "Result::Fail takes exactly one value")
           else
             raise (Failure "Unreachable: improper variant id for result type")
-      | Error ->
+      | TError ->
           assert (field_values = []);
           let variant_id = Option.get variant_id in
           if variant_id = error_failure_id then "@Error::Failure"
           else if variant_id = error_out_of_fuel_id then "@Error::OutOfFuel"
           else raise (Failure "Unreachable: improper variant id for error type")
-      | Fuel ->
+      | TFuel ->
           let variant_id = Option.get variant_id in
           if variant_id = fuel_zero_id then (
             assert (field_values = []);
@@ -496,7 +414,7 @@ let adt_g_value_to_string (fmt : value_formatter)
             | [ v ] -> "@Fuel::Succ " ^ v
             | _ -> raise (Failure "@Fuel::Succ takes exactly one value")
           else raise (Failure "Unreachable: improper variant id for fuel type")
-      | Array | Slice | Str ->
+      | TArray | TSlice | TStr ->
           assert (variant_id = None);
           let field_values =
             List.mapi (fun i v -> string_of_int i ^ " -> " ^ v) field_values
@@ -504,42 +422,38 @@ let adt_g_value_to_string (fmt : value_formatter)
           let id = assumed_ty_to_string aty in
           id ^ " [" ^ String.concat "; " field_values ^ "]")
   | _ ->
-      let fmt = value_to_type_formatter fmt in
       raise
         (Failure
            ("Inconsistently typed value: expected ADT type but found:"
-          ^ "\n- ty: " ^ ty_to_string fmt false ty ^ "\n- variant_id: "
+          ^ "\n- ty: " ^ ty_to_string env false ty ^ "\n- variant_id: "
            ^ Print.option_to_string VariantId.to_string variant_id))
 
-let rec typed_pattern_to_string (fmt : ast_formatter) (v : typed_pattern) :
-    string =
+let rec typed_pattern_to_string (env : fmt_env) (v : typed_pattern) : string =
   match v.value with
   | PatConstant cv -> literal_to_string cv
-  | PatVar (v, None) -> var_to_string (ast_to_type_formatter fmt) v
+  | PatVar (v, None) -> var_to_string env v
   | PatVar (v, Some mp) ->
-      let mp = "[@mplace=" ^ mplace_to_string fmt mp ^ "]" in
+      let mp = "[@mplace=" ^ mplace_to_string env mp ^ "]" in
       "(" ^ var_to_varname v ^ " " ^ mp ^ " : "
-      ^ ty_to_string (ast_to_type_formatter fmt) false v.ty
+      ^ ty_to_string env false v.ty
       ^ ")"
   | PatDummy -> "_"
   | PatAdt av ->
-      adt_g_value_to_string
-        (ast_to_value_formatter fmt)
-        (typed_pattern_to_string fmt)
+      adt_g_value_to_string env
+        (typed_pattern_to_string env)
         av.variant_id av.field_values v.ty
 
-let fun_sig_to_string (fmt : ast_formatter) (sg : fun_sig) : string =
-  let ty_fmt = ast_to_type_formatter fmt in
-  let generics = generic_params_to_strings ty_fmt sg.generics in
-  let inputs = List.map (ty_to_string ty_fmt false) sg.inputs in
-  let output = ty_to_string ty_fmt false sg.output in
+let fun_sig_to_string (env : fmt_env) (sg : fun_sig) : string =
+  let env = { env with generics = sg.generics } in
+  let generics = generic_params_to_strings env sg.generics in
+  let inputs = List.map (ty_to_string env false) sg.inputs in
+  let output = ty_to_string env false sg.output in
   let all_types = List.concat [ generics; inputs; [ output ] ] in
   String.concat " -> " all_types
 
-let inst_fun_sig_to_string (fmt : ast_formatter) (sg : inst_fun_sig) : string =
-  let ty_fmt = ast_to_type_formatter fmt in
-  let inputs = List.map (ty_to_string ty_fmt false) sg.inputs in
-  let output = ty_to_string ty_fmt false sg.output in
+let inst_fun_sig_to_string (env : fmt_env) (sg : inst_fun_sig) : string =
+  let inputs = List.map (ty_to_string env false) sg.inputs in
+  let output = ty_to_string env false sg.output in
   let all_types = List.append inputs [ output ] in
   String.concat " -> " all_types
 
@@ -568,10 +482,14 @@ let llbc_assumed_fun_id_to_string (fid : A.assumed_fun_id) : string =
   | ArrayToSliceShared -> "@ArrayToSliceShared"
   | ArrayToSliceMut -> "@ArrayToSliceMut"
   | ArrayRepeat -> "@ArrayRepeat"
-  | SliceLen -> "@SliceLen"
   | SliceIndexShared -> "@SliceIndexShared"
   | SliceIndexMut -> "@SliceIndexMut"
 
+let llbc_fun_id_to_string (env : fmt_env) (fid : A.fun_id) : string =
+  match fid with
+  | FRegular fid -> fun_decl_id_to_string env fid
+  | FAssumed fid -> llbc_assumed_fun_id_to_string fid
+
 let pure_assumed_fun_id_to_string (fid : pure_assumed_fun_id) : string =
   match fid with
   | Return -> "return"
@@ -580,16 +498,15 @@ let pure_assumed_fun_id_to_string (fid : pure_assumed_fun_id) : string =
   | FuelDecrease -> "fuel_decrease"
   | FuelEqZero -> "fuel_eq_zero"
 
-let regular_fun_id_to_string (fmt : ast_formatter) (fun_id : fun_id) : string =
+let regular_fun_id_to_string (env : fmt_env) (fun_id : fun_id) : string =
   match fun_id with
   | FromLlbc (fid, lp_id, rg_id) ->
       let f =
         match fid with
-        | FunId (Regular fid) -> fmt.fun_decl_id_to_string fid
-        | FunId (Assumed fid) -> llbc_assumed_fun_id_to_string fid
+        | FunId (FRegular fid) -> fun_decl_id_to_string env fid
+        | FunId (FAssumed fid) -> llbc_assumed_fun_id_to_string fid
         | TraitMethod (trait_ref, method_name, _) ->
-            let fmt = ast_to_type_formatter fmt in
-            trait_ref_to_string fmt true trait_ref ^ "." ^ method_name
+            trait_ref_to_string env true trait_ref ^ "." ^ method_name
       in
       f ^ fun_suffix lp_id rg_id
   | Pure fid -> pure_assumed_fun_id_to_string fid
@@ -604,85 +521,84 @@ let unop_to_string (unop : unop) : string =
 
 let binop_to_string = Print.Expressions.binop_to_string
 
-let fun_or_op_id_to_string (fmt : ast_formatter) (fun_id : fun_or_op_id) :
-    string =
+let fun_or_op_id_to_string (env : fmt_env) (fun_id : fun_or_op_id) : string =
   match fun_id with
-  | Fun fun_id -> regular_fun_id_to_string fmt fun_id
+  | Fun fun_id -> regular_fun_id_to_string env fun_id
   | Unop unop -> unop_to_string unop
   | Binop (binop, int_ty) ->
       binop_to_string binop ^ "<" ^ integer_type_to_string int_ty ^ ">"
 
 (** [inside]: controls the introduction of parentheses *)
-let rec texpression_to_string (fmt : ast_formatter) (inside : bool)
-    (indent : string) (indent_incr : string) (e : texpression) : string =
+let rec texpression_to_string (env : fmt_env) (inside : bool) (indent : string)
+    (indent_incr : string) (e : texpression) : string =
   match e.e with
-  | Var var_id -> fmt.var_id_to_string var_id
-  | CVar cg_id -> fmt.const_generic_var_id_to_string cg_id
+  | Var var_id -> var_id_to_string env var_id
+  | CVar cg_id -> const_generic_var_id_to_string env cg_id
   | Const cv -> literal_to_string cv
   | App _ ->
       (* Recursively destruct the app, to have a pair (app, arguments list) *)
       let app, args = destruct_apps e in
       (* Convert to string *)
-      app_to_string fmt inside indent indent_incr app args
+      app_to_string env inside indent indent_incr app args
   | Abs _ ->
       let xl, e = destruct_abs_list e in
-      let e = abs_to_string fmt indent indent_incr xl e in
+      let e = abs_to_string env indent indent_incr xl e in
       if inside then "(" ^ e ^ ")" else e
   | Qualif _ ->
       (* Qualifier without arguments *)
-      app_to_string fmt inside indent indent_incr e []
+      app_to_string env inside indent indent_incr e []
   | Let (monadic, lv, re, e) ->
-      let e = let_to_string fmt indent indent_incr monadic lv re e in
+      let e = let_to_string env indent indent_incr monadic lv re e in
       if inside then "(" ^ e ^ ")" else e
   | Switch (scrutinee, body) ->
-      let e = switch_to_string fmt indent indent_incr scrutinee body in
+      let e = switch_to_string env indent indent_incr scrutinee body in
       if inside then "(" ^ e ^ ")" else e
   | Loop loop ->
-      let e = loop_to_string fmt indent indent_incr loop in
+      let e = loop_to_string env indent indent_incr loop in
       if inside then "(" ^ e ^ ")" else e
   | StructUpdate supd -> (
       let s =
         match supd.init with
         | None -> ""
-        | Some vid -> " " ^ fmt.var_id_to_string vid ^ " with"
+        | Some vid -> " " ^ var_id_to_string env vid ^ " with"
       in
       let indent1 = indent ^ indent_incr in
       let indent2 = indent1 ^ indent_incr in
       (* The id should be a custom type decl id or an array *)
       match supd.struct_id with
-      | AdtId aid ->
-          let field_names = Option.get (fmt.adt_field_names aid None) in
+      | TAdtId aid ->
+          let field_names = Option.get (adt_field_names env aid None) in
           let fields =
             List.map
               (fun (fid, fe) ->
                 let field = FieldId.nth field_names fid in
                 let fe =
-                  texpression_to_string fmt false indent2 indent_incr fe
+                  texpression_to_string env false indent2 indent_incr fe
                 in
                 "\n" ^ indent1 ^ field ^ " := " ^ fe ^ ";")
               supd.updates
           in
           let bl = if fields = [] then "" else "\n" ^ indent in
           "{" ^ s ^ String.concat "" fields ^ bl ^ "}"
-      | Assumed Array ->
+      | TAssumed TArray ->
           let fields =
             List.map
               (fun (_, fe) ->
-                texpression_to_string fmt false indent2 indent_incr fe)
+                texpression_to_string env false indent2 indent_incr fe)
               supd.updates
           in
           "[ " ^ String.concat ", " fields ^ " ]"
       | _ -> raise (Failure "Unexpected"))
   | Meta (meta, e) -> (
-      let meta_s = meta_to_string fmt meta in
-      let e = texpression_to_string fmt inside indent indent_incr e in
+      let meta_s = emeta_to_string env meta in
+      let e = texpression_to_string env inside indent indent_incr e in
       match meta with
       | Assignment _ | SymbolicAssignment _ | Tag _ ->
           let e = meta_s ^ "\n" ^ indent ^ e in
           if inside then "(" ^ e ^ ")" else e
       | MPlace _ -> "(" ^ meta_s ^ " " ^ e ^ ")")
 
-and app_to_string (fmt : ast_formatter) (inside : bool) (indent : string)
+and app_to_string (env : fmt_env) (inside : bool) (indent : string)
     (indent_incr : string) (app : texpression) (args : texpression list) :
     string =
   (* There are two possibilities: either the [app] is an instantiated,
@@ -692,40 +608,37 @@ and app_to_string (fmt : ast_formatter) (inside : bool) (indent : string)
     match app.e with
     | Qualif qualif ->
         (* Qualifier case *)
-        let ty_fmt = ast_to_type_formatter fmt in
         (* Convert the qualifier identifier *)
         let qualif_s =
           match qualif.id with
-          | FunOrOp fun_id -> fun_or_op_id_to_string fmt fun_id
-          | Global global_id -> fmt.global_decl_id_to_string global_id
+          | FunOrOp fun_id -> fun_or_op_id_to_string env fun_id
+          | Global global_id -> global_decl_id_to_string env global_id
           | AdtCons adt_cons_id ->
               let variant_s =
-                adt_variant_to_string
-                  (ast_to_value_formatter fmt)
-                  adt_cons_id.adt_id adt_cons_id.variant_id
+                adt_variant_to_string env adt_cons_id.adt_id
+                  adt_cons_id.variant_id
               in
               ConstStrings.constructor_prefix ^ variant_s
           | Proj { adt_id; field_id } ->
-              let value_fmt = ast_to_value_formatter fmt in
-              let adt_s = adt_variant_to_string value_fmt adt_id None in
-              let field_s = adt_field_to_string value_fmt adt_id field_id in
+              let adt_s = adt_variant_to_string env adt_id None in
+              let field_s = adt_field_to_string env adt_id field_id in
               (* Adopting an F*-like syntax *)
               ConstStrings.constructor_prefix ^ adt_s ^ "?." ^ field_s
           | TraitConst (trait_ref, generics, const_name) ->
-              let trait_ref = trait_ref_to_string ty_fmt true trait_ref in
-              let generics_s = generic_args_to_string ty_fmt generics in
+              let trait_ref = trait_ref_to_string env true trait_ref in
+              let generics_s = generic_args_to_string env generics in
               if generics <> empty_generic_args then
                 "(" ^ trait_ref ^ generics_s ^ ")." ^ const_name
               else trait_ref ^ "." ^ const_name
         in
         (* Convert the type instantiation *)
-        let generics = generic_args_to_strings ty_fmt true qualif.generics in
+        let generics = generic_args_to_strings env true qualif.generics in
         (* *)
         (qualif_s, generics)
     | _ ->
         (* "Regular" expression case *)
         let inside = args <> [] || (args = [] && inside) in
-        (texpression_to_string fmt inside indent indent_incr app, [])
+        (texpression_to_string env inside indent indent_incr app, [])
   in
   (* Convert the arguments.
    * The arguments are expressions, so indentation might get weird... (though
@@ -733,7 +646,7 @@ and app_to_string (fmt : ast_formatter) (inside : bool) (indent : string)
   let arg_to_string =
     let inside = true in
     let indent1 = indent ^ indent_incr in
-    texpression_to_string fmt inside indent1 indent_incr
+    texpression_to_string env inside indent1 indent_incr
   in
   let args = List.map arg_to_string args in
   let all_args = List.append generics args in
@@ -744,32 +657,31 @@ and app_to_string (fmt : ast_formatter) (inside : bool) (indent : string)
   (* Add parentheses *)
   if all_args <> [] && inside then "(" ^ e ^ ")" else e
 
-and abs_to_string (fmt : ast_formatter) (indent : string) (indent_incr : string)
+and abs_to_string (env : fmt_env) (indent : string) (indent_incr : string)
     (xl : typed_pattern list) (e : texpression) : string =
-  let xl = List.map (typed_pattern_to_string fmt) xl in
-  let e = texpression_to_string fmt false indent indent_incr e in
+  let xl = List.map (typed_pattern_to_string env) xl in
+  let e = texpression_to_string env false indent indent_incr e in
   "λ " ^ String.concat " " xl ^ ". " ^ e
 
-and let_to_string (fmt : ast_formatter) (indent : string) (indent_incr : string)
+and let_to_string (env : fmt_env) (indent : string) (indent_incr : string)
     (monadic : bool) (lv : typed_pattern) (re : texpression) (e : texpression) :
     string =
   let indent1 = indent ^ indent_incr in
   let inside = false in
-  let re = texpression_to_string fmt inside indent1 indent_incr re in
-  let e = texpression_to_string fmt inside indent indent_incr e in
-  let lv = typed_pattern_to_string fmt lv in
+  let re = texpression_to_string env inside indent1 indent_incr re in
+  let e = texpression_to_string env inside indent indent_incr e in
+  let lv = typed_pattern_to_string env lv in
   if monadic then lv ^ " <-- " ^ re ^ ";\n" ^ indent ^ e
   else "let " ^ lv ^ " = " ^ re ^ " in\n" ^ indent ^ e
 
-and switch_to_string (fmt : ast_formatter) (indent : string)
-    (indent_incr : string) (scrutinee : texpression) (body : switch_body) :
-    string =
+and switch_to_string (env : fmt_env) (indent : string) (indent_incr : string)
+    (scrutinee : texpression) (body : switch_body) : string =
   let indent1 = indent ^ indent_incr in
   (* Printing can mess up on the scrutinee, because it is an expression - but
    * in most situations it will be a value or a function call, so it should be
    * ok*)
-  let scrut = texpression_to_string fmt true indent1 indent_incr scrutinee in
-  let e_to_string = texpression_to_string fmt false indent1 indent_incr in
+  let scrut = texpression_to_string env true indent1 indent_incr scrutinee in
+  let e_to_string = texpression_to_string env false indent1 indent_incr in
   match body with
   | If (e_true, e_false) ->
       let e_true = e_to_string e_true in
@@ -778,79 +690,74 @@ and switch_to_string (fmt : ast_formatter) (indent : string)
       ^ indent ^ "else\n" ^ indent1 ^ e_false
   | Match branches ->
       let branch_to_string (b : match_branch) : string =
-        let pat = typed_pattern_to_string fmt b.pat in
+        let pat = typed_pattern_to_string env b.pat in
         indent ^ "| " ^ pat ^ " ->\n" ^ indent1 ^ e_to_string b.branch
       in
       let branches = List.map branch_to_string branches in
       "match " ^ scrut ^ " with\n" ^ String.concat "\n" branches
 
-and loop_to_string (fmt : ast_formatter) (indent : string)
-    (indent_incr : string) (loop : loop) : string =
+and loop_to_string (env : fmt_env) (indent : string) (indent_incr : string)
+    (loop : loop) : string =
   let indent1 = indent ^ indent_incr in
   let indent2 = indent1 ^ indent_incr in
-  let type_fmt = ast_to_type_formatter fmt in
   let loop_inputs =
     "fresh_vars: ["
-    ^ String.concat "; " (List.map (var_to_string type_fmt) loop.inputs)
+    ^ String.concat "; " (List.map (var_to_string env) loop.inputs)
     ^ "]"
   in
   let back_output_tys =
     let tys =
       match loop.back_output_tys with
       | None -> ""
-      | Some tys ->
-          String.concat "; "
-            (List.map (ty_to_string (ast_to_type_formatter fmt) false) tys)
+      | Some tys -> String.concat "; " (List.map (ty_to_string env false) tys)
     in
     "back_output_tys: [" ^ tys ^ "]"
   in
   let fun_end =
-    texpression_to_string fmt false indent2 indent_incr loop.fun_end
+    texpression_to_string env false indent2 indent_incr loop.fun_end
   in
   let loop_body =
-    texpression_to_string fmt false indent2 indent_incr loop.loop_body
+    texpression_to_string env false indent2 indent_incr loop.loop_body
   in
   "loop {\n" ^ indent1 ^ loop_inputs ^ "\n" ^ indent1 ^ back_output_tys ^ "\n"
   ^ indent1 ^ "fun_end: {\n" ^ indent2 ^ fun_end ^ "\n" ^ indent1 ^ "}\n"
   ^ indent1 ^ "loop_body: {\n" ^ indent2 ^ loop_body ^ "\n" ^ indent1 ^ "}\n"
   ^ indent ^ "}"
 
-and meta_to_string (fmt : ast_formatter) (meta : meta) : string =
+and emeta_to_string (env : fmt_env) (meta : emeta) : string =
   let meta =
     match meta with
     | Assignment (lp, rv, rp) ->
         let rp =
           match rp with
           | None -> ""
-          | Some rp -> " [@src=" ^ mplace_to_string fmt rp ^ "]"
+          | Some rp -> " [@src=" ^ mplace_to_string env rp ^ "]"
         in
-        "@assign(" ^ mplace_to_string fmt lp ^ " := "
-        ^ texpression_to_string fmt false "" "" rv
+        "@assign(" ^ mplace_to_string env lp ^ " := "
+        ^ texpression_to_string env false "" "" rv
         ^ rp ^ ")"
     | SymbolicAssignment (var_id, rv) ->
         "@symb_assign(" ^ VarId.to_string var_id ^ " := "
-        ^ texpression_to_string fmt false "" "" rv
+        ^ texpression_to_string env false "" "" rv
         ^ ")"
-    | MPlace mp -> "@mplace=" ^ mplace_to_string fmt mp
+    | MPlace mp -> "@mplace=" ^ mplace_to_string env mp
     | Tag msg -> "@tag \"" ^ msg ^ "\""
   in
   "@meta[" ^ meta ^ "]"
 
-let fun_decl_to_string (fmt : ast_formatter) (def : fun_decl) : string =
-  let type_fmt = ast_to_type_formatter fmt in
-  let name =
-    fun_name_to_string def.basename ^ fun_suffix def.loop_id def.back_id
-  in
-  let signature = fun_sig_to_string fmt def.signature in
+let fun_decl_to_string (env : fmt_env) (def : fun_decl) : string =
+  let env = { env with generics = def.signature.generics } in
+  let name = def.name ^ fun_suffix def.loop_id def.back_id in
+  let signature = fun_sig_to_string env def.signature in
   match def.body with
   | None -> "val " ^ name ^ " :\n  " ^ signature
   | Some body ->
       let inside = false in
       let indent = "  " in
-      let inputs = List.map (var_to_string type_fmt) body.inputs in
+      let inputs = List.map (var_to_string env) body.inputs in
       let inputs =
         if inputs = [] then indent
         else "  fun " ^ String.concat " " inputs ^ " ->\n" ^ indent
       in
-      let body = texpression_to_string fmt inside indent indent body.body in
+      let body = texpression_to_string env inside indent indent body.body in
       "let " ^ name ^ " :\n  " ^ signature ^ " =\n" ^ inputs ^ body
diff --git a/compiler/Pure.ml b/compiler/Pure.ml
index e6a3dab5..50849df9 100644
--- a/compiler/Pure.ml
+++ b/compiler/Pure.ml
@@ -1,6 +1,4 @@
 open Identifiers
-open Names
-module PV = PrimitiveValues
 module T = Types
 module V = Values
 module E = Expressions
@@ -16,6 +14,7 @@ module GlobalDeclId = A.GlobalDeclId
 module TraitDeclId = T.TraitDeclId
 module TraitImplId = T.TraitImplId
 module TraitClauseId = T.TraitClauseId
+module Disambiguator = T.Disambiguator
 
 (** We redefine identifiers for loop: in {!Values}, the identifiers are global
     (they monotonically increase across functions) while in {!module:Pure} we want
@@ -35,6 +34,7 @@ IdGen ()
 
 module ConstGenericVarId = T.ConstGenericVarId
 
+type llbc_name = T.name [@@deriving show, ord]
 type integer_type = T.integer_type [@@deriving show, ord]
 type const_generic_var = T.const_generic_var [@@deriving show, ord]
 type const_generic = T.const_generic [@@deriving show, ord]
@@ -48,6 +48,10 @@ type fun_decl_id = A.fun_decl_id [@@deriving show, ord]
 type loop_id = LoopId.id [@@deriving show, ord]
 type region_group_id = T.region_group_id [@@deriving show, ord]
 type mutability = Mut | Const [@@deriving show, ord]
+type loc = Meta.loc [@@deriving show, ord]
+type file_name = Meta.file_name [@@deriving show, ord]
+type span = Meta.span [@@deriving show, ord]
+type meta = Meta.meta [@@deriving show, ord]
 
 (** The assumed types for the pure AST.
 
@@ -64,16 +68,18 @@ type mutability = Mut | Const [@@deriving show, ord]
       - [State]: the type of the state, when using state-error monads. Note that
         this state is opaque to Aeneas (the user can define it, or leave it as
         assumed)
+
+    TODO: add a prefix "T"
   *)
 type assumed_ty =
-  | State
-  | Result
-  | Error
-  | Fuel
-  | Array
-  | Slice
-  | Str
-  | RawPtr of mutability
+  | TState
+  | TResult
+  | TError
+  | TFuel
+  | TArray
+  | TSlice
+  | TStr
+  | TRawPtr of mutability
       (** The bool
           Raw pointers don't make sense in the pure world, but we don't know
           how to translate them yet and we have to handle some functions which
@@ -144,7 +150,7 @@ class virtual ['self] mapreduce_type_id_base =
       fun _ x -> (x, self#zero)
   end
 
-type type_id = AdtId of type_decl_id | Tuple | Assumed of assumed_ty
+type type_id = TAdtId of type_decl_id | TTuple | TAssumed of assumed_ty
 [@@deriving
   show,
     ord,
@@ -190,7 +196,6 @@ class ['self] iter_ty_base =
   object (_self : 'self)
     inherit [_] iter_type_id
     inherit! [_] T.iter_const_generic
-    inherit! [_] PV.iter_literal_type
     method visit_type_var_id : 'env -> type_var_id -> unit = fun _ _ -> ()
     method visit_trait_decl_id : 'env -> trait_decl_id -> unit = fun _ _ -> ()
     method visit_trait_impl_id : 'env -> trait_impl_id -> unit = fun _ _ -> ()
@@ -207,7 +212,6 @@ class ['self] map_ty_base =
   object (_self : 'self)
     inherit [_] map_type_id
     inherit! [_] T.map_const_generic
-    inherit! [_] PV.map_literal_type
     method visit_type_var_id : 'env -> type_var_id -> type_var_id = fun _ x -> x
 
     method visit_trait_decl_id : 'env -> trait_decl_id -> trait_decl_id =
@@ -228,7 +232,6 @@ class virtual ['self] reduce_ty_base =
   object (self : 'self)
     inherit [_] reduce_type_id
     inherit! [_] T.reduce_const_generic
-    inherit! [_] PV.reduce_literal_type
     method visit_type_var_id : 'env -> type_var_id -> 'a = fun _ _ -> self#zero
 
     method visit_trait_decl_id : 'env -> trait_decl_id -> 'a =
@@ -249,7 +252,6 @@ class virtual ['self] mapreduce_ty_base =
   object (self : 'self)
     inherit [_] mapreduce_type_id
     inherit! [_] T.mapreduce_const_generic
-    inherit! [_] PV.mapreduce_literal_type
 
     method visit_type_var_id : 'env -> type_var_id -> type_var_id * 'a =
       fun _ x -> (x, self#zero)
@@ -270,7 +272,7 @@ class virtual ['self] mapreduce_ty_base =
   end
 
 type ty =
-  | Adt of type_id * generic_args
+  | TAdt of type_id * generic_args
       (** {!Adt} encodes ADTs and tuples and assumed types.
 
           TODO: what about the ended regions? (ADTs may be parameterized
@@ -278,10 +280,10 @@ type ty =
           be able to only give back part of the ADT. We need a way to encode
           such "partial" ADTs.
        *)
-  | TypeVar of type_var_id
-  | Literal of literal_type
-  | Arrow of ty * ty
-  | TraitType of trait_ref * generic_args * string
+  | TVar of type_var_id
+  | TLiteral of literal_type
+  | TArrow of ty * ty
+  | TTraitType of trait_ref * generic_args * string
       (** The string is for the name of the associated type *)
 
 and trait_ref = {
@@ -383,8 +385,22 @@ type predicates = { trait_type_constraints : trait_type_constraint list }
 
 type type_decl = {
   def_id : TypeDeclId.id;
-  name : name;
+  is_local : bool;
+  llbc_name : llbc_name;
+      (** The original name coming from the LLBC declaration *)
+  name : string;
+      (** We use the name only for printing purposes (for debugging):
+          the name used at extraction time will be derived from the
+          llbc_name.
+       *)
+  meta : meta;
   generics : generic_params;
+  llbc_generics : Types.generic_params;
+      (** We use the LLBC generics to generate "pretty" names, for instance
+          for the variables we introduce for the trait clauses: we derive
+          those names from the types, and when doing so it is more meaningful
+          to derive them from the original LLBC types from before the
+          simplification of types like boxes and references. *)
   kind : type_decl_kind;
   preds : predicates;
 }
@@ -712,7 +728,7 @@ type expression =
   | Switch of texpression * switch_body
   | Loop of loop  (** See the comments for {!loop} *)
   | StructUpdate of struct_update  (** See the comments for {!struct_update} *)
-  | Meta of (meta[@opaque]) * texpression  (** Meta-information *)
+  | Meta of (emeta[@opaque]) * texpression  (** Meta-information *)
 
 and switch_body = If of texpression * texpression | Match of match_branch list
 and match_branch = { pat : typed_pattern; branch : texpression }
@@ -731,6 +747,7 @@ and match_branch = { pat : typed_pattern; branch : texpression }
 and loop = {
   fun_end : texpression;
   loop_id : loop_id;
+  meta : meta; [@opaque]
   fuel0 : var_id;
   fuel : var_id;
   input_state : var_id option;
@@ -786,7 +803,7 @@ and texpression = { e : expression; ty : ty }
 and mvalue = (texpression[@opaque])
 
 (** Meta-information stored in the AST *)
-and meta =
+and emeta =
   | Assignment of mplace * mvalue * mplace option
       (** Information about an assignment which occured in LLBC.
           We use this to guide the heuristics which derive pretty names.
@@ -911,6 +928,12 @@ type fun_sig_info = {
 type fun_sig = {
   generics : generic_params;
       (** TODO: we should analyse the signature to make the type parameters implicit whenever possible *)
+  llbc_generics : Types.generic_params;
+      (** We use the LLBC generics to generate "pretty" names, for instance
+          for the variables we introduce for the trait clauses: we derive
+          those names from the types, and when doing so it is more meaningful
+          to derive them from the original LLBC types from before the
+          simplification of types like boxes and references. *)
   preds : predicates;
   inputs : ty list;
       (** The types of the inputs.
@@ -987,6 +1010,8 @@ type fun_kind = A.fun_kind [@@deriving show]
 
 type fun_decl = {
   def_id : FunDeclId.id;
+  is_local : bool;
+  meta : meta;
   kind : fun_kind;
   num_loops : int;
       (** The number of loops in the parent forward function (basically the number
@@ -996,11 +1021,11 @@ type fun_decl = {
   loop_id : LoopId.id option;
       (** [Some] if this definition was generated for a loop *)
   back_id : T.RegionGroupId.id option;
-  basename : fun_name;
-      (** The "base" name of the function.
-
-          The base name is the original name of the Rust function. We add suffixes
-          (to identify the forward/backward functions) later.
+  llbc_name : llbc_name;  (** The original LLBC name. *)
+  name : string;
+      (** We use the name only for printing purposes (for debugging):
+          the name used at extraction time will be derived from the
+          llbc_name.
        *)
   signature : fun_sig;
   is_global_decl_body : bool;
@@ -1010,10 +1035,20 @@ type fun_decl = {
 
 type trait_decl = {
   def_id : trait_decl_id;
-  name : name;
+  is_local : bool;
+  llbc_name : llbc_name;
+  name : string;
+  meta : meta;
   generics : generic_params;
+  llbc_generics : Types.generic_params;
+      (** We use the LLBC generics to generate "pretty" names, for instance
+          for the variables we introduce for the trait clauses: we derive
+          those names from the types, and when doing so it is more meaningful
+          to derive them from the original LLBC types from before the
+          simplification of types like boxes and references. *)
   preds : predicates;
   parent_clauses : trait_clause list;
+  llbc_parent_clauses : Types.trait_clause list;
   consts : (trait_item_name * (ty * global_decl_id option)) list;
   types : (trait_item_name * (trait_clause list * ty option)) list;
   required_methods : (trait_item_name * fun_decl_id) list;
@@ -1023,9 +1058,20 @@ type trait_decl = {
 
 type trait_impl = {
   def_id : trait_impl_id;
-  name : name;
+  is_local : bool;
+  llbc_name : llbc_name;
+  name : string;
+  meta : meta;
   impl_trait : trait_decl_ref;
+  llbc_impl_trait : Types.trait_decl_ref;
+      (** Same remark as for {llbc_generics}. *)
   generics : generic_params;
+  llbc_generics : Types.generic_params;
+      (** We use the LLBC generics to generate "pretty" names, for instance
+          for the variables we introduce for the trait clauses: we derive
+          those names from the types, and when doing so it is more meaningful
+          to derive them from the original LLBC types from before the
+          simplification of types like boxes and references. *)
   preds : predicates;
   parent_trait_refs : trait_ref list;
   consts : (trait_item_name * (ty * global_decl_id)) list;
diff --git a/compiler/PureMicroPasses.ml b/compiler/PureMicroPasses.ml
index f3e6cbe2..d0741b29 100644
--- a/compiler/PureMicroPasses.ml
+++ b/compiler/PureMicroPasses.ml
@@ -3,10 +3,13 @@
 open Pure
 open PureUtils
 open TranslateCore
-module V = Values
 
 (** The local logger *)
-let log = L.pure_micro_passes_log
+let log = Logging.pure_micro_passes_log
+
+let fun_decl_to_string (ctx : trans_ctx) (def : Pure.fun_decl) : string =
+  let fmt = trans_ctx_to_pure_fmt_env ctx in
+  PrintPure.fun_decl_to_string fmt def
 
 (** Small utility.
 
@@ -388,7 +391,7 @@ let compute_pretty_names (def : fun_decl) : fun_decl =
       | Switch (scrut, body) -> update_switch_body scrut body ctx
       | Loop loop -> update_loop loop ctx
       | StructUpdate supd -> update_struct_update supd ctx
-      | Meta (meta, e) -> update_meta meta e ctx
+      | Meta (meta, e) -> update_emeta meta e ctx
     in
     (ctx, { e; ty })
   (* *)
@@ -446,6 +449,7 @@ let compute_pretty_names (def : fun_decl) : fun_decl =
     let {
       fun_end;
       loop_id;
+      meta;
       fuel0;
       fuel;
       input_state;
@@ -464,6 +468,7 @@ let compute_pretty_names (def : fun_decl) : fun_decl =
       {
         fun_end;
         loop_id;
+        meta;
         fuel0;
         fuel;
         input_state;
@@ -487,7 +492,7 @@ let compute_pretty_names (def : fun_decl) : fun_decl =
     let supd = { struct_id; init; updates } in
     (ctx, StructUpdate supd)
   (* *)
-  and update_meta (meta : meta) (e : texpression) (ctx : pn_ctx) :
+  and update_emeta (meta : emeta) (e : texpression) (ctx : pn_ctx) :
       pn_ctx * expression =
     let ctx =
       match meta with
@@ -513,7 +518,7 @@ let compute_pretty_names (def : fun_decl) : fun_decl =
       | Tag _ -> ctx
     in
     let ctx, e = update_texpression e ctx in
-    let e = mk_meta meta e in
+    let e = mk_emeta meta e in
     (ctx, e.e)
   in
 
@@ -582,7 +587,7 @@ let intro_struct_updates (ctx : trans_ctx) (def : fun_decl) : fun_decl =
             match app.e with
             | Qualif
                 {
-                  id = AdtCons { adt_id = AdtId adt_id; variant_id = None };
+                  id = AdtCons { adt_id = TAdtId adt_id; variant_id = None };
                   generics = _;
                 } ->
                 (* Lookup the def *)
@@ -597,8 +602,8 @@ let intro_struct_updates (ctx : trans_ctx) (def : fun_decl) : fun_decl =
                     match
                       TypeDeclId.Map.find adt_id ctx.type_ctx.type_decls_groups
                     with
-                    | NonRec _ -> false
-                    | Rec _ -> true
+                    | NonRecGroup _ -> false
+                    | RecGroup _ -> true
                   in
                   (* Convert, if possible - note that for now for Lean and Coq
                      we don't support the structure syntax on recursive structures *)
@@ -606,7 +611,7 @@ let intro_struct_updates (ctx : trans_ctx) (def : fun_decl) : fun_decl =
                     (!Config.backend <> Lean && !Config.backend <> Coq)
                     || not is_rec
                   then
-                    let struct_id = AdtId adt_id in
+                    let struct_id = TAdtId adt_id in
                     let init = None in
                     let updates =
                       FieldId.mapi
@@ -786,18 +791,19 @@ let expression_contains_child_call_in_all_paths (ctx : trans_ctx)
                 if rg_id0 = rg_id1 then true
                 else
                   (* We need to use the regions hierarchy *)
-                  (* First, lookup the signature of the LLBC function *)
-                  let sg =
+                  let regions_hierarchy =
                     let id0 =
                       match id0 with
                       | FunId fun_id -> fun_id
-                      | TraitMethod (_, _, fun_decl_id) -> Regular fun_decl_id
+                      | TraitMethod (_, _, fun_decl_id) -> FRegular fun_decl_id
                     in
-                    LlbcAstUtils.lookup_fun_sig id0 ctx.fun_ctx.fun_decls
+                    LlbcAstUtils.FunIdMap.find id0
+                      ctx.fun_ctx.regions_hierarchies
                   in
                   (* Compute the set of ancestors of the function in call1 *)
                   let call1_ancestors =
-                    LlbcAstUtils.list_ancestor_region_groups sg rg_id1
+                    LlbcAstUtils.list_ancestor_region_groups regions_hierarchy
+                      rg_id1
                   in
                   (* Check if the function used in call0 is inside *)
                   T.RegionGroupId.Set.mem rg_id0 call1_ancestors
@@ -1085,7 +1091,7 @@ let simplify_aggregates (ctx : trans_ctx) (def : fun_decl) : fun_decl =
             match app.e with
             | Qualif
                 {
-                  id = AdtCons { adt_id = AdtId adt_id; variant_id = None };
+                  id = AdtCons { adt_id = TAdtId adt_id; variant_id = None };
                   generics;
                 } ->
                 (* This is a struct *)
@@ -1114,7 +1120,7 @@ let simplify_aggregates (ctx : trans_ctx) (def : fun_decl) : fun_decl =
                         | ( Qualif
                               {
                                 id =
-                                  Proj { adt_id = AdtId proj_adt_id; field_id };
+                                  Proj { adt_id = TAdtId proj_adt_id; field_id };
                                 generics = proj_generics;
                               },
                             Var v ) ->
@@ -1157,13 +1163,13 @@ let simplify_aggregates (ctx : trans_ctx) (def : fun_decl) : fun_decl =
                   match (proj.e, x.e) with
                   | ( Qualif
                         {
-                          id = Proj { adt_id = AdtId proj_adt_id; field_id };
+                          id = Proj { adt_id = TAdtId proj_adt_id; field_id };
                           generics = _;
                         },
                       Var v ) ->
                       (* We check that this is the proper ADT, and the proper field *)
                       if
-                        AdtId proj_adt_id = struct_id
+                        TAdtId proj_adt_id = struct_id
                         && field_id = fid && x.ty = adt_ty
                       then Some v
                       else None
@@ -1246,6 +1252,7 @@ let filter_if_backward_with_no_outputs (def : fun_decl) : fun_decl option =
     !Config.filter_useless_functions
     && Option.is_some def.back_id
     && def.signature.output = mk_result_ty mk_unit_ty
+    || def.signature.output = mk_unit_ty
   then None
   else Some def
 
@@ -1357,6 +1364,7 @@ let decompose_loops (def : fun_decl) : fun_decl * fun_decl list =
             let loop_sig =
               {
                 generics = fun_sig.generics;
+                llbc_generics = fun_sig.llbc_generics;
                 preds = fun_sig.preds;
                 inputs = inputs_tys;
                 output;
@@ -1419,14 +1427,17 @@ let decompose_loops (def : fun_decl) : fun_decl * fun_decl list =
 
             let loop_body = { inputs; inputs_lvs; body = loop_body } in
 
-            let loop_def =
+            let loop_def : fun_decl =
               {
                 def_id = def.def_id;
+                is_local = def.is_local;
+                meta = loop.meta;
                 kind = def.kind;
                 num_loops;
                 loop_id = Some loop.loop_id;
                 back_id = def.back_id;
-                basename = def.basename;
+                llbc_name = def.llbc_name;
+                name = def.name;
                 signature = loop_sig;
                 is_global_decl_body = def.is_global_decl_body;
                 body = Some loop_body;
@@ -1503,8 +1514,8 @@ let unit_vars_to_unit (def : fun_decl) : fun_decl =
       let body = Some { body with body = body_exp; inputs_lvs } in
       { def with body }
 
-(** Eliminate the box functions like [Box::new], [Box::deref], etc. Most of them
-    are translated to identity, and [Box::free] is translated to [()].
+(** Eliminate the box functions like [Box::new] (which is translated to the
+    identity) and [Box::free] (which is translated to [()]).
 
     Note that the box types have already been eliminated during the translation
     from symbolic to pure.
@@ -1513,7 +1524,7 @@ let unit_vars_to_unit (def : fun_decl) : fun_decl =
     function calls, and when translating end abstractions. Here, we can do
     something simpler, in one micro-pass.
  *)
-let eliminate_box_functions (ctx : trans_ctx) (def : fun_decl) : fun_decl =
+let eliminate_box_functions (_ctx : trans_ctx) (def : fun_decl) : fun_decl =
   (* The map visitor *)
   let obj =
     object
@@ -1527,7 +1538,7 @@ let eliminate_box_functions (ctx : trans_ctx) (def : fun_decl) : fun_decl =
              * could have: [box_new f x])
              * *)
             match fun_id with
-            | Fun (FromLlbc (FunId (Assumed aid), _lp_id, rg_id)) -> (
+            | Fun (FromLlbc (FunId (FAssumed aid), _lp_id, rg_id)) -> (
                 match (aid, rg_id) with
                 | BoxNew, _ ->
                     assert (rg_id = None);
@@ -1538,38 +1549,9 @@ let eliminate_box_functions (ctx : trans_ctx) (def : fun_decl) : fun_decl =
                     mk_unit_rvalue
                 | ( ( SliceIndexShared | SliceIndexMut | ArrayIndexShared
                     | ArrayIndexMut | ArrayToSliceShared | ArrayToSliceMut
-                    | ArrayRepeat | SliceLen ),
+                    | ArrayRepeat ),
                     _ ) ->
                     super#visit_texpression env e)
-            | Fun (FromLlbc (FunId (Regular fid), _lp_id, rg_id)) -> (
-                (* Lookup the function name *)
-                let def = FunDeclId.Map.find fid ctx.fun_ctx.fun_decls in
-                match
-                  (Names.name_no_disambiguators_to_string def.name, rg_id)
-                with
-                | "alloc::boxed::Box::deref", None ->
-                    (* [Box::deref] forward is the identity *)
-                    let arg, args = Collections.List.pop args in
-                    mk_apps arg args
-                | "alloc::boxed::Box::deref", Some _ ->
-                    (* [Box::deref] backward is [()] (doesn't give back anything) *)
-                    assert (args = []);
-                    mk_unit_rvalue
-                | "alloc::boxed::Box::deref_mut", None ->
-                    (* [Box::deref_mut] forward is the identity *)
-                    let arg, args = Collections.List.pop args in
-                    mk_apps arg args
-                | "alloc::boxed::Box::deref_mut", Some _ ->
-                    (* [Box::deref_mut] back is almost the identity:
-                     * let box_deref_mut (x_init : t) (x_back : t) : t = x_back
-                     * *)
-                    let arg, args =
-                      match args with
-                      | _ :: given_back :: args -> (given_back, args)
-                      | _ -> raise (Failure "Unreachable")
-                    in
-                    mk_apps arg args
-                | _ -> super#visit_texpression env e)
             | _ -> super#visit_texpression env e)
         | _ -> super#visit_texpression env e
     end
@@ -1917,9 +1899,7 @@ let apply_passes_to_def (ctx : trans_ctx) (def : fun_decl) :
   (* Debug *)
   log#ldebug
     (lazy
-      ("PureMicroPasses.apply_passes_to_def: "
-      ^ Print.fun_name_to_string def.basename
-      ^ " ("
+      ("PureMicroPasses.apply_passes_to_def: " ^ def.name ^ " ("
       ^ Print.option_to_string T.RegionGroupId.to_string def.back_id
       ^ ")"));
 
@@ -1945,11 +1925,17 @@ let apply_passes_to_def (ctx : trans_ctx) (def : fun_decl) :
    * Note that the calls to those functions should already have been removed,
    * when translating from symbolic to pure. Here, we remove the definitions
    * altogether, because they are now useless *)
-  let def = filter_if_backward_with_no_outputs def in
+  let name = def.name ^ PrintPure.fun_suffix def.loop_id def.back_id in
+  let opt_def = filter_if_backward_with_no_outputs def in
 
-  match def with
-  | None -> None
+  match opt_def with
+  | None ->
+      log#ldebug (lazy ("filtered (backward with no outputs): " ^ name ^ "\n"));
+      None
   | Some def ->
+      log#ldebug
+        (lazy ("not filtered (not backward with no outputs): " ^ name ^ "\n"));
+
       (* Extract the loop definitions by removing the {!Loop} node *)
       let def, loops = decompose_loops def in
 
@@ -2050,7 +2036,7 @@ let filter_loop_inputs (transl : pure_fun_translation list) :
     let inputs_set = VarId.Set.of_list (List.map var_get_id inputs_prefix) in
     assert (Option.is_some decl.loop_id);
 
-    let fun_id = (E.Regular decl.def_id, decl.loop_id) in
+    let fun_id = (E.FRegular decl.def_id, decl.loop_id) in
 
     let set_used vid =
       used := List.map (fun (vid', b) -> (vid', b || vid = vid')) !used
@@ -2134,7 +2120,7 @@ let filter_loop_inputs (transl : pure_fun_translation list) :
   (* We then apply the filtering to all the function definitions at once *)
   let filter_in_one (decl : fun_decl) : fun_decl =
     (* Filter the function signature *)
-    let fun_id = (E.Regular decl.def_id, decl.loop_id) in
+    let fun_id = (E.FRegular decl.def_id, decl.loop_id) in
     let decl =
       match FunLoopIdMap.find_opt fun_id !used_map with
       | None -> (* Nothing to filter *) decl
@@ -2142,7 +2128,8 @@ let filter_loop_inputs (transl : pure_fun_translation list) :
           let num_filtered =
             List.length (List.filter (fun b -> not b) used_info)
           in
-          let { generics; preds; inputs; output; doutputs; info } =
+          let { generics; llbc_generics; preds; inputs; output; doutputs; info }
+              =
             decl.signature
           in
           let {
@@ -2170,7 +2157,9 @@ let filter_loop_inputs (transl : pure_fun_translation list) :
               effect_info;
             }
           in
-          let signature = { generics; preds; inputs; output; doutputs; info } in
+          let signature =
+            { generics; llbc_generics; preds; inputs; output; doutputs; info }
+          in
 
           { decl with signature }
     in
diff --git a/compiler/PureTypeCheck.ml b/compiler/PureTypeCheck.ml
index 2ad942bb..a62a2361 100644
--- a/compiler/PureTypeCheck.ml
+++ b/compiler/PureTypeCheck.ml
@@ -12,41 +12,41 @@ let get_adt_field_types (type_decls : type_decl TypeDeclId.Map.t)
     (type_id : type_id) (variant_id : VariantId.id option)
     (generics : generic_args) : ty list =
   match type_id with
-  | Tuple ->
+  | TTuple ->
       (* Tuple *)
       assert (generics.const_generics = []);
       assert (generics.trait_refs = []);
       assert (variant_id = None);
       generics.types
-  | AdtId def_id ->
+  | TAdtId def_id ->
       (* "Regular" ADT *)
       let def = TypeDeclId.Map.find def_id type_decls in
       type_decl_get_instantiated_fields_types def variant_id generics
-  | Assumed aty -> (
+  | TAssumed aty -> (
       (* Assumed type *)
       match aty with
-      | State ->
+      | TState ->
           (* This type is opaque *)
           raise (Failure "Unreachable: opaque type")
-      | Result ->
+      | TResult ->
           let ty = Collections.List.to_cons_nil generics.types in
           let variant_id = Option.get variant_id in
           if variant_id = result_return_id then [ ty ]
           else if variant_id = result_fail_id then [ mk_error_ty ]
           else
             raise (Failure "Unreachable: improper variant id for result type")
-      | Error ->
+      | TError ->
           assert (generics = empty_generic_args);
           let variant_id = Option.get variant_id in
           assert (
             variant_id = error_failure_id || variant_id = error_out_of_fuel_id);
           []
-      | Fuel ->
+      | TFuel ->
           let variant_id = Option.get variant_id in
           if variant_id = fuel_zero_id then []
           else if variant_id = fuel_succ_id then [ mk_fuel_ty ]
           else raise (Failure "Unreachable: improper variant id for fuel type")
-      | Array | Slice | Str | RawPtr _ ->
+      | TArray | TSlice | TStr | TRawPtr _ ->
           (* Array: when not symbolic values (for instance, because of aggregates),
              the array expressions are introduced as struct updates *)
           raise (Failure "Attempting to access the fields of an opaque type"))
@@ -63,8 +63,8 @@ type tc_ctx = {
 
 let check_literal (v : literal) (ty : literal_type) : unit =
   match (ty, v) with
-  | Integer int_ty, PV.Scalar sv -> assert (int_ty = sv.PV.int_ty)
-  | Bool, Bool _ | Char, Char _ -> ()
+  | TInteger int_ty, VScalar sv -> assert (int_ty = sv.int_ty)
+  | TBool, VBool _ | TChar, VChar _ -> ()
   | _ -> raise (Failure "Inconsistent type")
 
 let rec check_typed_pattern (ctx : tc_ctx) (v : typed_pattern) : tc_ctx =
@@ -156,7 +156,7 @@ let rec check_texpression (ctx : tc_ctx) (e : texpression) : unit =
           let field_tys, adt_ty = destruct_arrows e.ty in
           assert (expected_field_tys = field_tys);
           match adt_ty with
-          | Adt (type_id, generics) ->
+          | TAdt (type_id, generics) ->
               assert (type_id = id.adt_id);
               assert (generics = qualif.generics)
           | _ -> raise (Failure "Unreachable")))
@@ -174,7 +174,7 @@ let rec check_texpression (ctx : tc_ctx) (e : texpression) : unit =
       check_texpression ctx scrut;
       match switch_body with
       | If (e_then, e_else) ->
-          assert (scrut.ty = Literal Bool);
+          assert (scrut.ty = TLiteral TBool);
           assert (e_then.ty = e.ty);
           assert (e_else.ty = e.ty);
           check_texpression ctx e_then;
@@ -208,7 +208,7 @@ let rec check_texpression (ctx : tc_ctx) (e : texpression) : unit =
       assert (adt_id = supd.struct_id);
       (* The id can only be: a custom type decl or an array *)
       match adt_id with
-      | AdtId _ ->
+      | TAdtId _ ->
           let variant_id = None in
           let expected_field_tys =
             get_adt_field_types ctx.type_decls adt_id variant_id adt_generics
@@ -219,7 +219,7 @@ let rec check_texpression (ctx : tc_ctx) (e : texpression) : unit =
               assert (expected_field_ty = fe.ty);
               check_texpression ctx fe)
             supd.updates
-      | Assumed Array ->
+      | TAssumed TArray ->
           let expected_field_ty =
             Collections.List.to_cons_nil adt_generics.types
           in
diff --git a/compiler/PureUtils.ml b/compiler/PureUtils.ml
index 3aeabffe..6b0deb73 100644
--- a/compiler/PureUtils.ml
+++ b/compiler/PureUtils.ml
@@ -15,11 +15,11 @@ end
 module RegularFunIdMap = Collections.MakeMap (RegularFunIdOrderedType)
 
 (** We use this type as a key for lookups *)
-type regular_fun_id_not_loop = A.fun_id * T.RegionGroupId.id option
+type regular_fun_id_not_loop = LlbcAst.fun_id * RegionGroupId.id option
 [@@deriving show, ord]
 
 (** We use this type as a key for lookups *)
-type fun_loop_id = A.FunDeclId.id * LoopId.id option [@@deriving show, ord]
+type fun_loop_id = FunDeclId.id * LoopId.id option [@@deriving show, ord]
 
 module RegularFunIdNotLoopOrderedType = struct
   type t = regular_fun_id_not_loop
@@ -59,19 +59,19 @@ module FunLoopIdSet = Collections.MakeSet (FunLoopIdOrderedType)
 
 let dest_arrow_ty (ty : ty) : ty * ty =
   match ty with
-  | Arrow (arg_ty, ret_ty) -> (arg_ty, ret_ty)
+  | TArrow (arg_ty, ret_ty) -> (arg_ty, ret_ty)
   | _ -> raise (Failure "Unreachable")
 
 let compute_literal_type (cv : literal) : literal_type =
   match cv with
-  | PV.Scalar sv -> Integer sv.PV.int_ty
-  | Bool _ -> Bool
-  | Char _ -> Char
+  | VScalar sv -> TInteger sv.int_ty
+  | VBool _ -> TBool
+  | VChar _ -> TChar
 
 let var_get_id (v : var) : VarId.id = v.id
 
 let mk_typed_pattern_from_literal (cv : literal) : typed_pattern =
-  let ty = Literal (compute_literal_type cv) in
+  let ty = TLiteral (compute_literal_type cv) in
   { value = PatConstant cv; ty }
 
 let mk_let (monadic : bool) (lv : typed_pattern) (re : texpression)
@@ -110,8 +110,8 @@ let ty_substitute (subst : subst) (ty : ty) : ty =
   let obj =
     object
       inherit [_] map_ty
-      method! visit_TypeVar _ var_id = subst.ty_subst var_id
-      method! visit_ConstGenericVar _ var_id = subst.cg_subst var_id
+      method! visit_TVar _ var_id = subst.ty_subst var_id
+      method! visit_CgVar _ var_id = subst.cg_subst var_id
       method! visit_Clause _ id = subst.tr_subst id
       method! visit_Self _ = subst.tr_self
     end
@@ -232,7 +232,7 @@ let is_const (e : texpression) : bool =
 
 let ty_as_adt (ty : ty) : type_id * generic_args =
   match ty with
-  | Adt (id, generics) -> (id, generics)
+  | TAdt (id, generics) -> (id, generics)
   | _ -> raise (Failure "Unreachable")
 
 (** Remove the external occurrences of {!Meta} *)
@@ -249,12 +249,12 @@ let remove_meta (e : texpression) : texpression =
   in
   obj#visit_texpression () e
 
-let mk_arrow (ty0 : ty) (ty1 : ty) : ty = Arrow (ty0, ty1)
+let mk_arrow (ty0 : ty) (ty1 : ty) : ty = TArrow (ty0, ty1)
 
 (** Construct a type as a list of arrows: ty1 -> ... tyn  *)
 let mk_arrows (inputs : ty list) (output : ty) =
   let rec aux (tys : ty list) : ty =
-    match tys with [] -> output | ty :: tys' -> Arrow (ty, aux tys')
+    match tys with [] -> output | ty :: tys' -> TArrow (ty, aux tys')
   in
   aux inputs
 
@@ -305,7 +305,7 @@ let destruct_apps (e : texpression) : texpression * texpression list =
 (** Make an [App (app, arg)] expression *)
 let mk_app (app : texpression) (arg : texpression) : texpression =
   match app.ty with
-  | Arrow (ty0, ty1) ->
+  | TArrow (ty0, ty1) ->
       (* Sanity check *)
       assert (ty0 = arg.ty);
       let e = App (app, arg) in
@@ -340,7 +340,7 @@ let opt_destruct_function_call (e : texpression) :
 
 let opt_destruct_result (ty : ty) : ty option =
   match ty with
-  | Adt (Assumed Result, generics) ->
+  | TAdt (TAssumed TResult, generics) ->
       assert (generics.const_generics = []);
       assert (generics.trait_refs = []);
       Some (Collections.List.to_cons_nil generics.types)
@@ -350,14 +350,14 @@ let destruct_result (ty : ty) : ty = Option.get (opt_destruct_result ty)
 
 let opt_destruct_tuple (ty : ty) : ty list option =
   match ty with
-  | Adt (Tuple, generics) ->
+  | TAdt (TTuple, generics) ->
       assert (generics.const_generics = []);
       assert (generics.trait_refs = []);
       Some generics.types
   | _ -> None
 
 let mk_abs (x : typed_pattern) (e : texpression) : texpression =
-  let ty = Arrow (x.ty, e.ty) in
+  let ty = TArrow (x.ty, e.ty) in
   let e = Abs (x, e) in
   { e; ty }
 
@@ -370,12 +370,12 @@ let rec destruct_abs_list (e : texpression) : typed_pattern list * texpression =
 
 let destruct_arrow (ty : ty) : ty * ty =
   match ty with
-  | Arrow (ty0, ty1) -> (ty0, ty1)
+  | TArrow (ty0, ty1) -> (ty0, ty1)
   | _ -> raise (Failure "Not an arrow type")
 
 let rec destruct_arrows (ty : ty) : ty list * ty =
   match ty with
-  | Arrow (ty0, ty1) ->
+  | TArrow (ty0, ty1) ->
       let tys, out_ty = destruct_arrows ty1 in
       (ty0 :: tys, out_ty)
   | _ -> ([], ty)
@@ -408,7 +408,7 @@ let iter_switch_body_branches (f : texpression -> unit) (sb : switch_body) :
 let mk_switch (scrut : texpression) (sb : switch_body) : texpression =
   (* Sanity check: the scrutinee has the proper type *)
   (match sb with
-  | If (_, _) -> assert (scrut.ty = Literal Bool)
+  | If (_, _) -> assert (scrut.ty = TLiteral TBool)
   | Match branches ->
       List.iter
         (fun (b : match_branch) -> assert (b.pat.ty = scrut.ty))
@@ -427,13 +427,13 @@ let mk_switch (scrut : texpression) (sb : switch_body) : texpression =
 let mk_simpl_tuple_ty (tys : ty list) : ty =
   match tys with
   | [ ty ] -> ty
-  | _ -> Adt (Tuple, mk_generic_args_from_types tys)
+  | _ -> TAdt (TTuple, mk_generic_args_from_types tys)
 
-let mk_bool_ty : ty = Literal Bool
-let mk_unit_ty : ty = Adt (Tuple, empty_generic_args)
+let mk_bool_ty : ty = TLiteral TBool
+let mk_unit_ty : ty = TAdt (TTuple, empty_generic_args)
 
 let mk_unit_rvalue : texpression =
-  let id = AdtCons { adt_id = Tuple; variant_id = None } in
+  let id = AdtCons { adt_id = TTuple; variant_id = None } in
   let qualif = { id; generics = empty_generic_args } in
   let e = Qualif qualif in
   let ty = mk_unit_ty in
@@ -453,13 +453,13 @@ let mk_dummy_pattern (ty : ty) : typed_pattern =
   let value = PatDummy in
   { value; ty }
 
-let mk_meta (m : meta) (e : texpression) : texpression =
+let mk_emeta (m : emeta) (e : texpression) : texpression =
   let ty = e.ty in
   let e = Meta (m, e) in
   { e; ty }
 
 let mk_mplace_texpression (mp : mplace) (e : texpression) : texpression =
-  mk_meta (MPlace mp) e
+  mk_emeta (MPlace mp) e
 
 let mk_opt_mplace_texpression (mp : mplace option) (e : texpression) :
     texpression =
@@ -474,7 +474,7 @@ let mk_simpl_tuple_pattern (vl : typed_pattern list) : typed_pattern =
   | [ v ] -> v
   | _ ->
       let tys = List.map (fun (v : typed_pattern) -> v.ty) vl in
-      let ty = Adt (Tuple, mk_generic_args_from_types tys) in
+      let ty = TAdt (TTuple, mk_generic_args_from_types tys) in
       let value = PatAdt { variant_id = None; field_values = vl } in
       { value; ty }
 
@@ -485,10 +485,10 @@ let mk_simpl_tuple_texpression (vl : texpression list) : texpression =
   | _ ->
       (* Compute the types of the fields, and the type of the tuple constructor *)
       let tys = List.map (fun (v : texpression) -> v.ty) vl in
-      let ty = Adt (Tuple, mk_generic_args_from_types tys) in
+      let ty = TAdt (TTuple, mk_generic_args_from_types tys) in
       let ty = mk_arrows tys ty in
       (* Construct the tuple constructor qualifier *)
-      let id = AdtCons { adt_id = Tuple; variant_id = None } in
+      let id = AdtCons { adt_id = TTuple; variant_id = None } in
       let qualif = { id; generics = mk_generic_args_from_types tys } in
       (* Put everything together *)
       let cons = { e = Qualif qualif; ty } in
@@ -501,40 +501,40 @@ let mk_adt_pattern (adt_ty : ty) (variant_id : VariantId.id option)
 
 let ty_as_integer (t : ty) : T.integer_type =
   match t with
-  | Literal (Integer int_ty) -> int_ty
+  | TLiteral (TInteger int_ty) -> int_ty
   | _ -> raise (Failure "Unreachable")
 
 let ty_as_literal (t : ty) : T.literal_type =
-  match t with Literal ty -> ty | _ -> raise (Failure "Unreachable")
+  match t with TLiteral ty -> ty | _ -> raise (Failure "Unreachable")
 
-let mk_state_ty : ty = Adt (Assumed State, empty_generic_args)
+let mk_state_ty : ty = TAdt (TAssumed TState, empty_generic_args)
 
 let mk_result_ty (ty : ty) : ty =
-  Adt (Assumed Result, mk_generic_args_from_types [ ty ])
+  TAdt (TAssumed TResult, mk_generic_args_from_types [ ty ])
 
-let mk_error_ty : ty = Adt (Assumed Error, empty_generic_args)
-let mk_fuel_ty : ty = Adt (Assumed Fuel, empty_generic_args)
+let mk_error_ty : ty = TAdt (TAssumed TError, empty_generic_args)
+let mk_fuel_ty : ty = TAdt (TAssumed TFuel, empty_generic_args)
 
 let mk_error (error : VariantId.id) : texpression =
   let ty = mk_error_ty in
-  let id = AdtCons { adt_id = Assumed Error; variant_id = Some error } in
+  let id = AdtCons { adt_id = TAssumed TError; variant_id = Some error } in
   let qualif = { id; generics = empty_generic_args } in
   let e = Qualif qualif in
   { e; ty }
 
 let unwrap_result_ty (ty : ty) : ty =
   match ty with
-  | Adt
-      (Assumed Result, { types = [ ty ]; const_generics = []; trait_refs = [] })
-    ->
+  | TAdt
+      ( TAssumed TResult,
+        { types = [ ty ]; const_generics = []; trait_refs = [] } ) ->
       ty
   | _ -> raise (Failure "not a result type")
 
 let mk_result_fail_texpression (error : texpression) (ty : ty) : texpression =
   let type_args = [ ty ] in
-  let ty = Adt (Assumed Result, mk_generic_args_from_types type_args) in
+  let ty = TAdt (TAssumed TResult, mk_generic_args_from_types type_args) in
   let id =
-    AdtCons { adt_id = Assumed Result; variant_id = Some result_fail_id }
+    AdtCons { adt_id = TAssumed TResult; variant_id = Some result_fail_id }
   in
   let qualif = { id; generics = mk_generic_args_from_types type_args } in
   let cons_e = Qualif qualif in
@@ -549,9 +549,9 @@ let mk_result_fail_texpression_with_error_id (error : VariantId.id) (ty : ty) :
 
 let mk_result_return_texpression (v : texpression) : texpression =
   let type_args = [ v.ty ] in
-  let ty = Adt (Assumed Result, mk_generic_args_from_types type_args) in
+  let ty = TAdt (TAssumed TResult, mk_generic_args_from_types type_args) in
   let id =
-    AdtCons { adt_id = Assumed Result; variant_id = Some result_return_id }
+    AdtCons { adt_id = TAssumed TResult; variant_id = Some result_return_id }
   in
   let qualif = { id; generics = mk_generic_args_from_types type_args } in
   let cons_e = Qualif qualif in
@@ -562,7 +562,7 @@ let mk_result_return_texpression (v : texpression) : texpression =
 (** Create a [Fail err] pattern which captures the error *)
 let mk_result_fail_pattern (error_pat : pattern) (ty : ty) : typed_pattern =
   let error_pat : typed_pattern = { value = error_pat; ty = mk_error_ty } in
-  let ty = Adt (Assumed Result, mk_generic_args_from_types [ ty ]) in
+  let ty = TAdt (TAssumed TResult, mk_generic_args_from_types [ ty ]) in
   let value =
     PatAdt { variant_id = Some result_fail_id; field_values = [ error_pat ] }
   in
@@ -574,7 +574,7 @@ let mk_result_fail_pattern_ignore_error (ty : ty) : typed_pattern =
   mk_result_fail_pattern error_pat ty
 
 let mk_result_return_pattern (v : typed_pattern) : typed_pattern =
-  let ty = Adt (Assumed Result, mk_generic_args_from_types [ v.ty ]) in
+  let ty = TAdt (TAssumed TResult, mk_generic_args_from_types [ v.ty ]) in
   let value =
     PatAdt { variant_id = Some result_return_id; field_values = [ v ] }
   in
@@ -646,10 +646,15 @@ let trait_decl_get_method (trait_decl : trait_decl) (method_name : string) :
 let trait_decl_is_empty (trait_decl : trait_decl) : bool =
   let {
     def_id = _;
+    is_local = _;
     name = _;
+    llbc_name = _;
+    meta = _;
     generics = _;
+    llbc_generics = _;
     preds = _;
     parent_clauses;
+    llbc_parent_clauses = _;
     consts;
     types;
     required_methods;
@@ -663,9 +668,14 @@ let trait_decl_is_empty (trait_decl : trait_decl) : bool =
 let trait_impl_is_empty (trait_impl : trait_impl) : bool =
   let {
     def_id = _;
+    is_local = _;
     name = _;
+    llbc_name = _;
+    meta = _;
     impl_trait = _;
+    llbc_impl_trait = _;
     generics = _;
+    llbc_generics = _;
     preds = _;
     parent_trait_refs;
     consts;
diff --git a/compiler/RegionsHierarchy.ml b/compiler/RegionsHierarchy.ml
new file mode 100644
index 00000000..e101ba49
--- /dev/null
+++ b/compiler/RegionsHierarchy.ml
@@ -0,0 +1,297 @@
+(** This module analyzes function signatures to compute the
+    hierarchy between regions.
+
+    Note that we don't need to analyze the types: when there is a non-trivial
+    relation between lifetimes in a type definition, the Rust compiler will
+    automatically introduce the relevant where clauses. For instance, in the
+    definition below:
+
+    {[
+      struct Wrapper<'a, 'b, T> {
+        x : &'a mut &'b mut T,
+      }
+    ]}
+    
+    the Rust compiler will introduce the where clauses:
+    {[
+      'b : 'a
+      T : 'b
+    ]}
+
+    However, it doesn't do so for the function signatures, which means we have
+    to compute the constraints between the lifetimes ourselves, then that we
+    have to compute the SCCs of the lifetimes (two lifetimes 'a and 'b may
+    satisfy 'a : 'b and 'b : 'a, meaning they are actually equal and should
+    be grouped together).
+ *)
+
+open Types
+open TypesUtils
+open Expressions
+open LlbcAst
+open LlbcAstUtils
+open Assumed
+open SCC
+module Subst = Substitute
+
+(** The local logger *)
+let log = Logging.regions_hierarchy_log
+
+let compute_regions_hierarchy_for_sig (type_decls : type_decl TypeDeclId.Map.t)
+    (fun_decls : fun_decl FunDeclId.Map.t)
+    (global_decls : global_decl GlobalDeclId.Map.t)
+    (trait_decls : trait_decl TraitDeclId.Map.t)
+    (trait_impls : trait_impl TraitImplId.Map.t) (fun_name : string)
+    (sg : fun_sig) : region_groups =
+  log#ldebug (lazy (__FUNCTION__ ^ ": " ^ fun_name));
+  (* Initialize a normalization context (we may need to normalize some
+     associated types) *)
+  let norm_ctx : AssociatedTypes.norm_ctx =
+    let norm_trait_types =
+      AssociatedTypes.compute_norm_trait_types_from_preds
+        sg.preds.trait_type_constraints
+    in
+    {
+      norm_trait_types;
+      type_decls;
+      fun_decls;
+      global_decls;
+      trait_decls;
+      trait_impls;
+      type_vars = sg.generics.types;
+      const_generic_vars = sg.generics.const_generics;
+    }
+  in
+
+  (* Create the dependency graph.
+
+     An edge from 'short to 'long means that 'long outlives 'short (that is
+     we have 'long : 'short,  using Rust notations).
+  *)
+  (* First initialize the regions map.
+
+     We add:
+     - the region variables
+     - the static region
+     - edges from the region variables to the static region
+  *)
+  let g : RegionSet.t RegionMap.t ref =
+    let s_set = RegionSet.singleton RStatic in
+    let m =
+      List.map
+        (fun (r : region_var) -> (RVar r.index, s_set))
+        sg.generics.regions
+    in
+    let s = (RStatic, RegionSet.empty) in
+    ref (RegionMap.of_list (s :: m))
+  in
+
+  let add_edge ~(short : region) ~(long : region) =
+    let m = !g in
+    let s = RegionMap.find short !g in
+    let s = RegionSet.add long s in
+    g := RegionMap.add short s m
+  in
+
+  let add_edge_from_region_constraint ((long, short) : region_outlives) =
+    add_edge ~short ~long
+  in
+
+  let add_edges ~(long : region) ~(shorts : region list) =
+    List.iter (fun short -> add_edge ~short ~long) shorts
+  in
+
+  (* Explore the clauses - we only explore the "region outlives" clause,
+     not the "type outlives" clauses *)
+  List.iter add_edge_from_region_constraint sg.preds.regions_outlive;
+
+  (* Explore the types in the signature to add the edges *)
+  let rec explore_ty (outer : region list) (ty : ty) =
+    match ty with
+    | TAdt (id, generics) ->
+        (* Add constraints coming from the type clauses *)
+        (match id with
+        | TAdtId id ->
+            (* Lookup the type declaration *)
+            let decl = TypeDeclId.Map.find id type_decls in
+            (* Instantiate the predicates *)
+            let tr_self =
+              UnknownTrait ("Unexpected, introduced by " ^ __FUNCTION__)
+            in
+            let subst =
+              Subst.make_subst_from_generics decl.generics generics tr_self
+            in
+            let predicates = Subst.predicates_substitute subst decl.preds in
+            (* Note that because we also explore the generics below, we may
+               explore several times the same type - this is ok *)
+            List.iter
+              (fun (long, short) -> add_edges ~long ~shorts:(short :: outer))
+              predicates.regions_outlive;
+            List.iter
+              (fun (ty, short) -> explore_ty (short :: outer) ty)
+              predicates.types_outlive
+        | TTuple -> (* No clauses for tuples *) ()
+        | TAssumed aid -> (
+            match aid with
+            | TBox | TArray | TSlice | TStr -> (* No clauses for those *) ()));
+        (* Explore the generics *)
+        explore_generics outer generics
+    | TVar _ | TLiteral _ | TNever -> ()
+    | TRef (r, ty, _) ->
+        (* Add the constraints for r *)
+        add_edges ~long:r ~shorts:outer;
+        (* Add r to the outer regions *)
+        let outer = r :: outer in
+        (* Continue *)
+        explore_ty outer ty
+    | TRawPtr (ty, _) -> explore_ty outer ty
+    | TTraitType (trait_ref, _generic_args, _) ->
+        (* The trait should reference a clause, and not an implementation
+           (otherwise it should have been normalized) *)
+        assert (
+          AssociatedTypes.trait_instance_id_is_local_clause trait_ref.trait_id);
+        (* We have nothing to do *)
+        ()
+    | TArrow (inputs, output) ->
+        (* TODO: this may be too constraining *)
+        List.iter (explore_ty outer) (output :: inputs)
+  and explore_generics (outer : region list) (generics : generic_args) =
+    let { regions; types; const_generics = _; trait_refs = _ } = generics in
+    List.iter (fun long -> add_edges ~long ~shorts:outer) regions;
+    List.iter (explore_ty outer) types
+  in
+
+  (* Normalize the types then explore *)
+  let tys =
+    List.map
+      (AssociatedTypes.norm_ctx_normalize_ty norm_ctx)
+      (sg.output :: sg.inputs)
+  in
+  List.iter (explore_ty []) tys;
+
+  (* Compute the ordered SCCs *)
+  let module Scc = SCC.Make (RegionOrderedType) in
+  let sccs = Scc.compute (RegionMap.bindings !g) in
+
+  (* Remove the SCC containing the static region.
+
+     For now, we don't handle cases where regions different from 'static
+     can live as long as 'static, so we check that if the group contains
+     'static then it is the only region it contains, and then we filter
+     the group.
+     TODO: general support for 'static
+  *)
+  let sccs =
+    (* Find the SCC which contains the static region *)
+    let static_gr_id, static_scc =
+      List.find
+        (fun (_, scc) -> List.mem RStatic scc)
+        (SccId.Map.bindings sccs.sccs)
+    in
+    (* The SCC should only contain the 'static *)
+    assert (static_scc = [ RStatic ]);
+    (* Remove the group as well as references to this group from the
+       other SCCs *)
+    let { sccs; scc_deps } = sccs in
+    (* We have to change the indexing:
+       - if id < static_gr_id: we leave the id as it is
+       - if id = static_gr_id: we remove id
+       - if id > static_gr_id: we decrement it by one
+    *)
+    let static_i = SccId.to_int static_gr_id in
+    let convert_id (id : SccId.id) : SccId.id option =
+      let i = SccId.to_int id in
+      if i < static_i then Some id
+      else if i = static_i then None
+      else Some (SccId.of_int (i - 1))
+    in
+    let sccs =
+      SccId.Map.of_list
+        (List.filter_map
+           (fun (id, rg_ids) ->
+             match convert_id id with
+             | None -> None
+             | Some id -> Some (id, rg_ids))
+           (SccId.Map.bindings sccs))
+    in
+
+    let scc_deps =
+      List.filter_map
+        (fun (id, deps) ->
+          match convert_id id with
+          | None -> None
+          | Some id ->
+              let deps = List.filter_map convert_id (SccId.Set.elements deps) in
+              Some (id, SccId.Set.of_list deps))
+        (SccId.Map.bindings scc_deps)
+    in
+    let scc_deps = SccId.Map.of_list scc_deps in
+
+    { sccs; scc_deps }
+  in
+
+  (*
+   * Compute the regions hierarchy
+   *)
+  List.filter_map
+    (fun (scc_id, scc) ->
+      (* The region id *)
+      let i = SccId.to_int scc_id in
+      let id = RegionGroupId.of_int i in
+
+      (* Retrieve the set of regions in the group *)
+      let regions =
+        List.map
+          (fun r ->
+            match r with RVar r -> r | _ -> raise (Failure "Unreachable"))
+          scc
+      in
+
+      (* Compute the set of parent region groups *)
+      let parents =
+        List.map
+          (fun id -> RegionGroupId.of_int (SccId.to_int id))
+          (SccId.Set.elements (SccId.Map.find scc_id sccs.scc_deps))
+      in
+
+      (* Put together *)
+      Some { id; regions; parents })
+    (SccId.Map.bindings sccs.sccs)
+
+let compute_regions_hierarchies (type_decls : type_decl TypeDeclId.Map.t)
+    (fun_decls : fun_decl FunDeclId.Map.t)
+    (global_decls : global_decl GlobalDeclId.Map.t)
+    (trait_decls : trait_decl TraitDeclId.Map.t)
+    (trait_impls : trait_impl TraitImplId.Map.t) : region_groups FunIdMap.t =
+  let open Print in
+  let env : fmt_env =
+    {
+      type_decls;
+      fun_decls;
+      global_decls;
+      trait_decls;
+      trait_impls;
+      generics = empty_generic_params;
+      preds = empty_predicates;
+      locals = [];
+    }
+  in
+  let regular =
+    List.map
+      (fun ((fid, d) : FunDeclId.id * fun_decl) ->
+        (FRegular fid, (Types.name_to_string env d.name, d.signature)))
+      (FunDeclId.Map.bindings fun_decls)
+  in
+  let assumed =
+    List.map
+      (fun (info : assumed_fun_info) ->
+        (FAssumed info.fun_id, (info.name, info.fun_sig)))
+      assumed_fun_infos
+  in
+  FunIdMap.of_list
+    (List.map
+       (fun (fid, (name, sg)) ->
+         ( fid,
+           compute_regions_hierarchy_for_sig type_decls fun_decls global_decls
+             trait_decls trait_impls name sg ))
+       (regular @ assumed))
diff --git a/compiler/ReorderDecls.ml b/compiler/ReorderDecls.ml
index 10b68da3..53c94ff4 100644
--- a/compiler/ReorderDecls.ml
+++ b/compiler/ReorderDecls.ml
@@ -1,4 +1,3 @@
-open Graph
 open Collections
 open SCC
 open Pure
@@ -46,8 +45,8 @@ let compute_body_fun_deps (e : texpression) : FunIdSet.t =
             | Pure _ -> ()
             | FromLlbc (fid, lp_id, rg_id) -> (
                 match fid with
-                | FunId (Assumed _) -> ()
-                | TraitMethod (_, _, fid) | FunId (Regular fid) ->
+                | FunId (FAssumed _) -> ()
+                | TraitMethod (_, _, fid) | FunId (FRegular fid) ->
                     let id = { def_id = fid; lp_id; rg_id } in
                     ids := FunIdSet.add id !ids))
     end
@@ -99,99 +98,9 @@ let group_reorder_fun_decls (decls : fun_decl list) :
       decls
   in
 
-  (*
-   * Create the dependency graph
-   *)
-  (* Convert the ids to vertices (i.e., injectively map ids to integers, and create
-     vertices labeled with those integers).
-
-     Rem.: [Graph.create] is *imperative*: it generates a new vertex every time
-     it is called (!!).
-  *)
-  let module Graph = Pack.Digraph in
-  let id_to_vertex : Graph.V.t FunIdMap.t =
-    let cnt = ref 0 in
-    FunIdMap.of_list
-      (List.map
-         (fun id ->
-           let lbl = !cnt in
-           cnt := !cnt + 1;
-           (* We create a vertex *)
-           let v = Graph.V.create lbl in
-           (id, v))
-         idl)
-  in
-  let vertex_to_id : fun_id IntMap.t =
-    IntMap.of_list
-      (List.map
-         (fun (fid, v) -> (Graph.V.label v, fid))
-         (FunIdMap.bindings id_to_vertex))
-  in
-
-  let to_v id = FunIdMap.find id id_to_vertex in
-  let to_id v = IntMap.find (Graph.V.label v) vertex_to_id in
-
-  let g = Graph.create () in
-
-  (* Add the edges, first from the vertices to themselves, then between vertices *)
-  List.iter
-    (fun (fun_id, deps) ->
-      let v = to_v fun_id in
-      Graph.add_edge g v v;
-      FunIdSet.iter (fun dep_id -> Graph.add_edge g v (to_v dep_id)) deps)
-    deps;
-
-  (* Compute the SCCs *)
-  let module Comp = Components.Make (Graph) in
-  let sccs = Comp.scc_list g in
-
-  (* Convert the vertices to ids *)
-  let sccs = List.map (List.map to_id) sccs in
-
-  log#ldebug
-    (lazy
-      ("group_reorder_fun_decls: SCCs:\n"
-      ^ Print.list_to_string (Print.list_to_string FunIdOrderedType.show_t) sccs
-      ));
-
-  (* Sanity check *)
-  let _ =
-    (* Check that the SCCs are pairwise disjoint *)
-    assert (FunIdSet.pairwise_disjoint (List.map FunIdSet.of_list sccs));
-    (* Check that all the ids are in the sccs *)
-    let scc_ids = FunIdSet.of_list (List.concat sccs) in
-
-    log#ldebug
-      (lazy
-        ("group_reorder_fun_decls: sanity check:" ^ "\n- ids    : "
-       ^ FunIdSet.show ids ^ "\n- scc_ids: " ^ FunIdSet.show scc_ids));
-
-    assert (FunIdSet.equal scc_ids ids)
-  in
-
-  log#ldebug
-    (lazy
-      ("group_reorder_fun_decls: reordered SCCs:\n"
-      ^ Print.list_to_string (Print.list_to_string FunIdOrderedType.show_t) sccs
-      ));
-
-  (* Reorder *)
-  let module Reorder = SCC.Make (FunIdOrderedType) in
-  let id_deps =
-    FunIdMap.of_list
-      (List.map (fun (fid, deps) -> (fid, FunIdSet.elements deps)) deps)
-  in
-  let sccs = Reorder.reorder_sccs id_deps idl sccs in
-
-  (* Sanity check *)
-  let _ =
-    (* Check that the SCCs are pairwise disjoint *)
-    let sccs = List.map snd (SccId.Map.bindings sccs.sccs) in
-    assert (FunIdSet.pairwise_disjoint (List.map FunIdSet.of_list sccs));
-    (* Check that all the ids are in the sccs *)
-    let scc_ids = FunIdSet.of_list (List.concat sccs) in
-    assert (FunIdSet.equal scc_ids ids)
-  in
+  (* Compute the ordered SCCs *)
+  let module Scc = SCC.Make (FunIdOrderedType) in
+  let sccs = Scc.compute deps in
 
   (* Group the declarations *)
   let deps = FunIdMap.of_list deps in
diff --git a/compiler/SCC.ml b/compiler/SCC.ml
index d9a4cd3e..150821ad 100644
--- a/compiler/SCC.ml
+++ b/compiler/SCC.ml
@@ -6,8 +6,15 @@ module SccId = Identifiers.IdGen ()
 (** The local logger *)
 let log = Logging.scc_log
 
+(** A structure containing information about SCCs (strongly connected components) *)
+type 'id sccs = {
+  sccs : 'id list SccId.Map.t;
+  scc_deps : SccId.Set.t SccId.Map.t;  (** The dependencies between sccs *)
+}
+[@@deriving show]
+
 (** A functor which provides functions to work on strongly connected components *)
-module Make (Id : OrderedType) = struct
+module MakeReorder (Id : OrderedType) = struct
   module IdMap = MakeMap (Id)
   module IdSet = MakeSet (Id)
 
@@ -15,13 +22,6 @@ module Make (Id : OrderedType) = struct
 
   let pp_id = Id.pp_t
 
-  (** A structure containing information about SCCs (strongly connected components) *)
-  type sccs = {
-    sccs : id list SccId.Map.t;
-    scc_deps : SccId.Set.t SccId.Map.t;  (** The dependencies between sccs *)
-  }
-  [@@deriving show]
-
   (** The order in which Tarjan's algorithm generates the SCCs is arbitrary,
       while we want to keep as much as possible the original order (the order
       in which the user generated the ids). For this, we iterate through
@@ -93,7 +93,7 @@ module Make (Id : OrderedType) = struct
       Charon project.
   *)
   let reorder_sccs (id_deps : Id.t list IdMap.t) (ids : Id.t list)
-      (sccs : Id.t list list) : sccs =
+      (sccs : Id.t list list) : id sccs =
     (* Map the identifiers to the SCC indices *)
     let id_to_scc =
       IdMap.of_list
@@ -168,13 +168,114 @@ module Make (Id : OrderedType) = struct
     { sccs = tgt_sccs; scc_deps = tgt_deps }
 end
 
+module Make (Id : OrderedType) = struct
+  module M = MakeMap (Id)
+  module S = MakeSet (Id)
+
+  (** Compute the ordered SCC components for a graph, which is a map
+      from identifier to set of identifiers (which represent the set
+      of edges starting from an identifier).
+   *)
+  let compute (m : (Id.t * S.t) list) : Id.t sccs =
+    (*
+     * Create the dependency graph
+     *)
+    (* Compute the list/set of identifiers *)
+    let idl = List.map fst m in
+    let ids = S.of_list idl in
+
+    (* Convert the ids to vertices (i.e., injectively map ids to integers,
+       and create vertices labeled with those integers).
+
+       Rem.: [Graph.create] is *imperative*: it generates a new vertex every
+       time it is called (!!). For this reason, we first add all the vertices
+       we need, then add the edges.
+    *)
+    let open Graph in
+    let module IntMap = MakeMap (OrderedInt) in
+    let module Graph = Pack.Digraph in
+    let id_to_vertex : Graph.V.t M.t =
+      let cnt = ref 0 in
+      M.of_list
+        (List.map
+           (fun id ->
+             let lbl = !cnt in
+             cnt := !cnt + 1;
+             (* We create a vertex *)
+             let v = Graph.V.create lbl in
+             (id, v))
+           idl)
+    in
+    let vertex_to_id : Id.t IntMap.t =
+      IntMap.of_list
+        (List.map
+           (fun (fid, v) -> (Graph.V.label v, fid))
+           (M.bindings id_to_vertex))
+    in
+
+    let to_v id = M.find id id_to_vertex in
+    let to_id v = IntMap.find (Graph.V.label v) vertex_to_id in
+
+    let g = Graph.create () in
+
+    (* Add the edges, first from the vertices to themselves, then between
+       vertices. *)
+    List.iter
+      (fun (id, deps) ->
+        let v = to_v id in
+        Graph.add_edge g v v;
+        S.iter (fun dep_id -> Graph.add_edge g v (to_v dep_id)) deps)
+      m;
+
+    (* Compute the SCCs *)
+    let module Comp = Components.Make (Graph) in
+    let sccs = Comp.scc_list g in
+
+    (* Convert the vertices to ids *)
+    let sccs = List.map (List.map to_id) sccs in
+
+    (* Sanity check *)
+    let _ =
+      (* Check that the SCCs are pairwise disjoint *)
+      assert (S.pairwise_disjoint (List.map S.of_list sccs));
+      (* Check that all the ids are in the sccs *)
+      let scc_ids = S.of_list (List.concat sccs) in
+
+      log#ldebug
+        (lazy
+          ("group_reorder_fun_decls: sanity check:" ^ "\n- ids    : "
+         ^ S.show ids ^ "\n- scc_ids: " ^ S.show scc_ids));
+
+      assert (S.equal scc_ids ids)
+    in
+
+    (* Reorder *)
+    let module Reorder = MakeReorder (Id) in
+    let id_deps =
+      M.of_list (List.map (fun (fid, deps) -> (fid, S.elements deps)) m)
+    in
+    let sccs = Reorder.reorder_sccs id_deps idl sccs in
+
+    (* Sanity check *)
+    let _ =
+      (* Check that the SCCs are pairwise disjoint *)
+      let sccs = List.map snd (SccId.Map.bindings sccs.sccs) in
+      assert (S.pairwise_disjoint (List.map S.of_list sccs));
+      (* Check that all the ids are in the sccs *)
+      let scc_ids = S.of_list (List.concat sccs) in
+      assert (S.equal scc_ids ids)
+    in
+
+    sccs
+end
+
 (** Test - TODO: make "real" unit tests *)
 let _ =
   (* Check that some SCCs are correctly reordered *)
   let check_sccs (id_deps : (int * int list) list) (ids : int list)
       (sccs : int list list) (tgt_sccs : int list list) : unit =
     let module Ord = OrderedInt in
-    let module Reorder = Make (Ord) in
+    let module Reorder = MakeReorder (Ord) in
     let module Map = MakeMap (Ord) in
     let id_deps = Map.of_list id_deps in
 
diff --git a/compiler/StringUtils.ml b/compiler/StringUtils.ml
index 161df27b..3ab4e808 100644
--- a/compiler/StringUtils.ml
+++ b/compiler/StringUtils.ml
@@ -1,111 +1 @@
-(** Utilities to work on strings, character per character.
-
-    They operate on ASCII strings, and are used by the project to convert
-    Rust names: Rust names are not fancy, so it shouldn't be a problem.
-    
-    Rk.: the poor support of OCaml for char manipulation is really annoying...
- *)
-
-let code_0 = 48
-let code_9 = 57
-let code_A = 65
-let code_Z = 90
-let code_a = 97
-let code_z = 122
-
-let is_lowercase_ascii (c : char) : bool =
-  let c = Char.code c in
-  code_a <= c && c <= code_z
-
-let is_uppercase_ascii (c : char) : bool =
-  let c = Char.code c in
-  code_A <= c && c <= code_Z
-
-let is_letter_ascii (c : char) : bool =
-  is_lowercase_ascii c || is_uppercase_ascii c
-
-let is_digit_ascii (c : char) : bool =
-  let c = Char.code c in
-  code_0 <= c && c <= code_9
-
-let lowercase_ascii = Char.lowercase_ascii
-let uppercase_ascii = Char.uppercase_ascii
-
-(** Using buffers as per:
-    {{: https://stackoverflow.com/questions/29957418/how-to-convert-char-list-to-string-in-ocaml} stackoverflow}
- *)
-let string_of_chars (chars : char list) : string =
-  let buf = Buffer.create (List.length chars) in
-  List.iter (Buffer.add_char buf) chars;
-  Buffer.contents buf
-
-let string_to_chars (s : string) : char list =
-  let length = String.length s in
-  let rec apply i =
-    if i = length then [] else String.get s i :: apply (i + 1)
-  in
-  apply 0
-
-(** This operates on ASCII *)
-let to_camel_case (s : string) : string =
-  (* Note that we rebuild the string in reverse order *)
-  let apply ((prev_is_under, acc) : bool * char list) (c : char) :
-      bool * char list =
-    if c = '_' then (true, acc)
-    else
-      let c = if prev_is_under then uppercase_ascii c else c in
-      (false, c :: acc)
-  in
-  let _, chars = List.fold_left apply (true, []) (string_to_chars s) in
-  string_of_chars (List.rev chars)
-
-(** This operates on ASCII *)
-let to_snake_case (s : string) : string =
-  (* Note that we rebuild the string in reverse order *)
-  let apply ((prev_is_low, prev_is_digit, acc) : bool * bool * char list)
-      (c : char) : bool * bool * char list =
-    let acc =
-      if c = '_' then acc
-      else if prev_is_digit then if is_letter_ascii c then '_' :: acc else acc
-      else if prev_is_low then
-        if (is_lowercase_ascii c || is_digit_ascii c) && c <> '_' then acc
-        else '_' :: acc
-      else acc
-    in
-    let prev_is_low = is_lowercase_ascii c in
-    let prev_is_digit = is_digit_ascii c in
-    let c = lowercase_ascii c in
-    (prev_is_low, prev_is_digit, c :: acc)
-  in
-  let _, _, chars =
-    List.fold_left apply (false, false, []) (string_to_chars s)
-  in
-  string_of_chars (List.rev chars)
-
-(** Applies a map operation.
-
-    This is very inefficient, but shouldn't be used much.
- *)
-let map (f : char -> string) (s : string) : string =
-  let sl = List.map f (string_to_chars s) in
-  let sl = List.map string_to_chars sl in
-  string_of_chars (List.concat sl)
-
-let capitalize_first_letter (s : string) : string =
-  let s = string_to_chars s in
-  let s = match s with [] -> s | c :: s' -> uppercase_ascii c :: s' in
-  string_of_chars s
-
-let lowercase_first_letter (s : string) : string =
-  let s = string_to_chars s in
-  let s = match s with [] -> s | c :: s' -> lowercase_ascii c :: s' in
-  string_of_chars s
-
-(** Unit tests *)
-let _ =
-  assert (to_camel_case "hello_world" = "HelloWorld");
-  assert (to_snake_case "HelloWorld36Hello" = "hello_world36_hello");
-  assert (to_snake_case "HELLO" = "hello");
-  assert (to_snake_case "T1" = "t1");
-  assert (to_camel_case "list" = "List");
-  assert (to_snake_case "is_cons" = "is_cons")
+include Charon.StringUtils
diff --git a/compiler/Substitute.ml b/compiler/Substitute.ml
index 23f618e2..73e7f71d 100644
--- a/compiler/Substitute.ml
+++ b/compiler/Substitute.ml
@@ -2,34 +2,34 @@
     function bodies, etc.
  *)
 
-module T = Types
-module TU = TypesUtils
-module V = Values
-module E = Expressions
-module A = LlbcAst
-module C = Contexts
-
-type ('r1, 'r2) subst = {
-  r_subst : 'r1 -> 'r2;
-  ty_subst : T.TypeVarId.id -> 'r2 T.ty;
-  cg_subst : T.ConstGenericVarId.id -> T.const_generic;
+open Types
+open TypesUtils
+open Values
+open Expressions
+open LlbcAst
+open Contexts
+
+type subst = {
+  r_subst : region -> region;
+  ty_subst : TypeVarId.id -> ty;
+  cg_subst : ConstGenericVarId.id -> const_generic;
       (** Substitution from *local* trait clause to trait instance *)
-  tr_subst : T.TraitClauseId.id -> 'r2 T.trait_instance_id;
+  tr_subst : TraitClauseId.id -> trait_instance_id;
       (** Substitution for the [Self] trait instance *)
-  tr_self : 'r2 T.trait_instance_id;
+  tr_self : trait_instance_id;
 }
 
-let ty_substitute_visitor (subst : ('r1, 'r2) subst) =
+let st_substitute_visitor (subst : subst) =
   object
-    inherit [_] T.map_ty
-    method visit_'r _ r = subst.r_subst r
-    method! visit_TypeVar _ id = subst.ty_subst id
+    inherit [_] map_statement
+    method! visit_region _ r = subst.r_subst r
+    method! visit_TVar _ id = subst.ty_subst id
 
     method! visit_type_var_id _ _ =
       (* We should never get here because we reimplemented [visit_TypeVar] *)
       raise (Failure "Unexpected")
 
-    method! visit_ConstGenericVar _ id = subst.cg_subst id
+    method! visit_CgVar _ id = subst.cg_subst id
 
     method! visit_const_generic_var_id _ _ =
       (* We should never get here because we reimplemented [visit_Var] *)
@@ -43,193 +43,175 @@ let ty_substitute_visitor (subst : ('r1, 'r2) subst) =
 
     **IMPORTANT**: this doesn't normalize the types.
  *)
-let ty_substitute (subst : ('r1, 'r2) subst) (ty : 'r1 T.ty) : 'r2 T.ty =
-  let visitor = ty_substitute_visitor subst in
+let ty_substitute (subst : subst) (ty : ty) : ty =
+  let visitor = st_substitute_visitor subst in
   visitor#visit_ty () ty
 
 (** **IMPORTANT**: this doesn't normalize the types. *)
-let trait_ref_substitute (subst : ('r1, 'r2) subst) (tr : 'r1 T.trait_ref) :
-    'r2 T.trait_ref =
-  let visitor = ty_substitute_visitor subst in
+let trait_ref_substitute (subst : subst) (tr : trait_ref) : trait_ref =
+  let visitor = st_substitute_visitor subst in
   visitor#visit_trait_ref () tr
 
 (** **IMPORTANT**: this doesn't normalize the types. *)
-let generic_args_substitute (subst : ('r1, 'r2) subst) (g : 'r1 T.generic_args)
-    : 'r2 T.generic_args =
-  let visitor = ty_substitute_visitor subst in
+let trait_instance_id_substitute (subst : subst) (tr : trait_instance_id) :
+    trait_instance_id =
+  let visitor = st_substitute_visitor subst in
+  visitor#visit_trait_instance_id () tr
+
+(** **IMPORTANT**: this doesn't normalize the types. *)
+let generic_args_substitute (subst : subst) (g : generic_args) : generic_args =
+  let visitor = st_substitute_visitor subst in
   visitor#visit_generic_args () g
 
-let erase_regions_subst : ('r, T.erased_region) subst =
+let predicates_substitute (subst : subst) (p : predicates) : predicates =
+  let visitor = st_substitute_visitor subst in
+  visitor#visit_predicates () p
+
+let erase_regions_subst : subst =
   {
-    r_subst = (fun _ -> T.Erased);
-    ty_subst = (fun vid -> T.TypeVar vid);
-    cg_subst = (fun id -> T.ConstGenericVar id);
-    tr_subst = (fun id -> T.Clause id);
-    tr_self = T.Self;
+    r_subst = (fun _ -> RErased);
+    ty_subst = (fun vid -> TVar vid);
+    cg_subst = (fun id -> CgVar id);
+    tr_subst = (fun id -> Clause id);
+    tr_self = Self;
   }
 
-(** Convert an {!T.rty} to an {!T.ety} by erasing the region variables *)
-let erase_regions (ty : 'r T.ty) : T.ety = ty_substitute erase_regions_subst ty
+(** Convert an {!rty} to an {!ety} by erasing the region variables *)
+let erase_regions (ty : ty) : ty = ty_substitute erase_regions_subst ty
 
-let trait_ref_erase_regions (tr : 'r T.trait_ref) : T.etrait_ref =
+let trait_ref_erase_regions (tr : trait_ref) : trait_ref =
   trait_ref_substitute erase_regions_subst tr
 
+let trait_instance_id_erase_regions (tr : trait_instance_id) : trait_instance_id
+    =
+  trait_instance_id_substitute erase_regions_subst tr
+
+let generic_args_erase_regions (tr : generic_args) : generic_args =
+  generic_args_substitute erase_regions_subst tr
+
 (** Generate fresh regions for region variables.
 
     Return the list of new regions and appropriate substitutions from the
     original region variables to the fresh regions.
     
-    TODO: simplify? we only need the subst [T.RegionVarId.id -> T.RegionId.id]
+    TODO: simplify? we only need the subst [RegionVarId.id -> RegionId.id]
   *)
-let fresh_regions_with_substs (region_vars : T.region_var list) :
-    T.RegionId.id list
-    * (T.RegionVarId.id -> T.RegionId.id)
-    * (T.RegionVarId.id T.region -> T.RegionId.id T.region) =
+let fresh_regions_with_substs (region_vars : region_var list) :
+    RegionId.id list * (RegionId.id -> RegionId.id) * (region -> region) =
   (* Generate fresh regions *)
-  let fresh_region_ids = List.map (fun _ -> C.fresh_region_id ()) region_vars in
+  let fresh_region_ids = List.map (fun _ -> fresh_region_id ()) region_vars in
   (* Generate the map from region var ids to regions *)
   let ls = List.combine region_vars fresh_region_ids in
   let rid_map =
     List.fold_left
-      (fun mp ((k : T.region_var), v) -> T.RegionVarId.Map.add k.T.index v mp)
-      T.RegionVarId.Map.empty ls
+      (fun mp ((k : region_var), v) -> RegionId.Map.add k.index v mp)
+      RegionId.Map.empty ls
   in
   (* Generate the substitution from region var id to region *)
-  let rid_subst id = T.RegionVarId.Map.find id rid_map in
+  let rid_subst id = RegionId.Map.find id rid_map in
   (* Generate the substitution from region to region *)
-  let r_subst r =
-    match r with T.Static -> T.Static | T.Var id -> T.Var (rid_subst id)
+  let r_subst (r : region) =
+    match r with RStatic | RErased -> r | RVar id -> RVar (rid_subst id)
   in
   (* Return *)
   (fresh_region_ids, rid_subst, r_subst)
 
 (** Erase the regions in a type and perform a substitution *)
-let erase_regions_substitute_types (ty_subst : T.TypeVarId.id -> T.ety)
-    (cg_subst : T.ConstGenericVarId.id -> T.const_generic)
-    (tr_subst : T.TraitClauseId.id -> T.etrait_instance_id)
-    (tr_self : T.etrait_instance_id) (ty : 'r T.ty) : T.ety =
-  let r_subst (_ : 'r) : T.erased_region = T.Erased in
+let erase_regions_substitute_types (ty_subst : TypeVarId.id -> ty)
+    (cg_subst : ConstGenericVarId.id -> const_generic)
+    (tr_subst : TraitClauseId.id -> trait_instance_id)
+    (tr_self : trait_instance_id) (ty : ty) : ty =
+  let r_subst (_ : region) : region = RErased in
   let subst = { r_subst; ty_subst; cg_subst; tr_subst; tr_self } in
   ty_substitute subst ty
 
 (** Create a region substitution from a list of region variable ids and a list of
     regions (with which to substitute the region variable ids *)
-let make_region_subst (var_ids : T.RegionVarId.id list)
-    (regions : 'r T.region list) : T.RegionVarId.id T.region -> 'r T.region =
+let make_region_subst (var_ids : RegionId.id list) (regions : region list) :
+    region -> region =
   let ls = List.combine var_ids regions in
   let mp =
     List.fold_left
-      (fun mp (k, v) -> T.RegionVarId.Map.add k v mp)
-      T.RegionVarId.Map.empty ls
+      (fun mp (k, v) -> RegionId.Map.add k v mp)
+      RegionId.Map.empty ls
   in
   fun r ->
-    match r with
-    | T.Static -> T.Static
-    | T.Var id -> T.RegionVarId.Map.find id mp
+    match r with RStatic | RErased -> r | RVar id -> RegionId.Map.find id mp
 
-let make_region_subst_from_vars (vars : T.region_var list)
-    (regions : 'r T.region list) : T.RegionVarId.id T.region -> 'r T.region =
-  make_region_subst
-    (List.map (fun (x : T.region_var) -> x.T.index) vars)
-    regions
+let make_region_subst_from_vars (vars : region_var list) (regions : region list)
+    : region -> region =
+  make_region_subst (List.map (fun (x : region_var) -> x.index) vars) regions
 
 (** Create a type substitution from a list of type variable ids and a list of
     types (with which to substitute the type variable ids) *)
-let make_type_subst (var_ids : T.TypeVarId.id list) (tys : 'r T.ty list) :
-    T.TypeVarId.id -> 'r T.ty =
+let make_type_subst (var_ids : TypeVarId.id list) (tys : ty list) :
+    TypeVarId.id -> ty =
   let ls = List.combine var_ids tys in
   let mp =
     List.fold_left
-      (fun mp (k, v) -> T.TypeVarId.Map.add k v mp)
-      T.TypeVarId.Map.empty ls
+      (fun mp (k, v) -> TypeVarId.Map.add k v mp)
+      TypeVarId.Map.empty ls
   in
-  fun id -> T.TypeVarId.Map.find id mp
+  fun id -> TypeVarId.Map.find id mp
 
-let make_type_subst_from_vars (vars : T.type_var list) (tys : 'r T.ty list) :
-    T.TypeVarId.id -> 'r T.ty =
-  make_type_subst (List.map (fun (x : T.type_var) -> x.T.index) vars) tys
+let make_type_subst_from_vars (vars : type_var list) (tys : ty list) :
+    TypeVarId.id -> ty =
+  make_type_subst (List.map (fun (x : type_var) -> x.index) vars) tys
 
 (** Create a const generic substitution from a list of const generic variable ids and a list of
     const generics (with which to substitute the const generic variable ids) *)
-let make_const_generic_subst (var_ids : T.ConstGenericVarId.id list)
-    (cgs : T.const_generic list) : T.ConstGenericVarId.id -> T.const_generic =
+let make_const_generic_subst (var_ids : ConstGenericVarId.id list)
+    (cgs : const_generic list) : ConstGenericVarId.id -> const_generic =
   let ls = List.combine var_ids cgs in
   let mp =
     List.fold_left
-      (fun mp (k, v) -> T.ConstGenericVarId.Map.add k v mp)
-      T.ConstGenericVarId.Map.empty ls
+      (fun mp (k, v) -> ConstGenericVarId.Map.add k v mp)
+      ConstGenericVarId.Map.empty ls
   in
-  fun id -> T.ConstGenericVarId.Map.find id mp
+  fun id -> ConstGenericVarId.Map.find id mp
 
-let make_const_generic_subst_from_vars (vars : T.const_generic_var list)
-    (cgs : T.const_generic list) : T.ConstGenericVarId.id -> T.const_generic =
+let make_const_generic_subst_from_vars (vars : const_generic_var list)
+    (cgs : const_generic list) : ConstGenericVarId.id -> const_generic =
   make_const_generic_subst
-    (List.map (fun (x : T.const_generic_var) -> x.T.index) vars)
+    (List.map (fun (x : const_generic_var) -> x.index) vars)
     cgs
 
 (** Create a trait substitution from a list of trait clause ids and a list of
     trait refs *)
-let make_trait_subst (clause_ids : T.TraitClauseId.id list)
-    (trs : 'r T.trait_ref list) : T.TraitClauseId.id -> 'r T.trait_instance_id =
+let make_trait_subst (clause_ids : TraitClauseId.id list) (trs : trait_ref list)
+    : TraitClauseId.id -> trait_instance_id =
   let ls = List.combine clause_ids trs in
   let mp =
     List.fold_left
-      (fun mp (k, v) -> T.TraitClauseId.Map.add k (T.TraitRef v) mp)
-      T.TraitClauseId.Map.empty ls
+      (fun mp (k, v) -> TraitClauseId.Map.add k (TraitRef v) mp)
+      TraitClauseId.Map.empty ls
   in
-  fun id -> T.TraitClauseId.Map.find id mp
+  fun id -> TraitClauseId.Map.find id mp
 
-let make_trait_subst_from_clauses (clauses : T.trait_clause list)
-    (trs : 'r T.trait_ref list) : T.TraitClauseId.id -> 'r T.trait_instance_id =
+let make_trait_subst_from_clauses (clauses : trait_clause list)
+    (trs : trait_ref list) : TraitClauseId.id -> trait_instance_id =
   make_trait_subst
-    (List.map (fun (x : T.trait_clause) -> x.T.clause_id) clauses)
+    (List.map (fun (x : trait_clause) -> x.clause_id) clauses)
     trs
 
-let make_subst_from_generics (params : T.generic_params)
-    (args : 'r T.region T.generic_args)
-    (tr_self : 'r T.region T.trait_instance_id) :
-    (T.region_var_id T.region, 'r T.region) subst =
-  let r_subst = make_region_subst_from_vars params.T.regions args.T.regions in
-  let ty_subst = make_type_subst_from_vars params.T.types args.T.types in
+let make_subst_from_generics (params : generic_params) (args : generic_args)
+    (tr_self : trait_instance_id) : subst =
+  let r_subst = make_region_subst_from_vars params.regions args.regions in
+  let ty_subst = make_type_subst_from_vars params.types args.types in
   let cg_subst =
-    make_const_generic_subst_from_vars params.T.const_generics
-      args.T.const_generics
+    make_const_generic_subst_from_vars params.const_generics args.const_generics
   in
   let tr_subst =
-    make_trait_subst_from_clauses params.T.trait_clauses args.T.trait_refs
+    make_trait_subst_from_clauses params.trait_clauses args.trait_refs
   in
   { r_subst; ty_subst; cg_subst; tr_subst; tr_self }
 
-let make_subst_from_generics_no_regions :
-      'r.
-      T.generic_params ->
-      'r T.generic_args ->
-      'r T.trait_instance_id ->
-      (T.region_var_id T.region, 'r) subst =
- fun params args tr_self ->
-  let r_subst _ = raise (Failure "Unexpected region") in
-  let ty_subst = make_type_subst_from_vars params.T.types args.T.types in
-  let cg_subst =
-    make_const_generic_subst_from_vars params.T.const_generics
-      args.T.const_generics
-  in
-  let tr_subst =
-    make_trait_subst_from_clauses params.T.trait_clauses args.T.trait_refs
-  in
-  { r_subst; ty_subst; cg_subst; tr_subst; tr_self }
-
-let make_esubst_from_generics (params : T.generic_params)
-    (generics : T.egeneric_args) (tr_self : T.etrait_instance_id) =
-  let r_subst _ = T.Erased in
-  let ty_subst = make_type_subst_from_vars params.types generics.T.types in
-  let cg_subst =
-    make_const_generic_subst_from_vars params.const_generics
-      generics.T.const_generics
-  in
-  let tr_subst =
-    make_trait_subst_from_clauses params.trait_clauses generics.T.trait_refs
-  in
-  { r_subst; ty_subst; cg_subst; tr_subst; tr_self }
+let make_subst_from_generics_erase_regions (params : generic_params)
+    (generics : generic_args) (tr_self : trait_instance_id) =
+  let generics = generic_args_erase_regions generics in
+  let tr_self = trait_instance_id_erase_regions tr_self in
+  let subst = make_subst_from_generics params generics tr_self in
+  { subst with r_subst = (fun _ -> RErased) }
 
 (** Instantiate the type variables in an ADT definition, and return, for
     every variant, the list of the types of its fields.
@@ -237,27 +219,25 @@ let make_esubst_from_generics (params : T.generic_params)
     **IMPORTANT**: this function doesn't normalize the types, you may want to
     use the [AssociatedTypes] equivalent instead.
 *)
-let type_decl_get_instantiated_variants_fields_rtypes (def : T.type_decl)
-    (generics : T.rgeneric_args) : (T.VariantId.id option * T.rty list) list =
+let type_decl_get_instantiated_variants_fields_types (def : type_decl)
+    (generics : generic_args) : (VariantId.id option * ty list) list =
   (* There shouldn't be any reference to Self *)
-  let tr_self = T.UnknownTrait __FUNCTION__ in
-  let subst = make_subst_from_generics def.T.generics generics tr_self in
-  let (variants_fields : (T.VariantId.id option * T.field list) list) =
-    match def.T.kind with
-    | T.Enum variants ->
-        List.mapi
-          (fun i v -> (Some (T.VariantId.of_int i), v.T.fields))
-          variants
-    | T.Struct fields -> [ (None, fields) ]
-    | T.Opaque ->
+  let tr_self = UnknownTrait __FUNCTION__ in
+  let subst = make_subst_from_generics def.generics generics tr_self in
+  let (variants_fields : (VariantId.id option * field list) list) =
+    match def.kind with
+    | Enum variants ->
+        List.mapi (fun i v -> (Some (VariantId.of_int i), v.fields)) variants
+    | Struct fields -> [ (None, fields) ]
+    | Opaque ->
         raise
           (Failure
              ("Can't retrieve the variants of an opaque type: "
-             ^ Names.name_to_string def.name))
+            ^ show_name def.name))
   in
   List.map
     (fun (id, fields) ->
-      (id, List.map (fun f -> ty_substitute subst f.T.field_ty) fields))
+      (id, List.map (fun f -> ty_substitute subst f.field_ty) fields))
     variants_fields
 
 (** Instantiate the type variables in an ADT definition, and return the list
@@ -266,17 +246,16 @@ let type_decl_get_instantiated_variants_fields_rtypes (def : T.type_decl)
     **IMPORTANT**: this function doesn't normalize the types, you may want to
     use the [AssociatedTypes] equivalent instead.
 *)
-let type_decl_get_instantiated_field_rtypes (def : T.type_decl)
-    (opt_variant_id : T.VariantId.id option) (generics : T.rgeneric_args) :
-    T.rty list =
+let type_decl_get_instantiated_field_types (def : type_decl)
+    (opt_variant_id : VariantId.id option) (generics : generic_args) : ty list =
   (* For now, check that there are no clauses - otherwise we might need
      to normalize the types *)
   assert (def.generics.trait_clauses = []);
   (* There shouldn't be any reference to Self *)
-  let tr_self = T.UnknownTrait __FUNCTION__ in
-  let subst = make_subst_from_generics def.T.generics generics tr_self in
-  let fields = TU.type_decl_get_fields def opt_variant_id in
-  List.map (fun f -> ty_substitute subst f.T.field_ty) fields
+  let tr_self = UnknownTrait __FUNCTION__ in
+  let subst = make_subst_from_generics def.generics generics tr_self in
+  let fields = type_decl_get_fields def opt_variant_id in
+  List.map (fun f -> ty_substitute subst f.field_ty) fields
 
 (** Return the types of the properly instantiated ADT's variant, provided a
     context.
@@ -284,11 +263,11 @@ let type_decl_get_instantiated_field_rtypes (def : T.type_decl)
     **IMPORTANT**: this function doesn't normalize the types, you may want to
     use the [AssociatedTypes] equivalent instead.
 *)
-let ctx_adt_get_instantiated_field_rtypes (ctx : C.eval_ctx)
-    (def_id : T.TypeDeclId.id) (opt_variant_id : T.VariantId.id option)
-    (generics : T.rgeneric_args) : T.rty list =
-  let def = C.ctx_lookup_type_decl ctx def_id in
-  type_decl_get_instantiated_field_rtypes def opt_variant_id generics
+let ctx_adt_get_instantiated_field_types (ctx : eval_ctx)
+    (def_id : TypeDeclId.id) (opt_variant_id : VariantId.id option)
+    (generics : generic_args) : ty list =
+  let def = ctx_lookup_type_decl ctx def_id in
+  type_decl_get_instantiated_field_types def opt_variant_id generics
 
 (** Return the types of the properly instantiated ADT value (note that
     here, ADT is understood in its broad meaning: ADT, assumed value or tuple).
@@ -296,175 +275,106 @@ let ctx_adt_get_instantiated_field_rtypes (ctx : C.eval_ctx)
     **IMPORTANT**: this function doesn't normalize the types, you may want to
     use the [AssociatedTypes] equivalent instead.
  *)
-let ctx_adt_value_get_instantiated_field_rtypes (ctx : C.eval_ctx)
-    (adt : V.adt_value) (id : T.type_id) (generics : T.rgeneric_args) :
-    T.rty list =
+let ctx_adt_value_get_instantiated_field_types (ctx : eval_ctx)
+    (adt : adt_value) (id : type_id) (generics : generic_args) : ty list =
   match id with
-  | T.AdtId id ->
+  | TAdtId id ->
       (* Retrieve the types of the fields *)
-      ctx_adt_get_instantiated_field_rtypes ctx id adt.V.variant_id generics
-  | T.Tuple ->
+      ctx_adt_get_instantiated_field_types ctx id adt.variant_id generics
+  | TTuple ->
       assert (generics.regions = []);
       generics.types
-  | T.Assumed aty -> (
+  | TAssumed aty -> (
       match aty with
-      | T.Box ->
+      | TBox ->
           assert (generics.regions = []);
           assert (List.length generics.types = 1);
           assert (generics.const_generics = []);
           generics.types
-      | T.Array | T.Slice | T.Str ->
+      | TArray | TSlice | TStr ->
           (* Those types don't have fields *)
           raise (Failure "Unreachable"))
 
-(** Instantiate the type variables in an ADT definition, and return the list
-    of types of the fields for the chosen variant.
-
-    **IMPORTANT**: this function doesn't normalize the types, you may want to
-    use the [AssociatedTypes] equivalent instead.
-*)
-let type_decl_get_instantiated_field_etypes (def : T.type_decl)
-    (opt_variant_id : T.VariantId.id option) (generics : T.egeneric_args) :
-    T.ety list =
-  (* For now, check that there are no clauses - otherwise we might need
-     to normalize the types *)
-  assert (def.generics.trait_clauses = []);
-  (* There shouldn't be any reference to Self *)
-  let tr_self : T.erased_region T.trait_instance_id =
-    T.UnknownTrait __FUNCTION__
-  in
-  let { r_subst = _; ty_subst; cg_subst; tr_subst; tr_self } =
-    make_esubst_from_generics def.T.generics generics tr_self
-  in
-  let fields = TU.type_decl_get_fields def opt_variant_id in
-  List.map
-    (fun (f : T.field) ->
-      erase_regions_substitute_types ty_subst cg_subst tr_subst tr_self
-        f.T.field_ty)
-    fields
-
-(** Return the types of the properly instantiated ADT's variant, provided a
-    context.
-
-    **IMPORTANT**: this function doesn't normalize the types, you may want to
-    use the [AssociatedTypes] equivalent instead.
- *)
-let ctx_adt_get_instantiated_field_etypes (ctx : C.eval_ctx)
-    (def_id : T.TypeDeclId.id) (opt_variant_id : T.VariantId.id option)
-    (generics : T.egeneric_args) : T.ety list =
-  let def = C.ctx_lookup_type_decl ctx def_id in
-  type_decl_get_instantiated_field_etypes def opt_variant_id generics
-
-let statement_substitute_visitor
-    (subst : (T.erased_region, T.erased_region) subst) =
-  (* Keep in synch with [ty_substitute_visitor] *)
-  object
-    inherit [_] A.map_statement
-    method! visit_'r _ r = subst.r_subst r
-    method! visit_TypeVar _ id = subst.ty_subst id
-
-    method! visit_type_var_id _ _ =
-      (* We should never get here because we reimplemented [visit_TypeVar] *)
-      raise (Failure "Unexpected")
-
-    method! visit_ConstGenericVar _ id = subst.cg_subst id
-
-    method! visit_const_generic_var_id _ _ =
-      (* We should never get here because we reimplemented [visit_Var] *)
-      raise (Failure "Unexpected")
-
-    method! visit_Clause _ id = subst.tr_subst id
-    method! visit_Self _ = subst.tr_self
-  end
-
 (** Apply a type substitution to a place *)
-let place_substitute (subst : (T.erased_region, T.erased_region) subst)
-    (p : E.place) : E.place =
+let place_substitute (subst : subst) (p : place) : place =
   (* There is in fact nothing to do *)
-  (statement_substitute_visitor subst)#visit_place () p
+  (st_substitute_visitor subst)#visit_place () p
 
 (** Apply a type substitution to an operand *)
-let operand_substitute (subst : (T.erased_region, T.erased_region) subst)
-    (op : E.operand) : E.operand =
-  (statement_substitute_visitor subst)#visit_operand () op
+let operand_substitute (subst : subst) (op : operand) : operand =
+  (st_substitute_visitor subst)#visit_operand () op
 
 (** Apply a type substitution to an rvalue *)
-let rvalue_substitute (subst : (T.erased_region, T.erased_region) subst)
-    (rv : E.rvalue) : E.rvalue =
-  (statement_substitute_visitor subst)#visit_rvalue () rv
+let rvalue_substitute (subst : subst) (rv : rvalue) : rvalue =
+  (st_substitute_visitor subst)#visit_rvalue () rv
 
 (** Apply a type substitution to an assertion *)
-let assertion_substitute (subst : (T.erased_region, T.erased_region) subst)
-    (a : A.assertion) : A.assertion =
-  (statement_substitute_visitor subst)#visit_assertion () a
+let assertion_substitute (subst : subst) (a : assertion) : assertion =
+  (st_substitute_visitor subst)#visit_assertion () a
 
 (** Apply a type substitution to a call *)
-let call_substitute (subst : (T.erased_region, T.erased_region) subst)
-    (call : A.call) : A.call =
-  (statement_substitute_visitor subst)#visit_call () call
+let call_substitute (subst : subst) (call : call) : call =
+  (st_substitute_visitor subst)#visit_call () call
 
 (** Apply a type substitution to a statement *)
-let statement_substitute (subst : (T.erased_region, T.erased_region) subst)
-    (st : A.statement) : A.statement =
-  (statement_substitute_visitor subst)#visit_statement () st
+let statement_substitute (subst : subst) (st : statement) : statement =
+  (st_substitute_visitor subst)#visit_statement () st
 
 (** Apply a type substitution to a function body. Return the local variables
     and the body. *)
-let fun_body_substitute_in_body
-    (subst : (T.erased_region, T.erased_region) subst) (body : A.fun_body) :
-    A.var list * A.statement =
+let fun_body_substitute_in_body (subst : subst) (body : fun_body) :
+    var list * statement =
   let locals =
     List.map
-      (fun (v : A.var) -> { v with A.var_ty = ty_substitute subst v.A.var_ty })
-      body.A.locals
+      (fun (v : var) -> { v with var_ty = ty_substitute subst v.var_ty })
+      body.locals
   in
   let body = statement_substitute subst body.body in
   (locals, body)
 
-let trait_type_constraint_substitute (subst : ('r1, 'r2) subst)
-    (ttc : 'r1 T.trait_type_constraint) : 'r2 T.trait_type_constraint =
-  let { T.trait_ref; generics; type_name; ty } = ttc in
-  let visitor = ty_substitute_visitor subst in
+let trait_type_constraint_substitute (subst : subst)
+    (ttc : trait_type_constraint) : trait_type_constraint =
+  let { trait_ref; generics; type_name; ty } = ttc in
+  let visitor = st_substitute_visitor subst in
   let trait_ref = visitor#visit_trait_ref () trait_ref in
   let generics = visitor#visit_generic_args () generics in
   let ty = visitor#visit_ty () ty in
-  { T.trait_ref; generics; type_name; ty }
+  { trait_ref; generics; type_name; ty }
 
-(** Substitute a function signature.
+(** Substitute a function signature, together with the regions hierarchy
+    associated to that signature.
 
     **IMPORTANT:** this function doesn't normalize the types.
  *)
-let substitute_signature (asubst : T.RegionGroupId.id -> V.AbstractionId.id)
-    (r_subst : T.RegionVarId.id -> T.RegionId.id)
-    (ty_subst : T.TypeVarId.id -> T.rty)
-    (cg_subst : T.ConstGenericVarId.id -> T.const_generic)
-    (tr_subst : T.TraitClauseId.id -> T.rtrait_instance_id)
-    (tr_self : T.rtrait_instance_id) (sg : A.fun_sig) : A.inst_fun_sig =
-  let r_subst' (r : T.RegionVarId.id T.region) : T.RegionId.id T.region =
-    match r with T.Static -> T.Static | T.Var rid -> T.Var (r_subst rid)
+let substitute_signature (asubst : RegionGroupId.id -> AbstractionId.id)
+    (r_subst : RegionId.id -> RegionId.id) (ty_subst : TypeVarId.id -> ty)
+    (cg_subst : ConstGenericVarId.id -> const_generic)
+    (tr_subst : TraitClauseId.id -> trait_instance_id)
+    (tr_self : trait_instance_id) (sg : fun_sig)
+    (regions_hierarchy : region_groups) : inst_fun_sig =
+  let r_subst' (r : region) : region =
+    match r with RStatic | RErased -> r | RVar rid -> RVar (r_subst rid)
   in
   let subst = { r_subst = r_subst'; ty_subst; cg_subst; tr_subst; tr_self } in
-  let inputs = List.map (ty_substitute subst) sg.A.inputs in
-  let output = ty_substitute subst sg.A.output in
-  let subst_region_group (rg : T.region_var_group) : A.abs_region_group =
+  let inputs = List.map (ty_substitute subst) sg.inputs in
+  let output = ty_substitute subst sg.output in
+  let subst_region_group (rg : region_group) : abs_region_group =
     let id = asubst rg.id in
     let regions = List.map r_subst rg.regions in
     let parents = List.map asubst rg.parents in
-    { id; regions; parents }
+    ({ id; regions; parents } : abs_region_group)
   in
-  let regions_hierarchy = List.map subst_region_group sg.A.regions_hierarchy in
+  let regions_hierarchy = List.map subst_region_group regions_hierarchy in
   let trait_type_constraints =
     List.map
       (trait_type_constraint_substitute subst)
       sg.preds.trait_type_constraints
   in
-  { A.inputs; output; regions_hierarchy; trait_type_constraints }
+  { inputs; output; regions_hierarchy; trait_type_constraints }
 
 (** Substitute variable identifiers in a type *)
-let ty_substitute_ids (ty_subst : T.TypeVarId.id -> T.TypeVarId.id)
-    (cg_subst : T.ConstGenericVarId.id -> T.ConstGenericVarId.id) (ty : 'r T.ty)
-    : 'r T.ty =
-  let open T in
+let statement_substitute_ids (ty_subst : TypeVarId.id -> TypeVarId.id)
+    (cg_subst : ConstGenericVarId.id -> ConstGenericVarId.id) (ty : ty) : ty =
   let visitor =
     object
       inherit [_] map_ty
@@ -476,143 +386,95 @@ let ty_substitute_ids (ty_subst : T.TypeVarId.id -> T.TypeVarId.id)
 
   visitor#visit_ty () ty
 
-(* This visitor is a mess...
-
-   We want to write a class which visits abstractions, values, etc. *and their
-   types* to substitute identifiers.
-
-   The issue is that we derive two specialized types (ety and rty) from a
-   polymorphic type (ty). Because of this, there are typing issues with
-   [visit_'r] if we define a class which visits objects of types [ety] and [rty]
-   while inheriting a class which visit [ty]...
-*)
-let subst_ids_visitor (r_subst : T.RegionId.id -> T.RegionId.id)
-    (rvsubst : T.RegionVarId.id -> T.RegionVarId.id)
-    (ty_subst : T.TypeVarId.id -> T.TypeVarId.id)
-    (cg_subst : T.ConstGenericVarId.id -> T.ConstGenericVarId.id)
-    (ssubst : V.SymbolicValueId.id -> V.SymbolicValueId.id)
-    (bsubst : V.BorrowId.id -> V.BorrowId.id)
-    (asubst : V.AbstractionId.id -> V.AbstractionId.id) =
-  let subst_rty =
-    object
-      inherit [_] T.map_ty
-
-      method visit_'r _ r =
-        match r with T.Static -> T.Static | T.Var rid -> T.Var (r_subst rid)
-
-      method! visit_type_var_id _ id = ty_subst id
-      method! visit_const_generic_var_id _ id = cg_subst id
-    end
-  in
-
-  let visitor =
-    object (self : 'self)
-      inherit [_] C.map_env
-      method! visit_borrow_id _ bid = bsubst bid
-      method! visit_loan_id _ bid = bsubst bid
-      method! visit_ety _ ty = ty_substitute_ids ty_subst cg_subst ty
-      method! visit_rty env ty = subst_rty#visit_ty env ty
-      method! visit_symbolic_value_id _ id = ssubst id
-
-      (** We *do* visit meta-values *)
-      method! visit_msymbolic_value env sv = self#visit_symbolic_value env sv
-
-      (** We *do* visit meta-values *)
-      method! visit_mvalue env v = self#visit_typed_value env v
-
-      method! visit_region_id _ id = r_subst id
-      method! visit_region_var_id _ id = rvsubst id
-      method! visit_abstraction_id _ id = asubst id
-    end
-  in
-
-  object
-    method visit_ety (x : T.ety) : T.ety = visitor#visit_ety () x
-    method visit_rty (x : T.rty) : T.rty = visitor#visit_rty () x
-
-    method visit_typed_value (x : V.typed_value) : V.typed_value =
-      visitor#visit_typed_value () x
-
-    method visit_typed_avalue (x : V.typed_avalue) : V.typed_avalue =
-      visitor#visit_typed_avalue () x
-
-    method visit_abs (x : V.abs) : V.abs = visitor#visit_abs () x
-    method visit_env (env : C.env) : C.env = visitor#visit_env () env
+let subst_ids_visitor (r_subst : RegionId.id -> RegionId.id)
+    (ty_subst : TypeVarId.id -> TypeVarId.id)
+    (cg_subst : ConstGenericVarId.id -> ConstGenericVarId.id)
+    (ssubst : SymbolicValueId.id -> SymbolicValueId.id)
+    (bsubst : BorrowId.id -> BorrowId.id)
+    (asubst : AbstractionId.id -> AbstractionId.id) =
+  object (self : 'self)
+    inherit [_] map_env
+    method! visit_type_var_id _ id = ty_subst id
+    method! visit_const_generic_var_id _ id = cg_subst id
+    method! visit_region_id _ rid = r_subst rid
+    method! visit_borrow_id _ bid = bsubst bid
+    method! visit_loan_id _ bid = bsubst bid
+    method! visit_symbolic_value_id _ id = ssubst id
+
+    (** We *do* visit meta-values *)
+    method! visit_msymbolic_value env sv = self#visit_symbolic_value env sv
+
+    (** We *do* visit meta-values *)
+    method! visit_mvalue env v = self#visit_typed_value env v
+
+    method! visit_abstraction_id _ id = asubst id
   end
 
-let typed_value_subst_ids (r_subst : T.RegionId.id -> T.RegionId.id)
-    (rvsubst : T.RegionVarId.id -> T.RegionVarId.id)
-    (ty_subst : T.TypeVarId.id -> T.TypeVarId.id)
-    (cg_subst : T.ConstGenericVarId.id -> T.ConstGenericVarId.id)
-    (ssubst : V.SymbolicValueId.id -> V.SymbolicValueId.id)
-    (bsubst : V.BorrowId.id -> V.BorrowId.id) (v : V.typed_value) :
-    V.typed_value =
+let typed_value_subst_ids (r_subst : RegionId.id -> RegionId.id)
+    (ty_subst : TypeVarId.id -> TypeVarId.id)
+    (cg_subst : ConstGenericVarId.id -> ConstGenericVarId.id)
+    (ssubst : SymbolicValueId.id -> SymbolicValueId.id)
+    (bsubst : BorrowId.id -> BorrowId.id) (v : typed_value) : typed_value =
   let asubst _ = raise (Failure "Unreachable") in
-  (subst_ids_visitor r_subst rvsubst ty_subst cg_subst ssubst bsubst asubst)
-    #visit_typed_value v
+  let vis = subst_ids_visitor r_subst ty_subst cg_subst ssubst bsubst asubst in
+  vis#visit_typed_value () v
 
-let typed_value_subst_rids (r_subst : T.RegionId.id -> T.RegionId.id)
-    (v : V.typed_value) : V.typed_value =
+let typed_value_subst_rids (r_subst : RegionId.id -> RegionId.id)
+    (v : typed_value) : typed_value =
   typed_value_subst_ids r_subst
     (fun x -> x)
     (fun x -> x)
     (fun x -> x)
     (fun x -> x)
-    (fun x -> x)
     v
 
-let typed_avalue_subst_ids (r_subst : T.RegionId.id -> T.RegionId.id)
-    (rvsubst : T.RegionVarId.id -> T.RegionVarId.id)
-    (ty_subst : T.TypeVarId.id -> T.TypeVarId.id)
-    (cg_subst : T.ConstGenericVarId.id -> T.ConstGenericVarId.id)
-    (ssubst : V.SymbolicValueId.id -> V.SymbolicValueId.id)
-    (bsubst : V.BorrowId.id -> V.BorrowId.id) (v : V.typed_avalue) :
-    V.typed_avalue =
+let typed_avalue_subst_ids (r_subst : RegionId.id -> RegionId.id)
+    (ty_subst : TypeVarId.id -> TypeVarId.id)
+    (cg_subst : ConstGenericVarId.id -> ConstGenericVarId.id)
+    (ssubst : SymbolicValueId.id -> SymbolicValueId.id)
+    (bsubst : BorrowId.id -> BorrowId.id) (v : typed_avalue) : typed_avalue =
   let asubst _ = raise (Failure "Unreachable") in
-  (subst_ids_visitor r_subst rvsubst ty_subst cg_subst ssubst bsubst asubst)
-    #visit_typed_avalue v
-
-let abs_subst_ids (r_subst : T.RegionId.id -> T.RegionId.id)
-    (rvsubst : T.RegionVarId.id -> T.RegionVarId.id)
-    (ty_subst : T.TypeVarId.id -> T.TypeVarId.id)
-    (cg_subst : T.ConstGenericVarId.id -> T.ConstGenericVarId.id)
-    (ssubst : V.SymbolicValueId.id -> V.SymbolicValueId.id)
-    (bsubst : V.BorrowId.id -> V.BorrowId.id)
-    (asubst : V.AbstractionId.id -> V.AbstractionId.id) (x : V.abs) : V.abs =
-  (subst_ids_visitor r_subst rvsubst ty_subst cg_subst ssubst bsubst asubst)
-    #visit_abs x
-
-let env_subst_ids (r_subst : T.RegionId.id -> T.RegionId.id)
-    (rvsubst : T.RegionVarId.id -> T.RegionVarId.id)
-    (ty_subst : T.TypeVarId.id -> T.TypeVarId.id)
-    (cg_subst : T.ConstGenericVarId.id -> T.ConstGenericVarId.id)
-    (ssubst : V.SymbolicValueId.id -> V.SymbolicValueId.id)
-    (bsubst : V.BorrowId.id -> V.BorrowId.id)
-    (asubst : V.AbstractionId.id -> V.AbstractionId.id) (x : C.env) : C.env =
-  (subst_ids_visitor r_subst rvsubst ty_subst cg_subst ssubst bsubst asubst)
-    #visit_env x
-
-let typed_avalue_subst_rids (r_subst : T.RegionId.id -> T.RegionId.id)
-    (x : V.typed_avalue) : V.typed_avalue =
+  let vis = subst_ids_visitor r_subst ty_subst cg_subst ssubst bsubst asubst in
+  vis#visit_typed_avalue () v
+
+let abs_subst_ids (r_subst : RegionId.id -> RegionId.id)
+    (ty_subst : TypeVarId.id -> TypeVarId.id)
+    (cg_subst : ConstGenericVarId.id -> ConstGenericVarId.id)
+    (ssubst : SymbolicValueId.id -> SymbolicValueId.id)
+    (bsubst : BorrowId.id -> BorrowId.id)
+    (asubst : AbstractionId.id -> AbstractionId.id) (x : abs) : abs =
+  let vis = subst_ids_visitor r_subst ty_subst cg_subst ssubst bsubst asubst in
+  vis#visit_abs () x
+
+let env_subst_ids (r_subst : RegionId.id -> RegionId.id)
+    (ty_subst : TypeVarId.id -> TypeVarId.id)
+    (cg_subst : ConstGenericVarId.id -> ConstGenericVarId.id)
+    (ssubst : SymbolicValueId.id -> SymbolicValueId.id)
+    (bsubst : BorrowId.id -> BorrowId.id)
+    (asubst : AbstractionId.id -> AbstractionId.id) (x : env) : env =
+  let vis = subst_ids_visitor r_subst ty_subst cg_subst ssubst bsubst asubst in
+  vis#visit_env () x
+
+let typed_avalue_subst_rids (r_subst : RegionId.id -> RegionId.id)
+    (x : typed_avalue) : typed_avalue =
   let asubst _ = raise (Failure "Unreachable") in
-  (subst_ids_visitor r_subst
-     (fun x -> x)
-     (fun x -> x)
-     (fun x -> x)
-     (fun x -> x)
-     (fun x -> x)
-     asubst)
-    #visit_typed_avalue
-    x
-
-let env_subst_rids (r_subst : T.RegionId.id -> T.RegionId.id) (x : C.env) :
-    C.env =
-  (subst_ids_visitor r_subst
-     (fun x -> x)
-     (fun x -> x)
-     (fun x -> x)
-     (fun x -> x)
-     (fun x -> x)
-     (fun x -> x))
-    #visit_env
-    x
+  let vis =
+    subst_ids_visitor r_subst
+      (fun x -> x)
+      (fun x -> x)
+      (fun x -> x)
+      (fun x -> x)
+      asubst
+  in
+  vis#visit_typed_avalue () x
+
+let env_subst_rids (r_subst : RegionId.id -> RegionId.id) (x : env) : env =
+  let vis =
+    subst_ids_visitor r_subst
+      (fun x -> x)
+      (fun x -> x)
+      (fun x -> x)
+      (fun x -> x)
+      (fun x -> x)
+  in
+  vis#visit_env () x
diff --git a/compiler/SymbolicAst.ml b/compiler/SymbolicAst.ml
index 4df8fec7..a9f45926 100644
--- a/compiler/SymbolicAst.ml
+++ b/compiler/SymbolicAst.ml
@@ -3,10 +3,10 @@
     the symbolic execution: we later apply transformations to generate the
     pure AST that we export. *)
 
-module T = Types
-module V = Values
-module E = Expressions
-module A = LlbcAst
+open Types
+open Expressions
+open Values
+open LlbcAst
 
 (** "Meta"-place: a place stored as meta-data.
 
@@ -23,16 +23,16 @@ type mplace = {
           because the most important information in a place is the name of the
           variable!
        *)
-  projection : E.projection;
+  projection : projection;
       (** We store the projection because we can, but it is actually not that useful *)
 }
 [@@deriving show]
 
 type call_id =
-  | Fun of A.fun_id_or_trait_method_ref * V.FunCallId.id
+  | Fun of fun_id_or_trait_method_ref * FunCallId.id
       (** A "regular" function (i.e., a function which is not a primitive operation) *)
-  | Unop of E.unop
-  | Binop of E.binop
+  | Unop of unop
+  | Binop of binop
 [@@deriving show, ord]
 
 type call = {
@@ -42,60 +42,52 @@ type call = {
           evaluated). We need it to compute the translated values for shared
           borrows (we need to perform lookups).
        *)
-  abstractions : V.AbstractionId.id list;
-  generics : T.egeneric_args;
-  args : V.typed_value list;
+  abstractions : AbstractionId.id list;
+  generics : generic_args;
+  args : typed_value list;
   args_places : mplace option list;  (** Meta information *)
-  dest : V.symbolic_value;
+  dest : symbolic_value;
   dest_place : mplace option;  (** Meta information *)
 }
 [@@deriving show]
 
-(** Meta information, not necessary for synthesis but useful to guide it to
-    generate a pretty output.
+(** Meta information for expressions, not necessary for synthesis but useful to
+    guide it to generate a pretty output.
  *)
-
-type meta =
-  | Assignment of Contexts.eval_ctx * mplace * V.typed_value * mplace option
+type emeta =
+  | Assignment of Contexts.eval_ctx * mplace * typed_value * mplace option
       (** We generated an assignment (destination, assigned value, src) *)
 [@@deriving show]
 
-type variant_id = T.VariantId.id [@@deriving show]
-type global_decl_id = A.GlobalDeclId.id [@@deriving show]
-type 'a symbolic_value_id_map = 'a V.SymbolicValueId.Map.t [@@deriving show]
-type 'a region_group_id_map = 'a T.RegionGroupId.Map.t [@@deriving show]
+type variant_id = VariantId.id [@@deriving show]
+type global_decl_id = GlobalDeclId.id [@@deriving show]
+type 'a symbolic_value_id_map = 'a SymbolicValueId.Map.t [@@deriving show]
+type 'a region_group_id_map = 'a RegionGroupId.Map.t [@@deriving show]
+
+(** Ancestor for {!expression} iter visitor.
 
-(** Ancestor for {!expression} iter visitor *)
+    We could make it inherit the visitor for {!eval_ctx}, but in all the uses
+    of this visitor we don't need to explore {!eval_ctx}, so we make it inherit
+    the abstraction visitors instead.
+ *)
 class ['self] iter_expression_base =
   object (self : 'self)
-    inherit [_] VisitorsRuntime.iter
+    inherit [_] iter_abs
     method visit_eval_ctx : 'env -> Contexts.eval_ctx -> unit = fun _ _ -> ()
-    method visit_typed_value : 'env -> V.typed_value -> unit = fun _ _ -> ()
     method visit_call : 'env -> call -> unit = fun _ _ -> ()
-    method visit_abs : 'env -> V.abs -> unit = fun _ _ -> ()
-    method visit_loop_id : 'env -> V.loop_id -> unit = fun _ _ -> ()
-    method visit_variant_id : 'env -> variant_id -> unit = fun _ _ -> ()
+    method visit_loop_id : 'env -> loop_id -> unit = fun _ _ -> ()
 
-    method visit_const_generic_var_id : 'env -> T.const_generic_var_id -> unit =
+    method visit_region_group_id : 'env -> RegionGroupId.id -> unit =
       fun _ _ -> ()
 
-    method visit_symbolic_value_id : 'env -> V.symbolic_value_id -> unit =
-      fun _ _ -> ()
-
-    method visit_symbolic_value : 'env -> V.symbolic_value -> unit =
-      fun _ _ -> ()
-
-    method visit_region_group_id : 'env -> T.RegionGroupId.id -> unit =
-      fun _ _ -> ()
-
-    method visit_global_decl_id : 'env -> global_decl_id -> unit = fun _ _ -> ()
     method visit_mplace : 'env -> mplace -> unit = fun _ _ -> ()
-    method visit_meta : 'env -> meta -> unit = fun _ _ -> ()
+    method visit_emeta : 'env -> emeta -> unit = fun _ _ -> ()
+    method visit_meta : 'env -> Meta.meta -> unit = fun _ _ -> ()
 
     method visit_region_group_id_map
         : 'a. ('env -> 'a -> unit) -> 'env -> 'a region_group_id_map -> unit =
       fun f env m ->
-        T.RegionGroupId.Map.iter
+        RegionGroupId.Map.iter
           (fun id x ->
             self#visit_region_group_id env id;
             f env x)
@@ -104,25 +96,17 @@ class ['self] iter_expression_base =
     method visit_symbolic_value_id_map
         : 'a. ('env -> 'a -> unit) -> 'env -> 'a symbolic_value_id_map -> unit =
       fun f env m ->
-        V.SymbolicValueId.Map.iter
+        SymbolicValueId.Map.iter
           (fun id x ->
             self#visit_symbolic_value_id env id;
             f env x)
           m
 
-    method visit_symbolic_value_id_set : 'env -> V.symbolic_value_id_set -> unit
-        =
-      fun env s ->
-        V.SymbolicValueId.Set.iter (self#visit_symbolic_value_id env) s
+    method visit_symbolic_value_id_set : 'env -> symbolic_value_id_set -> unit =
+      fun env s -> SymbolicValueId.Set.iter (self#visit_symbolic_value_id env) s
 
-    method visit_integer_type : 'env -> T.integer_type -> unit = fun _ _ -> ()
-    method visit_scalar_value : 'env -> V.scalar_value -> unit = fun _ _ -> ()
-
-    method visit_symbolic_expansion : 'env -> V.symbolic_expansion -> unit =
+    method visit_symbolic_expansion : 'env -> symbolic_expansion -> unit =
       fun _ _ -> ()
-
-    method visit_etrait_ref : 'env -> T.etrait_ref -> unit = fun _ _ -> ()
-    method visit_egeneric_args : 'env -> T.egeneric_args -> unit = fun _ _ -> ()
   end
 
 (** **Rem.:** here, {!expression} is not at all equivalent to the expressions
@@ -130,7 +114,7 @@ class ['self] iter_expression_base =
     lambda-calculus expressions.
  *)
 type expression =
-  | Return of Contexts.eval_ctx * V.typed_value option
+  | Return of Contexts.eval_ctx * typed_value option
       (** There are two cases:
           - the AST is for a forward function: the typed value should contain
             the value which was in the return variable
@@ -142,22 +126,22 @@ type expression =
        *)
   | Panic
   | FunCall of call * expression
-  | EndAbstraction of Contexts.eval_ctx * V.abs * expression
+  | EndAbstraction of Contexts.eval_ctx * abs * expression
       (** The context is the evaluation context upon ending the abstraction,
           just after we removed the abstraction from the context.
 
           The context is the evaluation context from after evaluating the asserted
           value. It has the same purpose as for the {!Return} case.
        *)
-  | EvalGlobal of global_decl_id * V.symbolic_value * expression
+  | EvalGlobal of global_decl_id * symbolic_value * expression
       (** Evaluate a global to a fresh symbolic value *)
-  | Assertion of Contexts.eval_ctx * V.typed_value * expression
+  | Assertion of Contexts.eval_ctx * typed_value * expression
       (** An assertion.
 
           The context is the evaluation context from after evaluating the asserted
           value. It has the same purpose as for the {!Return} case.
        *)
-  | Expansion of mplace option * V.symbolic_value * expansion
+  | Expansion of mplace option * symbolic_value * expansion
       (** Expansion of a symbolic value.
     
           The place is "meta": it gives the path to the symbolic value (if available)
@@ -169,7 +153,7 @@ type expression =
   | IntroSymbolic of
       Contexts.eval_ctx
       * mplace option
-      * V.symbolic_value
+      * symbolic_value
       * value_aggregate
       * expression
       (** We introduce a new symbolic value, equal to some other value.
@@ -185,7 +169,7 @@ type expression =
        *)
   | ForwardEnd of
       Contexts.eval_ctx
-      * V.typed_value symbolic_value_id_map option
+      * typed_value symbolic_value_id_map option
       * expression
       * expression region_group_id_map
       (** We use this delimiter to indicate at which point we switch to the
@@ -207,7 +191,7 @@ type expression =
           comments for the {!Return} variant).
        *)
   | Loop of loop  (** Loop *)
-  | ReturnWithLoop of V.loop_id * bool
+  | ReturnWithLoop of loop_id * bool
       (** End the function with a call to a loop function.
 
           This encompasses the cases when we synthesize a function body
@@ -216,25 +200,26 @@ type expression =
 
           The boolean is [is_continue].
        *)
-  | Meta of meta * expression  (** Meta information *)
+  | Meta of emeta * expression  (** Meta information *)
 
 and loop = {
-  loop_id : V.loop_id;
-  input_svalues : V.symbolic_value list;  (** The input symbolic values *)
-  fresh_svalues : V.symbolic_value_id_set;
+  loop_id : loop_id;
+  input_svalues : symbolic_value list;  (** The input symbolic values *)
+  fresh_svalues : symbolic_value_id_set;
       (** The symbolic values introduced by the loop fixed-point *)
   rg_to_given_back_tys :
-    ((T.RegionId.Set.t * T.rty list) T.RegionGroupId.Map.t[@opaque]);
+    ((RegionId.Set.t * ty list) RegionGroupId.Map.t[@opaque]);
       (** The map from region group ids to the types of the values given back
           by the corresponding loop abstractions.
        *)
   end_expr : expression;
       (** The end of the function (upon the moment it enters the loop) *)
   loop_expr : expression;  (** The symbolically executed loop body *)
+  meta : Meta.meta;  (** Information about where the origin of the loop body *)
 }
 
 and expansion =
-  | ExpandNoBranch of V.symbolic_expansion * expression
+  | ExpandNoBranch of symbolic_expansion * expression
       (** A symbolic expansion which doesn't generate a branching.
           Includes:
           - concrete expansion
@@ -242,25 +227,24 @@ and expansion =
           *Doesn't* include:
           - expansion of ADTs with one variant
        *)
-  | ExpandAdt of (variant_id option * V.symbolic_value list * expression) list
+  | ExpandAdt of (variant_id option * symbolic_value list * expression) list
       (** ADT expansion *)
   | ExpandBool of expression * expression
       (** A boolean expansion (i.e, an [if ... then ... else ...]) *)
-  | ExpandInt of
-      T.integer_type * (V.scalar_value * expression) list * expression
+  | ExpandInt of integer_type * (scalar_value * expression) list * expression
       (** An integer expansion (i.e, a switch over an integer). The last
           expression is for the "otherwise" branch. *)
 
 (* Remark: this type doesn't have to be mutually recursive with the other
    types, but it makes it easy to generate the visitors *)
 and value_aggregate =
-  | SingleValue of V.typed_value  (** Regular case *)
-  | Array of V.typed_value list
+  | VaSingleValue of typed_value  (** Regular case *)
+  | VaArray of typed_value list
       (** This is used when introducing array aggregates *)
-  | ConstGenericValue of T.const_generic_var_id
+  | VaCgValue of const_generic_var_id
       (** This is used when evaluating a const generic value: in the interpreter,
           we introduce a fresh symbolic value. *)
-  | TraitConstValue of T.etrait_ref * T.egeneric_args * string
+  | VaTraitConstValue of trait_ref * generic_args * string
       (** A trait constant value *)
 [@@deriving
   show,
diff --git a/compiler/SymbolicToPure.ml b/compiler/SymbolicToPure.ml
index 2ce8c706..4df3ee73 100644
--- a/compiler/SymbolicToPure.ml
+++ b/compiler/SymbolicToPure.ml
@@ -2,18 +2,18 @@ open Utils
 open LlbcAstUtils
 open Pure
 open PureUtils
-module Id = Identifiers
+open InterpreterUtils
+open FunsAnalysis
+open TypesAnalysis
+module T = Types
+module V = Values
 module C = Contexts
 module A = LlbcAst
 module S = SymbolicAst
-module TA = TypesAnalysis
-module L = Logging
 module PP = PrintPure
-module FA = FunsAnalysis
-module IU = InterpreterUtils
 
 (** The local logger *)
-let log = L.symbolic_to_pure_log
+let log = Logging.symbolic_to_pure_log
 
 type type_context = {
   llbc_type_decls : T.type_decl TypeDeclId.Map.t;
@@ -23,7 +23,7 @@ type type_context = {
           This map is empty when we translate the types, then contains all
           the translated types when we translate the functions.
        *)
-  type_infos : TA.type_infos;
+  type_infos : type_infos;
   recursive_decls : T.TypeDeclId.Set.t;
 }
 [@@deriving show]
@@ -46,7 +46,8 @@ type fun_sig_named_outputs = {
 type fun_context = {
   llbc_fun_decls : A.fun_decl A.FunDeclId.Map.t;
   fun_sigs : fun_sig_named_outputs RegularFunIdNotLoopMap.t;  (** *)
-  fun_infos : FA.fun_info A.FunDeclId.Map.t;
+  fun_infos : fun_info A.FunDeclId.Map.t;
+  regions_hierarchies : T.region_groups FunIdMap.t;
 }
 [@@deriving show]
 
@@ -207,116 +208,96 @@ type bs_ctx = {
 [@@deriving show]
 
 (* TODO: move *)
-let bs_ctx_to_ast_formatter (ctx : bs_ctx) : Print.Ast.ast_formatter =
-  Print.Ast.decls_and_fun_decl_to_ast_formatter ctx.type_context.llbc_type_decls
-    ctx.fun_context.llbc_fun_decls ctx.global_context.llbc_global_decls
-    ctx.trait_decls_ctx ctx.trait_impls_ctx ctx.fun_decl
-
-let bs_ctx_to_ctx_formatter (ctx : bs_ctx) : Print.Contexts.ctx_formatter =
-  let rvar_to_string = Print.Types.region_var_id_to_string in
-  let r_to_string = Print.Types.region_id_to_string in
-  let type_var_id_to_string = Print.Types.type_var_id_to_string in
-  let var_id_to_string = Print.Expressions.var_id_to_string in
-  let ast_fmt = bs_ctx_to_ast_formatter ctx in
+let bs_ctx_to_fmt_env (ctx : bs_ctx) : Print.fmt_env =
+  let type_decls = ctx.type_context.llbc_type_decls in
+  let fun_decls = ctx.fun_context.llbc_fun_decls in
+  let global_decls = ctx.global_context.llbc_global_decls in
+  let trait_decls = ctx.trait_decls_ctx in
+  let trait_impls = ctx.trait_impls_ctx in
+  let generics = ctx.fun_decl.signature.generics in
+  let preds = ctx.fun_decl.signature.preds in
   {
-    Print.Values.rvar_to_string;
-    r_to_string;
-    type_var_id_to_string;
-    type_decl_id_to_string = ast_fmt.type_decl_id_to_string;
-    const_generic_var_id_to_string = ast_fmt.const_generic_var_id_to_string;
-    global_decl_id_to_string = ast_fmt.global_decl_id_to_string;
-    adt_variant_to_string = ast_fmt.adt_variant_to_string;
-    var_id_to_string;
-    adt_field_names = ast_fmt.adt_field_names;
-    trait_decl_id_to_string = ast_fmt.trait_decl_id_to_string;
-    trait_impl_id_to_string = ast_fmt.trait_impl_id_to_string;
-    trait_clause_id_to_string = ast_fmt.trait_clause_id_to_string;
+    type_decls;
+    fun_decls;
+    global_decls;
+    trait_decls;
+    trait_impls;
+    generics;
+    preds;
+    locals = [];
   }
 
-let bs_ctx_to_pp_ast_formatter (ctx : bs_ctx) : PrintPure.ast_formatter =
-  let generics = ctx.fun_decl.signature.generics in
+let bs_ctx_to_pure_fmt_env (ctx : bs_ctx) : PrintPure.fmt_env =
   let type_decls = ctx.type_context.llbc_type_decls in
   let fun_decls = ctx.fun_context.llbc_fun_decls in
   let global_decls = ctx.global_context.llbc_global_decls in
-  PrintPure.mk_ast_formatter type_decls fun_decls global_decls
-    ctx.trait_decls_ctx ctx.trait_impls_ctx generics.types
-    generics.const_generics
+  let trait_decls = ctx.trait_decls_ctx in
+  let trait_impls = ctx.trait_impls_ctx in
+  let generics = ctx.sg.generics in
+  {
+    type_decls;
+    fun_decls;
+    global_decls;
+    trait_decls;
+    trait_impls;
+    generics;
+    locals = [];
+  }
 
-let ctx_egeneric_args_to_string (ctx : bs_ctx) (args : T.egeneric_args) : string
-    =
-  let fmt = bs_ctx_to_ctx_formatter ctx in
-  let fmt = Print.PC.ctx_to_etype_formatter fmt in
-  Print.PT.egeneric_args_to_string fmt args
+let ctx_generic_args_to_string (ctx : bs_ctx) (args : T.generic_args) : string =
+  let env = bs_ctx_to_fmt_env ctx in
+  Print.Types.generic_args_to_string env args
+
+let name_to_string (ctx : bs_ctx) =
+  Print.Types.name_to_string (bs_ctx_to_fmt_env ctx)
 
 let symbolic_value_to_string (ctx : bs_ctx) (sv : V.symbolic_value) : string =
-  let fmt = bs_ctx_to_ctx_formatter ctx in
-  let fmt = Print.PC.ctx_to_rtype_formatter fmt in
-  Print.PV.symbolic_value_to_string fmt sv
+  let env = bs_ctx_to_fmt_env ctx in
+  Print.Values.symbolic_value_to_string env sv
 
 let typed_value_to_string (ctx : bs_ctx) (v : V.typed_value) : string =
-  let fmt = bs_ctx_to_ctx_formatter ctx in
-  Print.PV.typed_value_to_string fmt v
+  let env = bs_ctx_to_fmt_env ctx in
+  Print.Values.typed_value_to_string env v
 
-let ty_to_string (ctx : bs_ctx) (ty : ty) : string =
-  let fmt = bs_ctx_to_pp_ast_formatter ctx in
-  let fmt = PrintPure.ast_to_type_formatter fmt in
-  PrintPure.ty_to_string fmt false ty
+let pure_ty_to_string (ctx : bs_ctx) (ty : ty) : string =
+  let env = bs_ctx_to_pure_fmt_env ctx in
+  PrintPure.ty_to_string env false ty
 
-let rty_to_string (ctx : bs_ctx) (ty : T.rty) : string =
-  let fmt = bs_ctx_to_ctx_formatter ctx in
-  let fmt = Print.PC.ctx_to_rtype_formatter fmt in
-  Print.PT.rty_to_string fmt ty
+let ty_to_string (ctx : bs_ctx) (ty : T.ty) : string =
+  let env = bs_ctx_to_fmt_env ctx in
+  Print.Types.ty_to_string env ty
 
-let type_decl_to_string (ctx : bs_ctx) (def : type_decl) : string =
-  let type_decls = ctx.type_context.llbc_type_decls in
-  let global_decls = ctx.global_context.llbc_global_decls in
-  let fmt =
-    PrintPure.mk_type_formatter type_decls global_decls ctx.trait_decls_ctx
-      ctx.trait_impls_ctx def.generics.types def.generics.const_generics
-  in
-  PrintPure.type_decl_to_string fmt def
+let type_decl_to_string (ctx : bs_ctx) (def : T.type_decl) : string =
+  let env = bs_ctx_to_fmt_env ctx in
+  Print.Types.type_decl_to_string env def
+
+let pure_type_decl_to_string (ctx : bs_ctx) (def : type_decl) : string =
+  let env = bs_ctx_to_pure_fmt_env ctx in
+  PrintPure.type_decl_to_string env def
 
 let texpression_to_string (ctx : bs_ctx) (e : texpression) : string =
-  let fmt = bs_ctx_to_pp_ast_formatter ctx in
-  PrintPure.texpression_to_string fmt false "" "  " e
+  let env = bs_ctx_to_pure_fmt_env ctx in
+  PrintPure.texpression_to_string env false "" "  " e
 
 let fun_sig_to_string (ctx : bs_ctx) (sg : fun_sig) : string =
-  let type_params = sg.generics.types in
-  let cg_params = sg.generics.const_generics in
-  let type_decls = ctx.type_context.llbc_type_decls in
-  let fun_decls = ctx.fun_context.llbc_fun_decls in
-  let global_decls = ctx.global_context.llbc_global_decls in
-  let fmt =
-    PrintPure.mk_ast_formatter type_decls fun_decls global_decls
-      ctx.trait_decls_ctx ctx.trait_impls_ctx type_params cg_params
-  in
-  PrintPure.fun_sig_to_string fmt sg
+  let env = bs_ctx_to_pure_fmt_env ctx in
+  PrintPure.fun_sig_to_string env sg
 
 let fun_decl_to_string (ctx : bs_ctx) (def : Pure.fun_decl) : string =
-  let generics = def.signature.generics in
-  let type_params = generics.types in
-  let cg_params = generics.const_generics in
-  let type_decls = ctx.type_context.llbc_type_decls in
-  let fun_decls = ctx.fun_context.llbc_fun_decls in
-  let global_decls = ctx.global_context.llbc_global_decls in
-  let fmt =
-    PrintPure.mk_ast_formatter type_decls fun_decls global_decls
-      ctx.trait_decls_ctx ctx.trait_impls_ctx type_params cg_params
-  in
-  PrintPure.fun_decl_to_string fmt def
+  let env = bs_ctx_to_pure_fmt_env ctx in
+  PrintPure.fun_decl_to_string env def
 
 let typed_pattern_to_string (ctx : bs_ctx) (p : Pure.typed_pattern) : string =
-  let fmt = bs_ctx_to_pp_ast_formatter ctx in
-  PrintPure.typed_pattern_to_string fmt p
+  let env = bs_ctx_to_pure_fmt_env ctx in
+  PrintPure.typed_pattern_to_string env p
 
 (* TODO: move *)
 let abs_to_string (ctx : bs_ctx) (abs : V.abs) : string =
-  let fmt = bs_ctx_to_ast_formatter ctx in
-  let fmt = Print.Contexts.ast_to_value_formatter fmt in
+  let env = bs_ctx_to_fmt_env ctx in
   let verbose = false in
   let indent = "" in
   let indent_incr = "  " in
-  Print.Values.abs_to_string fmt verbose indent indent_incr abs
+  Print.Values.abs_to_string env verbose indent indent_incr abs
 
 let get_instantiated_fun_sig (fun_id : A.fun_id)
     (back_id : T.RegionGroupId.id option) (generics : generic_args)
@@ -343,13 +324,13 @@ let bs_ctx_lookup_llbc_fun_decl (id : A.FunDeclId.id) (ctx : bs_ctx) :
 (* TODO: move *)
 let bs_ctx_lookup_local_function_sig (def_id : A.FunDeclId.id)
     (back_id : T.RegionGroupId.id option) (ctx : bs_ctx) : fun_sig =
-  let id = (E.Regular def_id, back_id) in
+  let id = (E.FRegular def_id, back_id) in
   (RegularFunIdNotLoopMap.find id ctx.fun_context.fun_sigs).sg
 
 (* Some generic translation functions (we need to translate different "flavours"
-   of types: sty, forward types, backward types, etc.) *)
-let rec translate_generic_args (translate_ty : 'r T.ty -> ty)
-    (generics : 'r T.generic_args) : generic_args =
+   of types: forward types, backward types, etc.) *)
+let rec translate_generic_args (translate_ty : T.ty -> ty)
+    (generics : T.generic_args) : generic_args =
   (* We ignore the regions: if they didn't cause trouble for the symbolic execution,
      then everything's fine *)
   let types = List.map translate_ty generics.types in
@@ -359,7 +340,7 @@ let rec translate_generic_args (translate_ty : 'r T.ty -> ty)
   in
   { types; const_generics; trait_refs }
 
-and translate_trait_ref (translate_ty : 'r T.ty -> ty) (tr : 'r T.trait_ref) :
+and translate_trait_ref (translate_ty : T.ty -> ty) (tr : T.trait_ref) :
     trait_ref =
   let trait_id = translate_trait_instance_id translate_ty tr.trait_id in
   let generics = translate_generic_args translate_ty tr.generics in
@@ -368,13 +349,13 @@ and translate_trait_ref (translate_ty : 'r T.ty -> ty) (tr : 'r T.trait_ref) :
   in
   { trait_id; generics; trait_decl_ref }
 
-and translate_trait_decl_ref (translate_ty : 'r T.ty -> ty)
-    (tr : 'r T.trait_decl_ref) : trait_decl_ref =
+and translate_trait_decl_ref (translate_ty : T.ty -> ty) (tr : T.trait_decl_ref)
+    : trait_decl_ref =
   let decl_generics = translate_generic_args translate_ty tr.decl_generics in
   { trait_decl_id = tr.trait_decl_id; decl_generics }
 
-and translate_trait_instance_id (translate_ty : 'r T.ty -> ty)
-    (id : 'r T.trait_instance_id) : trait_instance_id =
+and translate_trait_instance_id (translate_ty : T.ty -> ty)
+    (id : T.trait_instance_id) : trait_instance_id =
   let translate_trait_instance_id = translate_trait_instance_id translate_ty in
   match id with
   | T.Self -> Self
@@ -393,19 +374,20 @@ and translate_trait_instance_id (translate_ty : 'r T.ty -> ty)
   | FnPointer _ -> raise (Failure "TODO")
   | UnknownTrait s -> raise (Failure ("Unknown trait found: " ^ s))
 
-let rec translate_sty (ty : T.sty) : ty =
+(** Translate a signature type - TODO: factor out the different translation functions *)
+let rec translate_sty (ty : T.ty) : ty =
   let translate = translate_sty in
   match ty with
-  | T.Adt (type_id, generics) -> (
+  | T.TAdt (type_id, generics) -> (
       let generics = translate_sgeneric_args generics in
       match type_id with
-      | T.AdtId adt_id -> Adt (AdtId adt_id, generics)
-      | T.Tuple ->
+      | T.TAdtId adt_id -> TAdt (TAdtId adt_id, generics)
+      | T.TTuple ->
           assert (generics.const_generics = []);
           mk_simpl_tuple_ty generics.types
-      | T.Assumed aty -> (
+      | T.TAssumed aty -> (
           match aty with
-          | T.Box -> (
+          | T.TBox -> (
               (* Eliminate the boxes *)
               match generics.types with
               | [ ty ] -> ty
@@ -414,40 +396,40 @@ let rec translate_sty (ty : T.sty) : ty =
                     (Failure
                        "Box/vec/option type with incorrect number of arguments")
               )
-          | T.Array -> Adt (Assumed Array, generics)
-          | T.Slice -> Adt (Assumed Slice, generics)
-          | T.Str -> Adt (Assumed Str, generics)))
-  | TypeVar vid -> TypeVar vid
-  | Literal ty -> Literal ty
-  | Never -> raise (Failure "Unreachable")
-  | Ref (_, rty, _) -> translate rty
-  | RawPtr (ty, rkind) ->
-      let mut = match rkind with Mut -> Mut | Shared -> Const in
+          | T.TArray -> TAdt (TAssumed TArray, generics)
+          | T.TSlice -> TAdt (TAssumed TSlice, generics)
+          | T.TStr -> TAdt (TAssumed TStr, generics)))
+  | TVar vid -> TVar vid
+  | TLiteral ty -> TLiteral ty
+  | TNever -> raise (Failure "Unreachable")
+  | TRef (_, rty, _) -> translate rty
+  | TRawPtr (ty, rkind) ->
+      let mut = match rkind with RMut -> Mut | RShared -> Const in
       let ty = translate ty in
       let generics = { types = [ ty ]; const_generics = []; trait_refs = [] } in
-      Adt (Assumed (RawPtr mut), generics)
-  | TraitType (trait_ref, generics, type_name) ->
+      TAdt (TAssumed (TRawPtr mut), generics)
+  | TTraitType (trait_ref, generics, type_name) ->
       let trait_ref = translate_strait_ref trait_ref in
       let generics = translate_sgeneric_args generics in
-      TraitType (trait_ref, generics, type_name)
-  | Arrow _ -> raise (Failure "TODO")
+      TTraitType (trait_ref, generics, type_name)
+  | TArrow _ -> raise (Failure "TODO")
 
-and translate_sgeneric_args (generics : T.sgeneric_args) : generic_args =
+and translate_sgeneric_args (generics : T.generic_args) : generic_args =
   translate_generic_args translate_sty generics
 
-and translate_strait_ref (tr : T.strait_ref) : trait_ref =
+and translate_strait_ref (tr : T.trait_ref) : trait_ref =
   translate_trait_ref translate_sty tr
 
-and translate_strait_instance_id (id : T.strait_instance_id) : trait_instance_id
+and translate_strait_instance_id (id : T.trait_instance_id) : trait_instance_id
     =
   translate_trait_instance_id translate_sty id
 
 let translate_trait_clause (clause : T.trait_clause) : trait_clause =
-  let { T.clause_id; meta = _; trait_id; generics } = clause in
-  let generics = translate_sgeneric_args generics in
+  let { T.clause_id; meta = _; trait_id; clause_generics } = clause in
+  let generics = translate_sgeneric_args clause_generics in
   { clause_id; trait_id; generics }
 
-let translate_strait_type_constraint (ttc : T.strait_type_constraint) :
+let translate_strait_type_constraint (ttc : T.trait_type_constraint) :
     trait_type_constraint =
   let { T.trait_ref; generics; type_name; ty } = ttc in
   let trait_ref = translate_strait_ref trait_ref in
@@ -482,21 +464,30 @@ let translate_variant (v : T.variant) : variant =
 let translate_variants (vl : T.variant list) : variant list =
   List.map translate_variant vl
 
-(** Translate a type def kind to IM *)
+(** Translate a type def kind from LLBC *)
 let translate_type_decl_kind (kind : T.type_decl_kind) : type_decl_kind =
   match kind with
   | T.Struct fields -> Struct (translate_fields fields)
   | T.Enum variants -> Enum (translate_variants variants)
   | T.Opaque -> Opaque
 
-(** Translate a type definition from IM 
+(** Translate a type definition from LLBC
 
-    TODO: this is not symbolic to pure but IM to pure. Still, I don't see the
-    point of moving this definition for now.
+    Remark: this is not symbolic to pure but LLBC to pure. Still,
+    I don't see the point of moving this definition for now.
  *)
-let translate_type_decl (def : T.type_decl) : type_decl =
+let translate_type_decl (ctx : Contexts.decls_ctx) (def : T.type_decl) :
+    type_decl =
+  log#ldebug
+    (lazy
+      (let ctx = Print.Contexts.decls_ctx_to_fmt_env ctx in
+       "translate_type_decl:\n\n"
+       ^ Print.Types.type_decl_to_string ctx def
+       ^ "\n"));
+  let env = Print.Contexts.decls_ctx_to_fmt_env ctx in
   let def_id = def.T.def_id in
-  let name = def.name in
+  let llbc_name = def.name in
+  let name = Print.Types.name_to_string env def.name in
   let { T.regions; types; const_generics; trait_clauses } = def.generics in
   (* Can't translate types with regions for now *)
   assert (regions = []);
@@ -504,43 +495,60 @@ let translate_type_decl (def : T.type_decl) : type_decl =
   let generics = { types; const_generics; trait_clauses } in
   let kind = translate_type_decl_kind def.T.kind in
   let preds = translate_predicates def.preds in
-  { def_id; name; generics; kind; preds }
+  let is_local = def.is_local in
+  let meta = def.meta in
+  {
+    def_id;
+    is_local;
+    llbc_name;
+    name;
+    meta;
+    generics;
+    llbc_generics = def.generics;
+    kind;
+    preds;
+  }
 
 let translate_type_id (id : T.type_id) : type_id =
   match id with
-  | AdtId adt_id -> AdtId adt_id
-  | T.Assumed aty ->
+  | TAdtId adt_id -> TAdtId adt_id
+  | TAssumed aty ->
       let aty =
         match aty with
-        | T.Array -> Array
-        | T.Slice -> Slice
-        | T.Str -> Str
-        | T.Box ->
+        | T.TArray -> TArray
+        | T.TSlice -> TSlice
+        | T.TStr -> TStr
+        | T.TBox ->
             (* Boxes have to be eliminated: this type id shouldn't
                be translated *)
             raise (Failure "Unreachable")
       in
-      Assumed aty
-  | T.Tuple -> Tuple
+      TAssumed aty
+  | TTuple -> TTuple
 
 (** Translate a type, seen as an input/output of a forward function
-    (preserve all borrows, etc.)
+    (preserve all borrows, etc.).
+
+    Remark: it doesn't matter whether the types has regions or erased regions
+    (both cases happen, actually).
+
+    TODO: factor out the various translation functions.
 *)
-let rec translate_fwd_ty (type_infos : TA.type_infos) (ty : 'r T.ty) : ty =
+let rec translate_fwd_ty (type_infos : type_infos) (ty : T.ty) : ty =
   let translate = translate_fwd_ty type_infos in
   match ty with
-  | T.Adt (type_id, generics) -> (
+  | T.TAdt (type_id, generics) -> (
       let t_generics = translate_fwd_generic_args type_infos generics in
       (* Eliminate boxes and simplify tuples *)
       match type_id with
-      | AdtId _ | T.Assumed (T.Array | T.Slice | T.Str) ->
+      | TAdtId _ | TAssumed (TArray | TSlice | TStr) ->
           let type_id = translate_type_id type_id in
-          Adt (type_id, t_generics)
-      | Tuple ->
+          TAdt (type_id, t_generics)
+      | TTuple ->
           (* Note that if there is exactly one type, [mk_simpl_tuple_ty] is the
              identity *)
           mk_simpl_tuple_ty t_generics.types
-      | T.Assumed T.Box -> (
+      | TAssumed TBox -> (
           (* We eliminate boxes *)
           (* No general parametricity for now *)
           assert (
@@ -555,41 +563,41 @@ let rec translate_fwd_ty (type_infos : TA.type_infos) (ty : 'r T.ty) : ty =
                 (Failure
                    "Unreachable: box/vec/option receives exactly one type \
                     parameter")))
-  | TypeVar vid -> TypeVar vid
-  | Never -> raise (Failure "Unreachable")
-  | Literal lty -> Literal lty
-  | Ref (_, rty, _) -> translate rty
-  | RawPtr (ty, rkind) ->
-      let mut = match rkind with Mut -> Mut | Shared -> Const in
+  | TVar vid -> TVar vid
+  | TNever -> raise (Failure "Unreachable")
+  | TLiteral lty -> TLiteral lty
+  | TRef (_, rty, _) -> translate rty
+  | TRawPtr (ty, rkind) ->
+      let mut = match rkind with RMut -> Mut | RShared -> Const in
       let ty = translate ty in
       let generics = { types = [ ty ]; const_generics = []; trait_refs = [] } in
-      Adt (Assumed (RawPtr mut), generics)
-  | TraitType (trait_ref, generics, type_name) ->
+      TAdt (TAssumed (TRawPtr mut), generics)
+  | TTraitType (trait_ref, generics, type_name) ->
       let trait_ref = translate_fwd_trait_ref type_infos trait_ref in
       let generics = translate_fwd_generic_args type_infos generics in
-      TraitType (trait_ref, generics, type_name)
-  | Arrow _ -> raise (Failure "TODO")
+      TTraitType (trait_ref, generics, type_name)
+  | TArrow _ -> raise (Failure "TODO")
 
-and translate_fwd_generic_args (type_infos : TA.type_infos)
-    (generics : 'r T.generic_args) : generic_args =
+and translate_fwd_generic_args (type_infos : type_infos)
+    (generics : T.generic_args) : generic_args =
   translate_generic_args (translate_fwd_ty type_infos) generics
 
-and translate_fwd_trait_ref (type_infos : TA.type_infos) (tr : 'r T.trait_ref) :
+and translate_fwd_trait_ref (type_infos : type_infos) (tr : T.trait_ref) :
     trait_ref =
   translate_trait_ref (translate_fwd_ty type_infos) tr
 
-and translate_fwd_trait_instance_id (type_infos : TA.type_infos)
-    (id : 'r T.trait_instance_id) : trait_instance_id =
+and translate_fwd_trait_instance_id (type_infos : type_infos)
+    (id : T.trait_instance_id) : trait_instance_id =
   translate_trait_instance_id (translate_fwd_ty type_infos) id
 
 (** Simply calls [translate_fwd_ty] *)
-let ctx_translate_fwd_ty (ctx : bs_ctx) (ty : 'r T.ty) : ty =
+let ctx_translate_fwd_ty (ctx : bs_ctx) (ty : T.ty) : ty =
   let type_infos = ctx.type_context.type_infos in
   translate_fwd_ty type_infos ty
 
 (** Simply calls [translate_fwd_generic_args] *)
-let ctx_translate_fwd_generic_args (ctx : bs_ctx) (generics : 'r T.generic_args)
-    : generic_args =
+let ctx_translate_fwd_generic_args (ctx : bs_ctx) (generics : T.generic_args) :
+    generic_args =
   let type_infos = ctx.type_context.type_infos in
   translate_fwd_generic_args type_infos generics
 
@@ -599,21 +607,22 @@ let ctx_translate_fwd_generic_args (ctx : bs_ctx) (generics : 'r T.generic_args)
     
     [inside_mut]: are we inside a mutable borrow?
  *)
-let rec translate_back_ty (type_infos : TA.type_infos)
-    (keep_region : 'r -> bool) (inside_mut : bool) (ty : 'r T.ty) : ty option =
+let rec translate_back_ty (type_infos : type_infos)
+    (keep_region : T.region -> bool) (inside_mut : bool) (ty : T.ty) : ty option
+    =
   let translate = translate_back_ty type_infos keep_region inside_mut in
   (* A small helper for "leave" types *)
   let wrap ty = if inside_mut then Some ty else None in
   match ty with
-  | T.Adt (type_id, generics) -> (
+  | T.TAdt (type_id, generics) -> (
       match type_id with
-      | T.AdtId _ | Assumed (T.Array | T.Slice | T.Str) ->
+      | TAdtId _ | TAssumed (TArray | TSlice | TStr) ->
           let type_id = translate_type_id type_id in
           if inside_mut then
             (* We do not want to filter anything, so we translate the generics
                as "forward" types *)
             let generics = translate_fwd_generic_args type_infos generics in
-            Some (Adt (type_id, generics))
+            Some (TAdt (type_id, generics))
           else
             (* If not inside a mutable reference: check if at least one
                of the generics contains a mutable reference (i.e., is not
@@ -624,9 +633,9 @@ let rec translate_back_ty (type_infos : TA.type_infos)
             let types = List.filter_map translate generics.types in
             if types <> [] then
               let generics = translate_fwd_generic_args type_infos generics in
-              Some (Adt (type_id, generics))
+              Some (TAdt (type_id, generics))
             else None
-      | Assumed T.Box -> (
+      | TAssumed TBox -> (
           (* Don't accept ADTs (which are not tuples) with borrows for now *)
           assert (not (TypesUtils.ty_has_borrows type_infos ty));
           (* Eliminate the box *)
@@ -636,7 +645,7 @@ let rec translate_back_ty (type_infos : TA.type_infos)
               raise
                 (Failure "Unreachable: boxes receive exactly one type parameter")
           )
-      | T.Tuple -> (
+      | TTuple -> (
           (* Tuples can contain borrows (which we eliminate) *)
           let tys_t = List.filter_map translate generics.types in
           match tys_t with
@@ -645,35 +654,35 @@ let rec translate_back_ty (type_infos : TA.type_infos)
               (* Note that if there is exactly one type, [mk_simpl_tuple_ty]
                * is the identity *)
               Some (mk_simpl_tuple_ty tys_t)))
-  | TypeVar vid -> wrap (TypeVar vid)
-  | Never -> raise (Failure "Unreachable")
-  | Literal lty -> wrap (Literal lty)
-  | Ref (r, rty, rkind) -> (
+  | TVar vid -> wrap (TVar vid)
+  | TNever -> raise (Failure "Unreachable")
+  | TLiteral lty -> wrap (TLiteral lty)
+  | TRef (r, rty, rkind) -> (
       match rkind with
-      | T.Shared ->
+      | RShared ->
           (* Ignore shared references, unless we are below a mutable borrow *)
           if inside_mut then translate rty else None
-      | T.Mut ->
+      | RMut ->
           (* Dive in, remembering the fact that we are inside a mutable borrow *)
           let inside_mut = true in
           if keep_region r then
             translate_back_ty type_infos keep_region inside_mut rty
           else None)
-  | RawPtr _ ->
+  | TRawPtr _ ->
       (* TODO: not sure what to do here *)
       None
-  | TraitType (trait_ref, generics, type_name) ->
+  | TTraitType (trait_ref, generics, type_name) ->
       assert (generics.regions = []);
       (* Translate the trait ref and the generics as "forward" generics -
          we do not want to filter any type *)
       let trait_ref = translate_fwd_trait_ref type_infos trait_ref in
       let generics = translate_fwd_generic_args type_infos generics in
-      Some (TraitType (trait_ref, generics, type_name))
-  | Arrow _ -> raise (Failure "TODO")
+      Some (TTraitType (trait_ref, generics, type_name))
+  | TArrow _ -> raise (Failure "TODO")
 
 (** Simply calls [translate_back_ty] *)
 let ctx_translate_back_ty (ctx : bs_ctx) (keep_region : 'r -> bool)
-    (inside_mut : bool) (ty : 'r T.ty) : ty option =
+    (inside_mut : bool) (ty : T.ty) : ty option =
   let type_infos = ctx.type_context.type_infos in
   translate_back_ty type_infos keep_region inside_mut ty
 
@@ -682,7 +691,7 @@ let mk_type_check_ctx (ctx : bs_ctx) : PureTypeCheck.tc_ctx =
     T.ConstGenericVarId.Map.of_list
       (List.map
          (fun (cg : T.const_generic_var) ->
-           (cg.index, ctx_translate_fwd_ty ctx (T.Literal cg.ty)))
+           (cg.index, ctx_translate_fwd_ty ctx (T.TLiteral cg.ty)))
          ctx.sg.generics.const_generics)
   in
   let env = VarId.Map.empty in
@@ -803,11 +812,11 @@ let mk_fuel_input_as_list (ctx : bs_ctx) (info : fun_effect_info) :
   if function_uses_fuel info then [ mk_fuel_texpression ctx.fuel ] else []
 
 (** Small utility. *)
-let get_fun_effect_info (fun_infos : FA.fun_info A.FunDeclId.Map.t)
+let get_fun_effect_info (fun_infos : fun_info A.FunDeclId.Map.t)
     (fun_id : A.fun_id_or_trait_method_ref) (lid : V.LoopId.id option)
     (gid : T.RegionGroupId.id option) : fun_effect_info =
   match fun_id with
-  | TraitMethod (_, _, fid) | FunId (Regular fid) ->
+  | TraitMethod (_, _, fid) | FunId (FRegular fid) ->
       let info = A.FunDeclId.Map.find fid fun_infos in
       let stateful_group = info.stateful in
       let stateful =
@@ -820,7 +829,7 @@ let get_fun_effect_info (fun_infos : FA.fun_info A.FunDeclId.Map.t)
         can_diverge = info.can_diverge;
         is_rec = info.is_rec || Option.is_some lid;
       }
-  | FunId (Assumed aid) ->
+  | FunId (FAssumed aid) ->
       assert (lid = None);
       {
         can_fail = Assumed.assumed_fun_can_fail aid;
@@ -844,11 +853,14 @@ let translate_fun_sig (decls_ctx : C.decls_ctx) (fun_id : A.fun_id)
   let fun_infos = decls_ctx.fun_ctx.fun_infos in
   let type_infos = decls_ctx.type_ctx.type_infos in
   (* Retrieve the list of parent backward functions *)
+  let regions_hierarchy =
+    FunIdMap.find fun_id decls_ctx.fun_ctx.regions_hierarchies
+  in
   let gid, parents =
     match bid with
     | None -> (None, T.RegionGroupId.Set.empty)
     | Some bid ->
-        let parents = list_ancestor_region_groups sg bid in
+        let parents = list_ancestor_region_groups regions_hierarchy bid in
         (Some bid, parents)
   in
   (* Is the function stateful, and can it fail? *)
@@ -861,21 +873,21 @@ let translate_fun_sig (decls_ctx : C.decls_ctx) (fun_id : A.fun_id)
   (* Create the context *)
   let ctx =
     let region_groups =
-      List.map (fun (g : T.region_var_group) -> g.id) sg.regions_hierarchy
+      List.map (fun (g : T.region_group) -> g.id) regions_hierarchy
     in
     let ctx =
       InterpreterUtils.initialize_eval_context decls_ctx region_groups
         sg.generics.types sg.generics.const_generics
     in
     (* Compute the normalization map for the *sty* types and add it to the context *)
-    AssociatedTypes.ctx_add_norm_trait_stypes_from_preds ctx
+    AssociatedTypes.ctx_add_norm_trait_types_from_preds ctx
       sg.preds.trait_type_constraints
   in
 
   (* Normalize the signature *)
   let sg =
     let ({ A.inputs; output; _ } : A.fun_sig) = sg in
-    let norm = AssociatedTypes.ctx_normalize_sty ctx in
+    let norm = AssociatedTypes.ctx_normalize_ty ctx in
     let inputs = List.map norm inputs in
     let output = norm output in
     { sg with A.inputs; output }
@@ -893,14 +905,14 @@ let translate_fun_sig (decls_ctx : C.decls_ctx) (fun_id : A.fun_id)
    * so just check that there aren't parent regions *)
   assert (T.RegionGroupId.Set.is_empty parents);
   (* Small helper to translate types for backward functions *)
-  let translate_back_ty_for_gid (gid : T.RegionGroupId.id) : T.sty -> ty option
-      =
-    let rg = T.RegionGroupId.nth sg.regions_hierarchy gid in
-    let regions = T.RegionVarId.Set.of_list rg.regions in
+  let translate_back_ty_for_gid (gid : T.RegionGroupId.id) : T.ty -> ty option =
+    let rg = T.RegionGroupId.nth regions_hierarchy gid in
+    let regions = T.RegionId.Set.of_list rg.regions in
     let keep_region r =
       match r with
-      | T.Static -> raise Unimplemented
-      | T.Var r -> T.RegionVarId.Set.mem r regions
+      | T.RStatic -> raise Unimplemented
+      | T.RErased -> raise (Failure "Unexpected erased region")
+      | T.RVar r -> T.RegionId.Set.mem r regions
     in
     let inside_mut = false in
     translate_back_ty type_infos keep_region inside_mut
@@ -1026,8 +1038,18 @@ let translate_fun_sig (decls_ctx : C.decls_ctx) (fun_id : A.fun_id)
       effect_info;
     }
   in
-  let preds = translate_predicates sg.A.preds in
-  let sg = { generics; preds; inputs; output; doutputs; info } in
+  let preds = translate_predicates sg.preds in
+  let sg =
+    {
+      generics;
+      llbc_generics = sg.generics;
+      preds;
+      inputs;
+      output;
+      doutputs;
+      info;
+    }
+  in
   { sg; output_names }
 
 let bs_ctx_fresh_state_var (ctx : bs_ctx) : bs_ctx * typed_pattern =
@@ -1042,7 +1064,7 @@ let bs_ctx_fresh_state_var (ctx : bs_ctx) : bs_ctx * typed_pattern =
   (* Return *)
   (ctx, state_pat)
 
-let fresh_var_llbc_ty (basename : string option) (ty : 'r T.ty) (ctx : bs_ctx) :
+let fresh_var_llbc_ty (basename : string option) (ty : T.ty) (ctx : bs_ctx) :
     bs_ctx * var =
   (* Generate the fresh variable *)
   let id, var_counter = VarId.fresh ctx.var_counter in
@@ -1106,7 +1128,7 @@ let lookup_var_for_symbolic_value (sv : V.symbolic_value) (ctx : bs_ctx) : var =
 (** Peel boxes as long as the value is of the form [Box<T>] *)
 let rec unbox_typed_value (v : V.typed_value) : V.typed_value =
   match (v.value, v.ty) with
-  | V.Adt av, T.Adt (T.Assumed T.Box, _) -> (
+  | V.VAdt av, T.TAdt (T.TAssumed T.TBox, _) -> (
       match av.field_values with
       | [ bv ] -> unbox_typed_value bv
       | _ -> raise (Failure "Unreachable"))
@@ -1145,13 +1167,13 @@ let rec typed_value_to_texpression (ctx : bs_ctx) (ectx : C.eval_ctx)
   (* Translate the value *)
   let value =
     match v.value with
-    | V.Literal cv -> { e = Const cv; ty }
-    | Adt av -> (
+    | VLiteral cv -> { e = Const cv; ty }
+    | VAdt av -> (
         let variant_id = av.variant_id in
         let field_values = List.map translate av.field_values in
         (* Eliminate the tuple wrapper if it is a tuple with exactly one field *)
         match v.ty with
-        | T.Adt (T.Tuple, _) ->
+        | TAdt (TTuple, _) ->
             assert (variant_id = None);
             mk_simpl_tuple_texpression field_values
         | _ ->
@@ -1169,27 +1191,27 @@ let rec typed_value_to_texpression (ctx : bs_ctx) (ectx : C.eval_ctx)
             let cons = { e = cons_e; ty = cons_ty } in
             (* Apply the constructor *)
             mk_apps cons field_values)
-    | Bottom -> raise (Failure "Unreachable")
-    | Loan lc -> (
+    | VBottom -> raise (Failure "Unreachable")
+    | VLoan lc -> (
         match lc with
-        | SharedLoan (_, v) -> translate v
-        | MutLoan _ -> raise (Failure "Unreachable"))
-    | Borrow bc -> (
+        | VSharedLoan (_, v) -> translate v
+        | VMutLoan _ -> raise (Failure "Unreachable"))
+    | VBorrow bc -> (
         match bc with
-        | V.SharedBorrow bid ->
+        | VSharedBorrow bid ->
             (* Lookup the shared value in the context, and continue *)
             let sv = InterpreterBorrowsCore.lookup_shared_value ectx bid in
             translate sv
-        | V.ReservedMutBorrow bid ->
+        | VReservedMutBorrow bid ->
             (* Same as for shared borrows. However, note that we use reserved borrows
              * only in *meta-data*: a value *actually used* in the translation can't come
              * from an unpromoted reserved borrow *)
             let sv = InterpreterBorrowsCore.lookup_shared_value ectx bid in
             translate sv
-        | V.MutBorrow (_, v) ->
+        | VMutBorrow (_, v) ->
             (* Borrows are the identity in the extraction *)
             translate v)
-    | Symbolic sv -> symbolic_value_to_texpression ctx sv
+    | VSymbolic sv -> symbolic_value_to_texpression ctx sv
   in
   (* Debugging *)
   log#ldebug
@@ -1229,10 +1251,10 @@ let rec typed_avalue_to_consumed (ctx : bs_ctx) (ectx : C.eval_ctx)
         (* For now, only tuples can contain borrows *)
         let adt_id, _ = TypesUtils.ty_as_adt av.ty in
         match adt_id with
-        | T.AdtId _ | T.Assumed (T.Box | T.Array | T.Slice | T.Str) ->
+        | TAdtId _ | TAssumed (TBox | TArray | TSlice | TStr) ->
             assert (field_values = []);
             None
-        | T.Tuple ->
+        | TTuple ->
             (* Return *)
             if field_values = [] then None
             else
@@ -1374,10 +1396,10 @@ let rec typed_avalue_to_given_back (mp : mplace option) (av : V.typed_avalue)
          * vector value upon visiting the "abstraction borrow" node *)
         let adt_id, _ = TypesUtils.ty_as_adt av.ty in
         match adt_id with
-        | T.AdtId _ | T.Assumed (T.Box | T.Array | T.Slice | T.Str) ->
+        | TAdtId _ | TAssumed (TBox | TArray | TSlice | TStr) ->
             assert (field_values = []);
             (ctx, None)
-        | T.Tuple ->
+        | TTuple ->
             (* Return *)
             let variant_id = adt_v.variant_id in
             assert (variant_id = None);
@@ -1488,11 +1510,11 @@ let get_abs_ancestors (ctx : bs_ctx) (abs : V.abs) (call_id : V.FunCallId.id) :
   (call_info.forward, abs_ancestors)
 
 (** Add meta-information to an expression *)
-let mk_meta_symbolic_assignments (vars : var list) (values : texpression list)
+let mk_emeta_symbolic_assignments (vars : var list) (values : texpression list)
     (e : texpression) : texpression =
   let var_values = List.combine vars values in
   List.fold_right
-    (fun (var, arg) e -> mk_meta (SymbolicAssignment (var_get_id var, arg)) e)
+    (fun (var, arg) e -> mk_emeta (SymbolicAssignment (var_get_id var, arg)) e)
     var_values e
 
 let rec translate_expression (e : S.expression) (ctx : bs_ctx) : texpression =
@@ -1508,7 +1530,7 @@ let rec translate_expression (e : S.expression) (ctx : bs_ctx) : texpression =
   | Expansion (p, sv, exp) -> translate_expansion p sv exp ctx
   | IntroSymbolic (ectx, p, sv, v, e) ->
       translate_intro_symbolic ectx p sv v e ctx
-  | Meta (meta, e) -> translate_meta meta e ctx
+  | Meta (meta, e) -> translate_emeta meta e ctx
   | ForwardEnd (ectx, loop_input_values, e, back_e) ->
       translate_forward_end ectx loop_input_values e back_e ctx
   | Loop loop -> translate_loop loop ctx
@@ -1645,7 +1667,7 @@ and translate_function_call (call : S.call) (e : S.expression) (ctx : bs_ctx) :
   log#ldebug
     (lazy
       ("translate_function_call:\n"
-      ^ ctx_egeneric_args_to_string ctx call.generics));
+      ^ ctx_generic_args_to_string ctx call.generics));
   (* Translate the function call *)
   let generics = ctx_translate_fwd_generic_args ctx call.generics in
   let args =
@@ -1787,13 +1809,13 @@ and translate_end_abstraction_synth_input (ectx : C.eval_ctx) (abs : V.abs)
   log#ldebug
     (lazy
       ("translate_end_abstraction_synth_input:" ^ "\n- function: "
-      ^ Print.name_to_string ctx.fun_decl.name
+      ^ name_to_string ctx ctx.fun_decl.name
       ^ "\n- rg_id: "
       ^ T.RegionGroupId.to_string rg_id
       ^ "\n- loop_id: "
       ^ Print.option_to_string Pure.LoopId.to_string ctx.loop_id
-      ^ "\n- eval_ctx:\n" ^ IU.eval_ctx_to_string ectx ^ "\n- abs:\n"
-      ^ IU.abs_to_string ectx abs ^ "\n"));
+      ^ "\n- eval_ctx:\n" ^ eval_ctx_to_string ectx ^ "\n- abs:\n"
+      ^ abs_to_string ctx abs ^ "\n"));
 
   (* When we end an input abstraction, this input abstraction gets back
    * the borrows which it introduced in the context through the input
@@ -1845,11 +1867,12 @@ and translate_end_abstraction_synth_input (ectx : C.eval_ctx) (abs : V.abs)
       ("translate_end_abstraction_synth_input:"
      ^ "\n\n- given back variables types:\n"
       ^ Print.list_to_string
-          (fun (v : var) -> ty_to_string ctx v.ty)
+          (fun (v : var) -> pure_ty_to_string ctx v.ty)
           given_back_variables
       ^ "\n\n- consumed values:\n"
       ^ Print.list_to_string
-          (fun e -> texpression_to_string ctx e ^ " : " ^ ty_to_string ctx e.ty)
+          (fun e ->
+            texpression_to_string ctx e ^ " : " ^ pure_ty_to_string ctx e.ty)
           consumed_values
       ^ "\n"));
 
@@ -1948,7 +1971,8 @@ and translate_end_abstraction_fun_call (ectx : C.eval_ctx) (abs : V.abs)
              ^ "\n- inst_sg.inputs ("
              ^ string_of_int (List.length inst_sg.inputs)
              ^ "): "
-             ^ String.concat ", " (List.map (ty_to_string ctx) inst_sg.inputs)));
+             ^ String.concat ", "
+                 (List.map (pure_ty_to_string ctx) inst_sg.inputs)));
          List.iter
            (fun (x, ty) -> assert ((x : texpression).ty = ty))
            (List.combine inputs inst_sg.inputs);
@@ -2070,8 +2094,9 @@ and translate_end_abstraction_synth_ret (ectx : C.eval_ctx) (abs : V.abs)
       log#ldebug
         (lazy
           ("\n- given_back ty: "
-          ^ ty_to_string ctx given_back.ty
-          ^ "\n- sig input ty: " ^ ty_to_string ctx input.ty));
+          ^ pure_ty_to_string ctx given_back.ty
+          ^ "\n- sig input ty: "
+          ^ pure_ty_to_string ctx input.ty));
       assert (given_back.ty = input.ty))
     given_back_inputs;
   (* Translate the next expression *)
@@ -2098,7 +2123,7 @@ and translate_end_abstraction_loop (ectx : C.eval_ctx) (abs : V.abs)
       (* Actually the same case as [SynthInput] *)
       translate_end_abstraction_synth_input ectx abs e ctx rg_id
   | V.LoopCall ->
-      let fun_id = E.Regular ctx.fun_decl.A.def_id in
+      let fun_id = E.FRegular ctx.fun_decl.def_id in
       let effect_info =
         get_fun_effect_info ctx.fun_context.fun_infos (FunId fun_id)
           (Some vloop_id) (Some rg_id)
@@ -2202,7 +2227,7 @@ and translate_end_abstraction_loop (ectx : C.eval_ctx) (abs : V.abs)
                 var_values
             in
             let vars, values = List.split var_values in
-            mk_meta_symbolic_assignments vars values next_e
+            mk_emeta_symbolic_assignments vars values next_e
           else next_e
         in
 
@@ -2229,7 +2254,7 @@ and translate_assertion (ectx : C.eval_ctx) (v : V.typed_value)
   let func =
     { id = FunOrOp (Fun (Pure Assert)); generics = empty_generic_args }
   in
-  let func_ty = mk_arrow (Literal Bool) mk_unit_ty in
+  let func_ty = mk_arrow (TLiteral TBool) mk_unit_ty in
   let func = { e = Qualif func; ty = func_ty } in
   let assertion = mk_apps func args in
   mk_let monadic (mk_dummy_pattern mk_unit_ty) assertion next_e
@@ -2325,12 +2350,12 @@ and translate_expansion (p : S.mplace option) (sv : V.symbolic_value)
         (* We don't need to update the context: we don't introduce any
            * new values/variables *)
         let branch = translate_expression branch_e ctx in
-        let pat = mk_typed_pattern_from_literal (PV.Scalar v) in
+        let pat = mk_typed_pattern_from_literal (VScalar v) in
         { pat; branch }
       in
       let branches = List.map translate_branch branches in
       let otherwise = translate_expression otherwise ctx in
-      let pat_ty = Literal (Integer int_ty) in
+      let pat_ty = TLiteral (TInteger int_ty) in
       let otherwise_pat : typed_pattern = { value = PatDummy; ty = pat_ty } in
       let otherwise : match_branch =
         { pat = otherwise_pat; branch = otherwise }
@@ -2379,7 +2404,7 @@ and translate_ExpandAdt_one_branch (sv : V.symbolic_value)
   let ctx, vars = fresh_vars_for_symbolic_values svl ctx in
   let branch = translate_expression branch ctx in
   match type_id with
-  | T.AdtId adt_id ->
+  | TAdtId adt_id ->
       (* Detect if this is an enumeration or not *)
       let tdef = bs_ctx_lookup_llbc_type_decl adt_id ctx in
       let is_enum = TypesUtils.type_decl_is_enum tdef in
@@ -2426,14 +2451,14 @@ and translate_ExpandAdt_one_branch (sv : V.symbolic_value)
             let field_proj = gen_field_proj fid var in
             mk_let monadic (mk_typed_pattern_from_var var None) field_proj e)
           id_var_pairs branch
-  | T.Tuple ->
+  | TTuple ->
       let vars = List.map (fun x -> mk_typed_pattern_from_var x None) vars in
       let monadic = false in
       mk_let monadic
         (mk_simpl_tuple_pattern vars)
         (mk_opt_mplace_texpression scrutinee_mplace scrutinee)
         branch
-  | T.Assumed T.Box ->
+  | TAssumed TBox ->
       (* There should be exactly one variable *)
       let var =
         match vars with [ v ] -> v | _ -> raise (Failure "Unreachable")
@@ -2445,7 +2470,7 @@ and translate_ExpandAdt_one_branch (sv : V.symbolic_value)
         (mk_typed_pattern_from_var var None)
         (mk_opt_mplace_texpression scrutinee_mplace scrutinee)
         branch
-  | T.Assumed (T.Array | T.Slice | T.Str) ->
+  | TAssumed (TArray | TSlice | TStr) ->
       (* We can't expand those values: we can access the fields only
        * through the functions provided by the API (note that we don't
        * know how to expand values like vectors or arrays, because they have a variable number
@@ -2469,19 +2494,19 @@ and translate_intro_symbolic (ectx : C.eval_ctx) (p : S.mplace option)
   *)
   let v =
     match v with
-    | SingleValue v -> typed_value_to_texpression ctx ectx v
-    | Array values ->
+    | VaSingleValue v -> typed_value_to_texpression ctx ectx v
+    | VaArray values ->
         (* We use a struct update to encode the array aggregate, in order
            to preserve the structure and allow generating code of the shape
            `[x0, ...., xn]` *)
         let values = List.map (typed_value_to_texpression ctx ectx) values in
         let values = FieldId.mapi (fun fid v -> (fid, v)) values in
         let su : struct_update =
-          { struct_id = Assumed Array; init = None; updates = values }
+          { struct_id = TAssumed TArray; init = None; updates = values }
         in
         { e = StructUpdate su; ty = var.ty }
-    | ConstGenericValue cg_id -> { e = CVar cg_id; ty = var.ty }
-    | TraitConstValue (trait_ref, generics, const_name) ->
+    | VaCgValue cg_id -> { e = CVar cg_id; ty = var.ty }
+    | VaTraitConstValue (trait_ref, generics, const_name) ->
         let type_infos = ctx.type_context.type_infos in
         let trait_ref = translate_fwd_trait_ref type_infos trait_ref in
         let generics = translate_fwd_generic_args type_infos generics in
@@ -2558,7 +2583,7 @@ and translate_forward_end (ectx : C.eval_ctx)
       let org_args = args in
 
       (* Lookup the effect info for the loop function *)
-      let fid = E.Regular ctx.fun_decl.A.def_id in
+      let fid = E.FRegular ctx.fun_decl.def_id in
       let effect_info =
         get_fun_effect_info ctx.fun_context.fun_infos (FunId fid) None ctx.bid
       in
@@ -2633,7 +2658,7 @@ and translate_forward_end (ectx : C.eval_ctx)
          We then remove all the meta information from the body *before* calling
          {!PureMicroPasses.decompose_loops}.
       *)
-      mk_meta_symbolic_assignments loop_info.input_vars org_args e
+      mk_emeta_symbolic_assignments loop_info.input_vars org_args e
 
 and translate_loop (loop : S.loop) (ctx : bs_ctx) : texpression =
   let loop_id = V.LoopId.Map.find loop.loop_id ctx.loop_ids_map in
@@ -2661,7 +2686,7 @@ and translate_loop (loop : S.loop) (ctx : bs_ctx) : texpression =
         ^ T.RegionGroupId.Map.show
             (fun (rids, tys) ->
               "(" ^ T.RegionId.Set.show rids ^ ", "
-              ^ Print.list_to_string (rty_to_string ctx) tys
+              ^ Print.list_to_string (ty_to_string ctx) tys
               ^ ")")
             loop.rg_to_given_back_tys
         ^ "\n"));
@@ -2728,12 +2753,10 @@ and translate_loop (loop : S.loop) (ctx : bs_ctx) : texpression =
        call to the loop forward function) *)
     let generics =
       let { types; const_generics; trait_clauses } = ctx.sg.generics in
-      let types =
-        List.map (fun (ty : T.type_var) -> TypeVar ty.T.index) types
-      in
+      let types = List.map (fun (ty : T.type_var) -> TVar ty.T.index) types in
       let const_generics =
         List.map
-          (fun (cg : T.const_generic_var) -> T.ConstGenericVar cg.T.index)
+          (fun (cg : T.const_generic_var) -> T.CgVar cg.T.index)
           const_generics
       in
       let trait_refs =
@@ -2793,6 +2816,7 @@ and translate_loop (loop : S.loop) (ctx : bs_ctx) : texpression =
       {
         fun_end;
         loop_id;
+        meta = loop.meta;
         fuel0 = ctx.fuel0;
         fuel = ctx.fuel;
         input_state;
@@ -2808,7 +2832,7 @@ and translate_loop (loop : S.loop) (ctx : bs_ctx) : texpression =
   let ty = fun_end.ty in
   { e = loop; ty }
 
-and translate_meta (meta : S.meta) (e : S.expression) (ctx : bs_ctx) :
+and translate_emeta (meta : S.emeta) (e : S.expression) (ctx : bs_ctx) :
     texpression =
   let next_e = translate_expression e ctx in
   let meta =
@@ -2909,24 +2933,28 @@ let translate_fun_decl (ctx : bs_ctx) (body : S.expression option) : fun_decl =
   log#ldebug
     (lazy
       ("SymbolicToPure.translate_fun_decl: "
-      ^ Print.fun_name_to_string def.A.name
+      ^ name_to_string ctx def.name
       ^ " ("
       ^ Print.option_to_string T.RegionGroupId.to_string bid
       ^ ")\n"));
 
   (* Translate the declaration *)
-  let def_id = def.A.def_id in
-  let basename = def.name in
+  let def_id = def.def_id in
+  let llbc_name = def.name in
+  let name = name_to_string ctx llbc_name in
   (* Retrieve the signature *)
   let signature = ctx.sg in
+  let regions_hierarchy =
+    FunIdMap.find (FRegular def_id) ctx.fun_context.regions_hierarchies
+  in
   (* Translate the body, if there is *)
   let body =
     match body with
     | None -> None
     | Some body ->
         let effect_info =
-          get_fun_effect_info ctx.fun_context.fun_infos (FunId (Regular def_id))
-            None bid
+          get_fun_effect_info ctx.fun_context.fun_infos
+            (FunId (FRegular def_id)) None bid
         in
         let body = translate_expression body ctx in
         (* Add a match over the fuel, if necessary *)
@@ -2960,7 +2988,7 @@ let translate_fun_decl (ctx : bs_ctx) (body : S.expression option) : fun_decl =
           | None -> []
           | Some back_id ->
               let parents_ids =
-                list_ordered_ancestor_region_groups def.signature back_id
+                list_ordered_ancestor_region_groups regions_hierarchy back_id
               in
               let backward_ids = List.append parents_ids [ back_id ] in
               List.concat
@@ -2987,7 +3015,7 @@ let translate_fun_decl (ctx : bs_ctx) (body : S.expression option) : fun_decl =
         log#ldebug
           (lazy
             ("SymbolicToPure.translate_fun_decl: "
-            ^ Print.fun_name_to_string def.A.name
+            ^ name_to_string ctx def.name
             ^ " ("
             ^ Print.option_to_string T.RegionGroupId.to_string bid
             ^ ")" ^ "\n- forward_inputs: "
@@ -2999,8 +3027,8 @@ let translate_fun_decl (ctx : bs_ctx) (body : S.expression option) : fun_decl =
             ^ "\n- back_state: "
             ^ String.concat ", " (List.map show_var back_state)
             ^ "\n- signature.inputs: "
-            ^ String.concat ", " (List.map (ty_to_string ctx) signature.inputs)
-            ));
+            ^ String.concat ", "
+                (List.map (pure_ty_to_string ctx) signature.inputs)));
         (* TODO: we need to normalize the types *)
         if !Config.type_check_pure_code then
           assert (
@@ -3018,14 +3046,17 @@ let translate_fun_decl (ctx : bs_ctx) (body : S.expression option) : fun_decl =
   let loop_id = None in
 
   (* Assemble the declaration *)
-  let def =
+  let def : fun_decl =
     {
       def_id;
+      is_local = def.is_local;
+      meta = def.meta;
       kind = def.kind;
       num_loops;
       loop_id;
       back_id = bid;
-      basename;
+      llbc_name;
+      name;
       signature;
       is_global_decl_body = def.is_global_decl_body;
       body;
@@ -3039,8 +3070,9 @@ let translate_fun_decl (ctx : bs_ctx) (body : S.expression option) : fun_decl =
   (* return *)
   def
 
-let translate_type_decls (type_decls : T.type_decl list) : type_decl list =
-  List.map translate_type_decl type_decls
+let translate_type_decls (ctx : Contexts.decls_ctx) : type_decl list =
+  List.map (translate_type_decl ctx)
+    (TypeDeclId.Map.values ctx.type_ctx.type_decls)
 
 (** Translates function signatures.
 
@@ -3064,19 +3096,23 @@ let translate_fun_signatures (decls_ctx : C.decls_ctx)
   let translate_one (fun_id : A.fun_id) (input_names : string option list)
       (sg : A.fun_sig) : (regular_fun_id_not_loop * fun_sig_named_outputs) list
       =
+    (* Retrieve the regions hierarchy *)
+    let regions_hierarchy =
+      FunIdMap.find fun_id decls_ctx.fun_ctx.regions_hierarchies
+    in
     (* The forward function *)
     let fwd_sg = translate_fun_sig decls_ctx fun_id sg input_names None in
     let fwd_id = (fun_id, None) in
     (* The backward functions *)
     let back_sgs =
       List.map
-        (fun (rg : T.region_var_group) ->
+        (fun (rg : T.region_group) ->
           let tsg =
             translate_fun_sig decls_ctx fun_id sg input_names (Some rg.id)
           in
           let id = (fun_id, Some rg.id) in
           (id, tsg))
-        sg.regions_hierarchy
+        regions_hierarchy
     in
     (* Return *)
     (fwd_id, fwd_sg) :: back_sgs
@@ -3089,14 +3125,16 @@ let translate_fun_signatures (decls_ctx : C.decls_ctx)
     (fun m (id, sg) -> RegularFunIdNotLoopMap.add id sg m)
     RegularFunIdNotLoopMap.empty translated
 
-let translate_trait_decl (type_infos : TA.type_infos)
-    (trait_decl : A.trait_decl) : trait_decl =
+let translate_trait_decl (ctx : Contexts.decls_ctx) (trait_decl : A.trait_decl)
+    : trait_decl =
   let {
     def_id;
-    name;
-    generics;
+    is_local;
+    name = llbc_name;
+    meta;
+    generics = llbc_generics;
     preds;
-    parent_clauses;
+    parent_clauses = llbc_parent_clauses;
     consts;
     types;
     required_methods;
@@ -3104,9 +3142,15 @@ let translate_trait_decl (type_infos : TA.type_infos)
   } : A.trait_decl =
     trait_decl
   in
-  let generics = translate_generic_params generics in
+  let type_infos = ctx.type_ctx.type_infos in
+  let name =
+    Print.Types.name_to_string
+      (Print.Contexts.decls_ctx_to_fmt_env ctx)
+      llbc_name
+  in
+  let generics = translate_generic_params llbc_generics in
   let preds = translate_predicates preds in
-  let parent_clauses = List.map translate_trait_clause parent_clauses in
+  let parent_clauses = List.map translate_trait_clause llbc_parent_clauses in
   let consts =
     List.map
       (fun (name, (ty, id)) -> (name, (translate_fwd_ty type_infos ty, id)))
@@ -3122,23 +3166,30 @@ let translate_trait_decl (type_infos : TA.type_infos)
   in
   {
     def_id;
+    is_local;
+    llbc_name;
     name;
+    meta;
     generics;
+    llbc_generics;
     preds;
     parent_clauses;
+    llbc_parent_clauses;
     consts;
     types;
     required_methods;
     provided_methods;
   }
 
-let translate_trait_impl (type_infos : TA.type_infos)
-    (trait_impl : A.trait_impl) : trait_impl =
+let translate_trait_impl (ctx : Contexts.decls_ctx) (trait_impl : A.trait_impl)
+    : trait_impl =
   let {
     A.def_id;
-    name;
-    impl_trait;
-    generics;
+    is_local;
+    name = llbc_name;
+    meta;
+    impl_trait = llbc_impl_trait;
+    generics = llbc_generics;
     preds;
     parent_trait_refs;
     consts;
@@ -3148,10 +3199,16 @@ let translate_trait_impl (type_infos : TA.type_infos)
   } =
     trait_impl
   in
+  let type_infos = ctx.type_ctx.type_infos in
   let impl_trait =
-    translate_trait_decl_ref (translate_fwd_ty type_infos) impl_trait
+    translate_trait_decl_ref (translate_fwd_ty type_infos) llbc_impl_trait
+  in
+  let name =
+    Print.Types.name_to_string
+      (Print.Contexts.decls_ctx_to_fmt_env ctx)
+      llbc_name
   in
-  let generics = translate_generic_params generics in
+  let generics = translate_generic_params llbc_generics in
   let preds = translate_predicates preds in
   let parent_trait_refs = List.map translate_strait_ref parent_trait_refs in
   let consts =
@@ -3169,9 +3226,14 @@ let translate_trait_impl (type_infos : TA.type_infos)
   in
   {
     def_id;
+    is_local;
+    llbc_name;
     name;
+    meta;
     impl_trait;
+    llbc_impl_trait;
     generics;
+    llbc_generics;
     preds;
     parent_trait_refs;
     consts;
diff --git a/compiler/SynthesizeSymbolic.ml b/compiler/SynthesizeSymbolic.ml
index 9dd65c84..efcf001a 100644
--- a/compiler/SynthesizeSymbolic.ml
+++ b/compiler/SynthesizeSymbolic.ml
@@ -1,57 +1,51 @@
-module C = Collections
-module T = Types
-module PV = PrimitiveValues
-module V = Values
-module E = Expressions
-module A = LlbcAst
+open Types
+open TypesUtils
+open Expressions
+open Values
 open SymbolicAst
 
-let mk_mplace (p : E.place) (ctx : Contexts.eval_ctx) : mplace =
+let mk_mplace (p : place) (ctx : Contexts.eval_ctx) : mplace =
   let bv = Contexts.ctx_lookup_var_binder ctx p.var_id in
   { bv; projection = p.projection }
 
-let mk_opt_mplace (p : E.place option) (ctx : Contexts.eval_ctx) : mplace option
-    =
+let mk_opt_mplace (p : place option) (ctx : Contexts.eval_ctx) : mplace option =
   Option.map (fun p -> mk_mplace p ctx) p
 
-let mk_opt_place_from_op (op : E.operand) (ctx : Contexts.eval_ctx) :
+let mk_opt_place_from_op (op : operand) (ctx : Contexts.eval_ctx) :
     mplace option =
-  match op with
-  | E.Copy p | E.Move p -> Some (mk_mplace p ctx)
-  | E.Constant _ -> None
+  match op with Copy p | Move p -> Some (mk_mplace p ctx) | Constant _ -> None
 
-let mk_meta (m : meta) (e : expression) : expression = Meta (m, e)
+let mk_emeta (m : emeta) (e : expression) : expression = Meta (m, e)
 
-let synthesize_symbolic_expansion (sv : V.symbolic_value)
-    (place : mplace option) (seel : V.symbolic_expansion option list)
-    (el : expression list option) : expression option =
+let synthesize_symbolic_expansion (sv : symbolic_value) (place : mplace option)
+    (seel : symbolic_expansion option list) (el : expression list option) :
+    expression option =
   match el with
   | None -> None
   | Some el ->
       let ls = List.combine seel el in
       (* Match on the symbolic value type to know which can of expansion happened *)
       let expansion =
-        match sv.V.sv_ty with
-        | T.Literal PV.Bool -> (
+        match sv.sv_ty with
+        | TLiteral TBool -> (
             (* Boolean expansion: there should be two branches *)
             match ls with
             | [
-             (Some (V.SeLiteral (PV.Bool true)), true_exp);
-             (Some (V.SeLiteral (PV.Bool false)), false_exp);
+             (Some (SeLiteral (VBool true)), true_exp);
+             (Some (SeLiteral (VBool false)), false_exp);
             ] ->
                 ExpandBool (true_exp, false_exp)
             | _ -> raise (Failure "Ill-formed boolean expansion"))
-        | T.Literal (PV.Integer int_ty) ->
+        | TLiteral (TInteger int_ty) ->
             (* Switch over an integer: split between the "regular" branches
                and the "otherwise" branch (which should be the last branch) *)
-            let branches, otherwise = C.List.pop_last ls in
+            let branches, otherwise = Collections.List.pop_last ls in
             (* For all the regular branches, the symbolic value should have
              * been expanded to a constant *)
-            let get_scalar (see : V.symbolic_expansion option) : V.scalar_value
-                =
+            let get_scalar (see : symbolic_expansion option) : scalar_value =
               match see with
-              | Some (V.SeLiteral (PV.Scalar cv)) ->
-                  assert (cv.PV.int_ty = int_ty);
+              | Some (SeLiteral (VScalar cv)) ->
+                  assert (cv.int_ty = int_ty);
                   cv
               | _ -> raise (Failure "Unreachable")
             in
@@ -64,12 +58,12 @@ let synthesize_symbolic_expansion (sv : V.symbolic_value)
             assert (otherwise_see = None);
             (* Return *)
             ExpandInt (int_ty, branches, otherwise)
-        | T.Adt (_, _) ->
+        | TAdt (_, _) ->
             (* Branching: it is necessarily an enumeration expansion *)
-            let get_variant (see : V.symbolic_expansion option) :
-                T.VariantId.id option * V.symbolic_value list =
+            let get_variant (see : symbolic_expansion option) :
+                VariantId.id option * symbolic_value list =
               match see with
-              | Some (V.SeAdt (vid, fields)) -> (vid, fields)
+              | Some (SeAdt (vid, fields)) -> (vid, fields)
               | _ -> raise (Failure "Ill-formed branching ADT expansion")
             in
             let exp =
@@ -80,29 +74,28 @@ let synthesize_symbolic_expansion (sv : V.symbolic_value)
                 ls
             in
             ExpandAdt exp
-        | T.Ref (_, _, _) -> (
+        | TRef (_, _, _) -> (
             (* Reference expansion: there should be one branch *)
             match ls with
             | [ (Some see, exp) ] -> ExpandNoBranch (see, exp)
             | _ -> raise (Failure "Ill-formed borrow expansion"))
-        | T.TypeVar _
-        | T.Literal Char
-        | Never | T.TraitType _ | T.Arrow _ | T.RawPtr _ ->
+        | TVar _ | TLiteral TChar | TNever | TTraitType _ | TArrow _ | TRawPtr _
+          ->
             raise (Failure "Ill-formed symbolic expansion")
       in
       Some (Expansion (place, sv, expansion))
 
-let synthesize_symbolic_expansion_no_branching (sv : V.symbolic_value)
-    (place : mplace option) (see : V.symbolic_expansion) (e : expression option)
-    : expression option =
+let synthesize_symbolic_expansion_no_branching (sv : symbolic_value)
+    (place : mplace option) (see : symbolic_expansion) (e : expression option) :
+    expression option =
   let el = Option.map (fun e -> [ e ]) e in
   synthesize_symbolic_expansion sv place [ Some see ] el
 
 let synthesize_function_call (call_id : call_id) (ctx : Contexts.eval_ctx)
-    (abstractions : V.AbstractionId.id list) (generics : T.egeneric_args)
-    (args : V.typed_value list) (args_places : mplace option list)
-    (dest : V.symbolic_value) (dest_place : mplace option)
-    (e : expression option) : expression option =
+    (abstractions : AbstractionId.id list) (generics : generic_args)
+    (args : typed_value list) (args_places : mplace option list)
+    (dest : symbolic_value) (dest_place : mplace option) (e : expression option)
+    : expression option =
   Option.map
     (fun e ->
       let call =
@@ -120,60 +113,58 @@ let synthesize_function_call (call_id : call_id) (ctx : Contexts.eval_ctx)
       FunCall (call, e))
     e
 
-let synthesize_global_eval (gid : A.GlobalDeclId.id) (dest : V.symbolic_value)
+let synthesize_global_eval (gid : GlobalDeclId.id) (dest : symbolic_value)
     (e : expression option) : expression option =
   Option.map (fun e -> EvalGlobal (gid, dest, e)) e
 
-let synthesize_regular_function_call (fun_id : A.fun_id_or_trait_method_ref)
-    (call_id : V.FunCallId.id) (ctx : Contexts.eval_ctx)
-    (abstractions : V.AbstractionId.id list) (generics : T.egeneric_args)
-    (args : V.typed_value list) (args_places : mplace option list)
-    (dest : V.symbolic_value) (dest_place : mplace option)
-    (e : expression option) : expression option =
+let synthesize_regular_function_call (fun_id : fun_id_or_trait_method_ref)
+    (call_id : FunCallId.id) (ctx : Contexts.eval_ctx)
+    (abstractions : AbstractionId.id list) (generics : generic_args)
+    (args : typed_value list) (args_places : mplace option list)
+    (dest : symbolic_value) (dest_place : mplace option) (e : expression option)
+    : expression option =
   synthesize_function_call
     (Fun (fun_id, call_id))
     ctx abstractions generics args args_places dest dest_place e
 
-let synthesize_unary_op (ctx : Contexts.eval_ctx) (unop : E.unop)
-    (arg : V.typed_value) (arg_place : mplace option) (dest : V.symbolic_value)
+let synthesize_unary_op (ctx : Contexts.eval_ctx) (unop : unop)
+    (arg : typed_value) (arg_place : mplace option) (dest : symbolic_value)
     (dest_place : mplace option) (e : expression option) : expression option =
-  let generics = TypesUtils.mk_empty_generic_args in
+  let generics = empty_generic_args in
   synthesize_function_call (Unop unop) ctx [] generics [ arg ] [ arg_place ]
     dest dest_place e
 
-let synthesize_binary_op (ctx : Contexts.eval_ctx) (binop : E.binop)
-    (arg0 : V.typed_value) (arg0_place : mplace option) (arg1 : V.typed_value)
-    (arg1_place : mplace option) (dest : V.symbolic_value)
+let synthesize_binary_op (ctx : Contexts.eval_ctx) (binop : binop)
+    (arg0 : typed_value) (arg0_place : mplace option) (arg1 : typed_value)
+    (arg1_place : mplace option) (dest : symbolic_value)
     (dest_place : mplace option) (e : expression option) : expression option =
-  let generics = TypesUtils.mk_empty_generic_args in
+  let generics = empty_generic_args in
   synthesize_function_call (Binop binop) ctx [] generics [ arg0; arg1 ]
     [ arg0_place; arg1_place ] dest dest_place e
 
-let synthesize_end_abstraction (ctx : Contexts.eval_ctx) (abs : V.abs)
+let synthesize_end_abstraction (ctx : Contexts.eval_ctx) (abs : abs)
     (e : expression option) : expression option =
   Option.map (fun e -> EndAbstraction (ctx, abs, e)) e
 
 let synthesize_assignment (ctx : Contexts.eval_ctx) (lplace : mplace)
-    (rvalue : V.typed_value) (rplace : mplace option) (e : expression option) :
+    (rvalue : typed_value) (rplace : mplace option) (e : expression option) :
     expression option =
   Option.map (fun e -> Meta (Assignment (ctx, lplace, rvalue, rplace), e)) e
 
-let synthesize_assertion (ctx : Contexts.eval_ctx) (v : V.typed_value)
+let synthesize_assertion (ctx : Contexts.eval_ctx) (v : typed_value)
     (e : expression option) =
   Option.map (fun e -> Assertion (ctx, v, e)) e
 
 let synthesize_forward_end (ctx : Contexts.eval_ctx)
-    (loop_input_values : V.typed_value V.SymbolicValueId.Map.t option)
-    (e : expression) (el : expression T.RegionGroupId.Map.t) =
+    (loop_input_values : typed_value SymbolicValueId.Map.t option)
+    (e : expression) (el : expression RegionGroupId.Map.t) =
   Some (ForwardEnd (ctx, loop_input_values, e, el))
 
-let synthesize_loop (loop_id : V.LoopId.id)
-    (input_svalues : V.symbolic_value list)
-    (fresh_svalues : V.SymbolicValueId.Set.t)
-    (rg_to_given_back_tys :
-      (T.RegionId.Set.t * T.rty list) T.RegionGroupId.Map.t)
-    (end_expr : expression option) (loop_expr : expression option) :
-    expression option =
+let synthesize_loop (loop_id : LoopId.id) (input_svalues : symbolic_value list)
+    (fresh_svalues : SymbolicValueId.Set.t)
+    (rg_to_given_back_tys : (RegionId.Set.t * ty list) RegionGroupId.Map.t)
+    (end_expr : expression option) (loop_expr : expression option)
+    (meta : Meta.meta) : expression option =
   match (end_expr, loop_expr) with
   | None, None -> None
   | Some end_expr, Some loop_expr ->
@@ -186,5 +177,6 @@ let synthesize_loop (loop_id : V.LoopId.id)
              rg_to_given_back_tys;
              end_expr;
              loop_expr;
+             meta;
            })
   | _ -> raise (Failure "Unreachable")
diff --git a/compiler/Translate.ml b/compiler/Translate.ml
index a3d96023..05e48af5 100644
--- a/compiler/Translate.ml
+++ b/compiler/Translate.ml
@@ -1,11 +1,11 @@
-open InterpreterStatements
 open Interpreter
-module L = Logging
-module T = Types
-module A = LlbcAst
+open Expressions
+open Types
+open Values
+open LlbcAst
+open Contexts
 module SA = SymbolicAst
 module Micro = PureMicroPasses
-module C = Contexts
 open PureUtils
 open TranslateCore
 
@@ -16,18 +16,17 @@ let log = TranslateCore.log
     - the list of symbolic values used for the input values
     - the generated symbolic AST
 *)
-type symbolic_fun_translation = V.symbolic_value list * SA.expression
+type symbolic_fun_translation = symbolic_value list * SA.expression
 
 (** Execute the symbolic interpreter on a function to generate a list of symbolic ASTs,
     for the forward function and the backward functions.
 *)
-let translate_function_to_symbolics (trans_ctx : trans_ctx) (fdef : A.fun_decl)
-    : symbolic_fun_translation option =
+let translate_function_to_symbolics (trans_ctx : trans_ctx) (fdef : fun_decl) :
+    symbolic_fun_translation option =
   (* Debug *)
   log#ldebug
     (lazy
-      ("translate_function_to_symbolics: "
-      ^ Print.fun_name_to_string fdef.A.name));
+      ("translate_function_to_symbolics: " ^ name_to_string trans_ctx fdef.name));
 
   match fdef.body with
   | None -> None
@@ -45,12 +44,11 @@ let translate_function_to_symbolics (trans_ctx : trans_ctx) (fdef : A.fun_decl)
 *)
 let translate_function_to_pure (trans_ctx : trans_ctx)
     (fun_sigs : SymbolicToPure.fun_sig_named_outputs RegularFunIdNotLoopMap.t)
-    (pure_type_decls : Pure.type_decl Pure.TypeDeclId.Map.t) (fdef : A.fun_decl)
-    : pure_fun_translation_no_loops =
+    (pure_type_decls : Pure.type_decl Pure.TypeDeclId.Map.t) (fdef : fun_decl) :
+    pure_fun_translation_no_loops =
   (* Debug *)
   log#ldebug
-    (lazy
-      ("translate_function_to_pure: " ^ Print.fun_name_to_string fdef.A.name));
+    (lazy ("translate_function_to_pure: " ^ name_to_string trans_ctx fdef.name));
 
   let def_id = fdef.def_id in
 
@@ -61,22 +59,24 @@ let translate_function_to_pure (trans_ctx : trans_ctx)
 
   (* Initialize the context *)
   let forward_sig =
-    RegularFunIdNotLoopMap.find (E.Regular def_id, None) fun_sigs
+    RegularFunIdNotLoopMap.find (FRegular def_id, None) fun_sigs
   in
-  let sv_to_var = V.SymbolicValueId.Map.empty in
+  let sv_to_var = SymbolicValueId.Map.empty in
   let var_counter = Pure.VarId.generator_zero in
   let state_var, var_counter = Pure.VarId.fresh var_counter in
   let back_state_var, var_counter = Pure.VarId.fresh var_counter in
   let fuel0, var_counter = Pure.VarId.fresh var_counter in
   let fuel, var_counter = Pure.VarId.fresh var_counter in
-  let calls = V.FunCallId.Map.empty in
-  let abstractions = V.AbstractionId.Map.empty in
+  let calls = FunCallId.Map.empty in
+  let abstractions = AbstractionId.Map.empty in
   let recursive_type_decls =
-    T.TypeDeclId.Set.of_list
+    TypeDeclId.Set.of_list
       (List.filter_map
          (fun (tid, g) ->
-           match g with Charon.GAst.NonRec _ -> None | Rec _ -> Some tid)
-         (T.TypeDeclId.Map.bindings trans_ctx.type_ctx.type_decls_groups))
+           match g with
+           | Charon.GAst.NonRecGroup _ -> None
+           | RecGroup _ -> Some tid)
+         (TypeDeclId.Map.bindings trans_ctx.type_ctx.type_decls_groups))
   in
   let type_context =
     {
@@ -91,6 +91,7 @@ let translate_function_to_pure (trans_ctx : trans_ctx)
       SymbolicToPure.llbc_fun_decls = trans_ctx.fun_ctx.fun_decls;
       fun_sigs;
       fun_infos = trans_ctx.fun_ctx.fun_infos;
+      regions_hierarchies = trans_ctx.fun_ctx.regions_hierarchies;
     }
   in
   let global_context =
@@ -103,9 +104,9 @@ let translate_function_to_pure (trans_ctx : trans_ctx)
   *)
   let loop_ids_map =
     match symbolic_trans with
-    | None -> V.LoopId.Map.empty
+    | None -> LoopId.Map.empty
     | Some (_, ast) ->
-        let m = ref V.LoopId.Map.empty in
+        let m = ref LoopId.Map.empty in
         let _, fresh_loop_id = Pure.LoopId.fresh_stateful_generator () in
 
         let visitor =
@@ -114,10 +115,9 @@ let translate_function_to_pure (trans_ctx : trans_ctx)
 
             method! visit_loop env loop =
               let _ =
-                match V.LoopId.Map.find_opt loop.loop_id !m with
+                match LoopId.Map.find_opt loop.loop_id !m with
                 | Some _ -> ()
-                | None ->
-                    m := V.LoopId.Map.add loop.loop_id (fresh_loop_id ()) !m
+                | None -> m := LoopId.Map.add loop.loop_id (fresh_loop_id ()) !m
               in
               super#visit_loop env loop
           end
@@ -147,9 +147,9 @@ let translate_function_to_pure (trans_ctx : trans_ctx)
       fun_decl = fdef;
       forward_inputs = [];
       (* Empty for now *)
-      backward_inputs = T.RegionGroupId.Map.empty;
+      backward_inputs = RegionGroupId.Map.empty;
       (* Empty for now *)
-      backward_outputs = T.RegionGroupId.Map.empty;
+      backward_outputs = RegionGroupId.Map.empty;
       loop_backward_outputs = None;
       (* Empty for now *)
       calls;
@@ -170,7 +170,7 @@ let translate_function_to_pure (trans_ctx : trans_ctx)
     | Some body, Some (input_svs, _) ->
         let forward_input_vars = LlbcAstUtils.fun_body_get_input_vars body in
         let forward_input_varnames =
-          List.map (fun (v : A.var) -> v.name) forward_input_vars
+          List.map (fun (v : var) -> v.name) forward_input_vars
         in
         let input_svs = List.combine forward_input_varnames input_svs in
         let ctx, forward_inputs =
@@ -188,7 +188,7 @@ let translate_function_to_pure (trans_ctx : trans_ctx)
   in
 
   (* Translate the backward functions *)
-  let translate_backward (rg : T.region_var_group) : Pure.fun_decl =
+  let translate_backward (rg : region_group) : Pure.fun_decl =
     (* For the backward inputs/outputs initialization: we use the fact that
      * there are no nested borrows for now, and so that the region groups
      * can't have parents *)
@@ -200,7 +200,7 @@ let translate_function_to_pure (trans_ctx : trans_ctx)
         (* Initialize the context - note that the ret_ty is not really
          * useful as we don't translate a body *)
         let backward_sg =
-          RegularFunIdNotLoopMap.find (Regular def_id, Some back_id) fun_sigs
+          RegularFunIdNotLoopMap.find (FRegular def_id, Some back_id) fun_sigs
         in
         let ctx = { ctx with bid = Some back_id; sg = backward_sg.sg } in
 
@@ -211,7 +211,7 @@ let translate_function_to_pure (trans_ctx : trans_ctx)
            variables required by the backward function.
         *)
         let backward_sg =
-          RegularFunIdNotLoopMap.find (Regular def_id, Some back_id) fun_sigs
+          RegularFunIdNotLoopMap.find (FRegular def_id, Some back_id) fun_sigs
         in
         (* We need to ignore the forward inputs, and the state input (if there is) *)
         let backward_inputs =
@@ -243,10 +243,10 @@ let translate_function_to_pure (trans_ctx : trans_ctx)
           SymbolicToPure.fresh_vars backward_outputs ctx
         in
         let backward_inputs =
-          T.RegionGroupId.Map.singleton back_id backward_inputs
+          RegionGroupId.Map.singleton back_id backward_inputs
         in
         let backward_outputs =
-          T.RegionGroupId.Map.singleton back_id backward_outputs
+          RegionGroupId.Map.singleton back_id backward_outputs
         in
 
         (* Put everything in the context *)
@@ -263,15 +263,17 @@ let translate_function_to_pure (trans_ctx : trans_ctx)
         (* Translate *)
         SymbolicToPure.translate_fun_decl ctx (Some symbolic)
   in
-  let pure_backwards =
-    List.map translate_backward fdef.signature.regions_hierarchy
+  let regions_hierarchy =
+    LlbcAstUtils.FunIdMap.find (FRegular fdef.def_id)
+      fun_context.regions_hierarchies
   in
+  let pure_backwards = List.map translate_backward regions_hierarchy in
 
   (* Return *)
   (pure_forward, pure_backwards)
 
 (* TODO: factor out the return type *)
-let translate_crate_to_pure (crate : A.crate) :
+let translate_crate_to_pure (crate : crate) :
     trans_ctx
     * Pure.type_decl list
     * pure_fun_translation list
@@ -284,9 +286,7 @@ let translate_crate_to_pure (crate : A.crate) :
   let trans_ctx = compute_contexts crate in
 
   (* Translate all the type definitions *)
-  let type_decls =
-    SymbolicToPure.translate_type_decls (T.TypeDeclId.Map.values crate.types)
-  in
+  let type_decls = SymbolicToPure.translate_type_decls trans_ctx in
 
   (* Compute the type definition map *)
   let type_decls_map =
@@ -298,24 +298,24 @@ let translate_crate_to_pure (crate : A.crate) :
   let assumed_sigs =
     List.map
       (fun (info : Assumed.assumed_fun_info) ->
-        ( E.Assumed info.fun_id,
+        ( FAssumed info.fun_id,
           List.map (fun _ -> None) info.fun_sig.inputs,
           info.fun_sig ))
       Assumed.assumed_fun_infos
   in
   let local_sigs =
     List.map
-      (fun (fdef : A.fun_decl) ->
+      (fun (fdef : fun_decl) ->
         let input_names =
           match fdef.body with
           | None -> List.map (fun _ -> None) fdef.signature.inputs
           | Some body ->
               List.map
-                (fun (v : A.var) -> v.name)
+                (fun (v : var) -> v.name)
                 (LlbcAstUtils.fun_body_get_input_vars body)
         in
-        (E.Regular fdef.def_id, input_names, fdef.signature))
-      (A.FunDeclId.Map.values crate.functions)
+        (FRegular fdef.def_id, input_names, fdef.signature))
+      (FunDeclId.Map.values crate.fun_decls)
   in
   let sigs = List.append assumed_sigs local_sigs in
   let fun_sigs = SymbolicToPure.translate_fun_signatures trans_ctx sigs in
@@ -324,22 +324,21 @@ let translate_crate_to_pure (crate : A.crate) :
   let pure_translations =
     List.map
       (translate_function_to_pure trans_ctx fun_sigs type_decls_map)
-      (A.FunDeclId.Map.values crate.functions)
+      (FunDeclId.Map.values crate.fun_decls)
   in
 
   (* Translate the trait declarations *)
-  let type_infos = trans_ctx.type_ctx.type_infos in
   let trait_decls =
     List.map
-      (SymbolicToPure.translate_trait_decl type_infos)
-      (T.TraitDeclId.Map.values trans_ctx.trait_decls_ctx.trait_decls)
+      (SymbolicToPure.translate_trait_decl trans_ctx)
+      (TraitDeclId.Map.values trans_ctx.trait_decls_ctx.trait_decls)
   in
 
   (* Translate the trait implementations *)
   let trait_impls =
     List.map
-      (SymbolicToPure.translate_trait_impl type_infos)
-      (T.TraitImplId.Map.values trans_ctx.trait_impls_ctx.trait_impls)
+      (SymbolicToPure.translate_trait_impl trans_ctx)
+      (TraitImplId.Map.values trans_ctx.trait_impls_ctx.trait_impls)
   in
 
   (* Apply the micro-passes *)
@@ -398,9 +397,9 @@ let crate_has_opaque_non_builtin_decls (ctx : gen_ctx) (filter_assumed : bool) :
   log#ldebug
     (lazy
       ("Opaque decls:" ^ "\n- types:\n"
-      ^ String.concat ",\n" (List.map T.show_type_decl types)
+      ^ String.concat ",\n" (List.map show_type_decl types)
       ^ "\n- functions:\n"
-      ^ String.concat ",\n" (List.map A.show_fun_decl funs)));
+      ^ String.concat ",\n" (List.map show_fun_decl funs)));
   (types <> [], funs <> [])
 
 (** Export a type declaration.
@@ -478,8 +477,7 @@ let export_types_group (fmt : Format.formatter) (config : gen_config)
     let types_map = builtin_types_map () in
     List.map
       (fun (def : Pure.type_decl) ->
-        let sname = name_to_simple_name def.name in
-        SimpleNameMap.find_opt sname types_map <> None)
+        match_name_find_opt ctx.trans_ctx def.llbc_name types_map <> None)
       defs
   in
 
@@ -528,10 +526,10 @@ let export_types_group (fmt : Format.formatter) (config : gen_config)
     TODO: check correct behavior with opaque globals.
  *)
 let export_global (fmt : Format.formatter) (config : gen_config) (ctx : gen_ctx)
-    (id : A.GlobalDeclId.id) : unit =
+    (id : GlobalDeclId.id) : unit =
   let global_decls = ctx.trans_ctx.global_ctx.global_decls in
-  let global = A.GlobalDeclId.Map.find id global_decls in
-  let trans = A.FunDeclId.Map.find global.body_id ctx.trans_funs in
+  let global = GlobalDeclId.Map.find id global_decls in
+  let trans = FunDeclId.Map.find global.body ctx.trans_funs in
   assert (trans.fwd.loops = []);
   assert (trans.backs = []);
   let body = trans.fwd.f in
@@ -546,9 +544,9 @@ let export_global (fmt : Format.formatter) (config : gen_config) (ctx : gen_ctx)
   (* Check if it is a builtin global - if yes, we ignore it because we
      map the definition to one in the standard library *)
   let open ExtractBuiltin in
-  let sname = name_to_simple_name global.name in
   let extract =
-    extract && SimpleNameMap.find_opt sname builtin_globals_map = None
+    extract
+    && match_name_find_opt ctx.trans_ctx global.name builtin_globals_map = None
   in
   if extract then
     (* We don't wrap global declaration groups between calls to functions
@@ -662,8 +660,7 @@ let export_functions_group (fmt : Format.formatter) (config : gen_config)
     let funs_map = builtin_funs_map () in
     List.map
       (fun (trans : pure_fun_translation) ->
-        let sname = name_to_simple_name trans.fwd.f.basename in
-        SimpleNameMap.find_opt sname funs_map <> None)
+        match_name_find_opt ctx.trans_ctx trans.fwd.f.llbc_name funs_map <> None)
       pure_ls
   in
 
@@ -753,11 +750,14 @@ let export_functions_group (fmt : Format.formatter) (config : gen_config)
 let export_trait_decl (fmt : Format.formatter) (_config : gen_config)
     (ctx : gen_ctx) (trait_decl_id : Pure.trait_decl_id) (extract_decl : bool)
     (extract_extra_info : bool) : unit =
-  let trait_decl = T.TraitDeclId.Map.find trait_decl_id ctx.trans_trait_decls in
+  let trait_decl = TraitDeclId.Map.find trait_decl_id ctx.trans_trait_decls in
   (* Check if the trait declaration is builtin, in which case we ignore it *)
   let open ExtractBuiltin in
-  let sname = name_to_simple_name trait_decl.name in
-  if SimpleNameMap.find_opt sname (builtin_trait_decls_map ()) = None then (
+  if
+    match_name_find_opt ctx.trans_ctx trait_decl.llbc_name
+      (builtin_trait_decls_map ())
+    = None
+  then (
     let ctx = { ctx with trait_decl_id = Some trait_decl.def_id } in
     if extract_decl then Extract.extract_trait_decl ctx fmt trait_decl;
     if extract_extra_info then
@@ -768,7 +768,7 @@ let export_trait_decl (fmt : Format.formatter) (_config : gen_config)
 let export_trait_impl (fmt : Format.formatter) (_config : gen_config)
     (ctx : gen_ctx) (trait_impl_id : Pure.trait_impl_id) : unit =
   (* Lookup the definition *)
-  let trait_impl = T.TraitImplId.Map.find trait_impl_id ctx.trans_trait_impls in
+  let trait_impl = TraitImplId.Map.find trait_impl_id ctx.trans_trait_impls in
   let trait_decl =
     Pure.TraitDeclId.Map.find trait_impl.impl_trait.trait_decl_id
       ctx.trans_trait_decls
@@ -776,9 +776,11 @@ let export_trait_impl (fmt : Format.formatter) (_config : gen_config)
   (* Check if the trait implementation is builtin *)
   let builtin_info =
     let open ExtractBuiltin in
-    let type_sname = name_to_simple_name trait_impl.name in
-    let trait_sname = name_to_simple_name trait_decl.name in
-    SimpleNamePairMap.find_opt (type_sname, trait_sname)
+    let trait_impl =
+      TraitImplId.Map.find trait_impl.def_id ctx.crate.trait_impls
+    in
+    match_name_with_generics_find_opt ctx.trans_ctx trait_decl.llbc_name
+      trait_impl.impl_trait.decl_generics
       (builtin_trait_impls_map ())
   in
   match builtin_info with
@@ -814,14 +816,15 @@ let extract_definitions (fmt : Format.formatter) (config : gen_config)
     Extract.extract_state_type fmt ctx kind
   in
 
-  let export_decl_group (dg : A.declaration_group) : unit =
+  let export_decl_group (dg : declaration_group) : unit =
     match dg with
-    | Type (NonRec id) ->
+    | TypeGroup (NonRecGroup id) ->
         if config.extract_types then export_types_group false [ id ]
-    | Type (Rec ids) -> if config.extract_types then export_types_group true ids
-    | Fun (NonRec id) -> (
+    | TypeGroup (RecGroup ids) ->
+        if config.extract_types then export_types_group true ids
+    | FunGroup (NonRecGroup id) -> (
         (* Lookup *)
-        let pure_fun = A.FunDeclId.Map.find id ctx.trans_funs in
+        let pure_fun = FunDeclId.Map.find id ctx.trans_funs in
         (* Special case: we skip trait method *declarations* (we will
            extract their type directly in the records we generate for
            the trait declarations themselves, there is no point in having
@@ -831,21 +834,21 @@ let extract_definitions (fmt : Format.formatter) (config : gen_config)
         | _ ->
             (* Translate *)
             export_functions_group [ pure_fun ])
-    | Fun (Rec ids) ->
+    | FunGroup (RecGroup ids) ->
         (* General case of mutually recursive functions *)
         (* Lookup *)
         let pure_funs =
-          List.map (fun id -> A.FunDeclId.Map.find id ctx.trans_funs) ids
+          List.map (fun id -> FunDeclId.Map.find id ctx.trans_funs) ids
         in
         (* Translate *)
         export_functions_group pure_funs
-    | Global id -> export_global id
-    | TraitDecl id ->
+    | GlobalGroup id -> export_global id
+    | TraitDeclGroup id ->
         (* TODO: update to extract groups *)
         if config.extract_trait_decls && config.extract_transparent then (
           export_trait_decl_group id;
           export_trait_decl_group_extra_info id)
-    | TraitImpl id ->
+    | TraitImplGroup id ->
         if config.extract_trait_impls && config.extract_transparent then
           export_trait_impl id
   in
@@ -983,27 +986,17 @@ let extract_file (config : gen_config) (ctx : gen_ctx) (fi : extract_file_info)
   close_out out
 
 (** Translate a crate and write the synthesized code to an output file. *)
-let translate_crate (filename : string) (dest_dir : string) (crate : A.crate) :
+let translate_crate (filename : string) (dest_dir : string) (crate : crate) :
     unit =
   (* Translate the module to the pure AST *)
   let trans_ctx, trans_types, trans_funs, trans_trait_decls, trans_trait_impls =
     translate_crate_to_pure crate
   in
 
-  (* Initialize the extraction context - for now we extract only to F*.
-   * We initialize the names map by registering the keywords used in the
-   * language, as well as some primitive names ("u32", etc.) *)
-  let variant_concatenate_type_name =
-    (* For Lean, we exploit the fact that the variant name should always be
-       prefixed with the type name to prevent collisions *)
-    match !Config.backend with Coq | FStar | HOL4 -> true | Lean -> false
-  in
-  (* Initialize the names map (we insert the names of the "primitives"
-     declarations, and insert the names of the local declarations later) *)
-  let fmt, names_maps =
-    Extract.mk_formatter_and_names_maps trans_ctx crate.name
-      variant_concatenate_type_name
-  in
+  (* Initialize the names map by registering the keywords used in the
+     language, as well as some primitive names ("u32", etc.).
+     We insert the names of the local declarations later. *)
+  let names_maps = Extract.initialize_names_maps () in
 
   (* We need to compute which functions are recursive, in order to know
    * whether we should generate a decrease clause or not. *)
@@ -1033,8 +1026,8 @@ let translate_crate (filename : string) (dest_dir : string) (crate : A.crate) :
     Pure.TypeDeclId.Map.of_list
       (List.map (fun (d : Pure.type_decl) -> (d.def_id, d)) trans_types)
   in
-  let trans_funs : pure_fun_translation A.FunDeclId.Map.t =
-    A.FunDeclId.Map.of_list
+  let trans_funs : pure_fun_translation FunDeclId.Map.t =
+    FunDeclId.Map.of_list
       (List.map
          (fun (trans : pure_fun_translation) -> (trans.fwd.f.def_id, trans))
          trans_funs)
@@ -1043,13 +1036,13 @@ let translate_crate (filename : string) (dest_dir : string) (crate : A.crate) :
   (* Put everything in the context *)
   let ctx =
     let trans_trait_decls =
-      T.TraitDeclId.Map.of_list
+      TraitDeclId.Map.of_list
         (List.map
            (fun (d : Pure.trait_decl) -> (d.def_id, d))
            trans_trait_decls)
     in
     let trans_trait_impls =
-      T.TraitImplId.Map.of_list
+      TraitImplId.Map.of_list
         (List.map
            (fun (d : Pure.trait_impl) -> (d.def_id, d))
            trans_trait_impls)
@@ -1058,7 +1051,6 @@ let translate_crate (filename : string) (dest_dir : string) (crate : A.crate) :
       ExtractBase.crate;
       trans_ctx;
       names_maps;
-      fmt;
       indent_incr = 2;
       use_dep_ite = !Config.backend = Lean && !Config.extract_decreases_clauses;
       fun_name_info = PureUtils.RegularFunIdMap.empty;
@@ -1104,12 +1096,12 @@ let translate_crate (filename : string) (dest_dir : string) (crate : A.crate) :
         if is_global then ctx
         else Extract.extract_fun_decl_register_names ctx gen_decr_clause trans)
       ctx
-      (A.FunDeclId.Map.values trans_funs)
+      (FunDeclId.Map.values trans_funs)
   in
 
   let ctx =
     List.fold_left Extract.extract_global_decl_register_names ctx
-      (A.GlobalDeclId.Map.values crate.globals)
+      (GlobalDeclId.Map.values crate.global_decls)
   in
 
   let ctx =
@@ -1288,7 +1280,7 @@ let translate_crate (filename : string) (dest_dir : string) (crate : A.crate) :
          namespace;
          in_namespace = true;
          crate_name;
-         rust_module_name = crate.A.name;
+         rust_module_name = crate.name;
          module_name = types_module;
          custom_msg = ": type definitions";
          custom_imports = [];
@@ -1316,7 +1308,7 @@ let translate_crate (filename : string) (dest_dir : string) (crate : A.crate) :
             namespace;
             in_namespace = true;
             crate_name;
-            rust_module_name = crate.A.name;
+            rust_module_name = crate.name;
             module_name = template_clauses_module;
             custom_msg = ": templates for the decreases clauses";
             custom_imports = [ types_module ];
@@ -1366,7 +1358,7 @@ let translate_crate (filename : string) (dest_dir : string) (crate : A.crate) :
              namespace;
              in_namespace = false;
              crate_name;
-             rust_module_name = crate.A.name;
+             rust_module_name = crate.name;
              module_name = opaque_module;
              custom_msg;
              custom_imports = [];
@@ -1405,7 +1397,7 @@ let translate_crate (filename : string) (dest_dir : string) (crate : A.crate) :
          namespace;
          in_namespace = true;
          crate_name;
-         rust_module_name = crate.A.name;
+         rust_module_name = crate.name;
          module_name = fun_module;
          custom_msg = ": function definitions";
          custom_imports = [];
@@ -1438,7 +1430,7 @@ let translate_crate (filename : string) (dest_dir : string) (crate : A.crate) :
          namespace;
          in_namespace = true;
          crate_name;
-         rust_module_name = crate.A.name;
+         rust_module_name = crate.name;
          module_name = crate_name;
          custom_msg = "";
          custom_imports = [];
diff --git a/compiler/TranslateCore.ml b/compiler/TranslateCore.ml
index 3427fd43..abf4fcf7 100644
--- a/compiler/TranslateCore.ml
+++ b/compiler/TranslateCore.ml
@@ -1,16 +1,12 @@
 (** Some utilities for the translation *)
 
-open InterpreterStatements
-module L = Logging
-module T = Types
-module A = LlbcAst
-module SA = SymbolicAst
-module FA = FunsAnalysis
+open Contexts
+open ExtractName
 
 (** The local logger *)
-let log = L.translate_log
+let log = Logging.translate_log
 
-type trans_ctx = C.decls_ctx [@@deriving show]
+type trans_ctx = decls_ctx [@@deriving show]
 type fun_and_loops = { f : Pure.fun_decl; loops : Pure.fun_decl list }
 type pure_fun_translation_no_loops = Pure.fun_decl * Pure.fun_decl list
 
@@ -26,53 +22,61 @@ type pure_fun_translation = {
   backs : fun_and_loops list;
 }
 
-let trans_ctx_to_type_formatter (ctx : trans_ctx)
-    (type_params : Pure.type_var list)
-    (const_generic_params : Pure.const_generic_var list) :
-    PrintPure.type_formatter =
-  let type_decls = ctx.type_ctx.type_decls in
-  let global_decls = ctx.global_ctx.global_decls in
-  let trait_decls = ctx.trait_decls_ctx.trait_decls in
-  let trait_impls = ctx.trait_impls_ctx.trait_impls in
-  PrintPure.mk_type_formatter type_decls global_decls trait_decls trait_impls
-    type_params const_generic_params
+let trans_ctx_to_fmt_env (ctx : trans_ctx) : Print.fmt_env =
+  Print.Contexts.decls_ctx_to_fmt_env ctx
 
-let type_decl_to_string (ctx : trans_ctx) (def : Pure.type_decl) : string =
-  let generics = def.generics in
-  let fmt =
-    trans_ctx_to_type_formatter ctx generics.types generics.const_generics
-  in
-  PrintPure.type_decl_to_string fmt def
+let trans_ctx_to_pure_fmt_env (ctx : trans_ctx) : PrintPure.fmt_env =
+  PrintPure.decls_ctx_to_fmt_env ctx
 
-let type_id_to_string (ctx : trans_ctx) (id : Pure.TypeDeclId.id) : string =
-  Print.fun_name_to_string
-    (Pure.TypeDeclId.Map.find id ctx.type_ctx.type_decls).name
+let name_to_string (ctx : trans_ctx) =
+  Print.Types.name_to_string (trans_ctx_to_fmt_env ctx)
 
-let trans_ctx_to_ast_formatter (ctx : trans_ctx)
-    (type_params : Pure.type_var list)
-    (const_generic_params : Pure.const_generic_var list) :
-    PrintPure.ast_formatter =
-  let type_decls = ctx.type_ctx.type_decls in
-  let fun_decls = ctx.fun_ctx.fun_decls in
-  let global_decls = ctx.global_ctx.global_decls in
-  let trait_decls = ctx.trait_decls_ctx.trait_decls in
-  let trait_impls = ctx.trait_impls_ctx.trait_impls in
-  PrintPure.mk_ast_formatter type_decls fun_decls global_decls trait_decls
-    trait_impls type_params const_generic_params
+let match_name_find_opt (ctx : trans_ctx) (name : Types.name)
+    (m : 'a NameMatcherMap.t) : 'a option =
+  let open Charon.NameMatcher in
+  let open ExtractBuiltin in
+  let mctx : ctx =
+    {
+      type_decls = ctx.type_ctx.type_decls;
+      global_decls = ctx.global_ctx.global_decls;
+      trait_decls = ctx.trait_decls_ctx.trait_decls;
+    }
+  in
+  NameMatcherMap.find_opt mctx name m
 
-let fun_sig_to_string (ctx : trans_ctx) (sg : Pure.fun_sig) : string =
-  let generics = sg.generics in
-  let fmt =
-    trans_ctx_to_ast_formatter ctx generics.types generics.const_generics
+let match_name_with_generics_find_opt (ctx : trans_ctx) (name : Types.name)
+    (generics : Types.generic_args) (m : 'a NameMatcherMap.t) : 'a option =
+  let open Charon.NameMatcher in
+  let open ExtractBuiltin in
+  let mctx : ctx =
+    {
+      type_decls = ctx.type_ctx.type_decls;
+      global_decls = ctx.global_ctx.global_decls;
+      trait_decls = ctx.trait_decls_ctx.trait_decls;
+    }
   in
-  PrintPure.fun_sig_to_string fmt sg
+  NameMatcherMap.find_with_generics_opt mctx name generics m
 
-let fun_decl_to_string (ctx : trans_ctx) (def : Pure.fun_decl) : string =
-  let generics = def.signature.generics in
-  let fmt =
-    trans_ctx_to_ast_formatter ctx generics.types generics.const_generics
+let name_to_simple_name (ctx : trans_ctx) (n : Types.name) : string list =
+  let mctx : Charon.NameMatcher.ctx =
+    {
+      type_decls = ctx.type_ctx.type_decls;
+      global_decls = ctx.global_ctx.global_decls;
+      trait_decls = ctx.trait_decls_ctx.trait_decls;
+    }
   in
-  PrintPure.fun_decl_to_string fmt def
+  let is_trait_impl = false in
+  name_to_simple_name mctx is_trait_impl n
 
-let fun_decl_id_to_string (ctx : trans_ctx) (id : A.FunDeclId.id) : string =
-  Print.fun_name_to_string (A.FunDeclId.Map.find id ctx.fun_ctx.fun_decls).name
+let trait_name_with_generics_to_simple_name (ctx : trans_ctx)
+    ?(prefix : Types.name option = None) (n : Types.name)
+    (p : Types.generic_params) (g : Types.generic_args) : string list =
+  let mctx : Charon.NameMatcher.ctx =
+    {
+      type_decls = ctx.type_ctx.type_decls;
+      global_decls = ctx.global_ctx.global_decls;
+      trait_decls = ctx.trait_decls_ctx.trait_decls;
+    }
+  in
+  let is_trait_impl = true in
+  name_with_generics_to_simple_name mctx is_trait_impl ~prefix n p g
diff --git a/compiler/TypesAnalysis.ml b/compiler/TypesAnalysis.ml
index 38d350b1..eb0aeea9 100644
--- a/compiler/TypesAnalysis.ml
+++ b/compiler/TypesAnalysis.ml
@@ -1,5 +1,5 @@
 open Types
-module A = LlbcAst
+open LlbcAst
 
 type subtype_info = {
   under_borrow : bool;  (** Are we inside a borrow? *)
@@ -77,9 +77,8 @@ let partial_type_info_to_type_decl_info (info : partial_type_info) :
 let partial_type_info_to_ty_info (info : partial_type_info) : ty_info =
   info.borrows_info
 
-let analyze_full_ty (r_is_static : 'r -> bool) (updated : bool ref)
-    (infos : type_infos) (ty_info : partial_type_info) (ty : 'r ty) :
-    partial_type_info =
+let analyze_full_ty (updated : bool ref) (infos : type_infos)
+    (ty_info : partial_type_info) (ty : ty) : partial_type_info =
   (* Small utility *)
   let check_update_bool (original : bool) (nv : bool) : bool =
     if nv && not original then (
@@ -87,6 +86,7 @@ let analyze_full_ty (r_is_static : 'r -> bool) (updated : bool ref)
       nv)
     else original
   in
+  let r_is_static (r : region) : bool = r = RStatic in
 
   (* Update a partial_type_info, while registering if we actually performed an update *)
   let update_ty_info (ty_info : partial_type_info)
@@ -119,10 +119,10 @@ let analyze_full_ty (r_is_static : 'r -> bool) (updated : bool ref)
 
   (* The recursive function which explores the type *)
   let rec analyze (expl_info : expl_info) (ty_info : partial_type_info)
-      (ty : 'r ty) : partial_type_info =
+      (ty : ty) : partial_type_info =
     match ty with
-    | Literal _ | Never | TraitType _ -> ty_info
-    | TypeVar var_id -> (
+    | TLiteral _ | TNever | TTraitType _ -> ty_info
+    | TVar var_id -> (
         (* Update the information for the proper parameter, if necessary *)
         match ty_info.param_infos with
         | None -> ty_info
@@ -144,7 +144,7 @@ let analyze_full_ty (r_is_static : 'r -> bool) (updated : bool ref)
             in
             let param_infos = Some param_infos in
             { ty_info with param_infos })
-    | Ref (r, rty, rkind) ->
+    | TRef (r, rty, rkind) ->
         (* Update the type info *)
         let contains_static = r_is_static r in
         let contains_borrow = true in
@@ -163,20 +163,20 @@ let analyze_full_ty (r_is_static : 'r -> bool) (updated : bool ref)
         let expl_info =
           {
             under_borrow = true;
-            under_mut_borrow = expl_info.under_mut_borrow || rkind = Mut;
+            under_mut_borrow = expl_info.under_mut_borrow || rkind = RMut;
           }
         in
         (* Continue exploring *)
         analyze expl_info ty_info rty
-    | RawPtr (rty, _) ->
+    | TRawPtr (rty, _) ->
         (* TODO: not sure what to do here *)
         analyze expl_info ty_info rty
-    | Adt ((Tuple | Assumed (Box | Slice | Array | Str)), generics) ->
+    | TAdt ((TTuple | TAssumed (TBox | TSlice | TArray | TStr)), generics) ->
         (* Nothing to update: just explore the type parameters *)
         List.fold_left
           (fun ty_info ty -> analyze expl_info ty_info ty)
           ty_info generics.types
-    | Adt (AdtId adt_id, generics) ->
+    | TAdt (TAdtId adt_id, generics) ->
         (* Lookup the information for this type definition *)
         let adt_info = TypeDeclId.Map.find adt_id infos in
         (* Update the type info with the information from the adt *)
@@ -233,7 +233,7 @@ let analyze_full_ty (r_is_static : 'r -> bool) (updated : bool ref)
         in
         (* Return *)
         ty_info
-    | Arrow (inputs, output) ->
+    | TArrow (inputs, output) ->
         (* Just dive into the arrow *)
         let ty_info =
           List.fold_left
@@ -255,7 +255,7 @@ let analyze_type_decl (updated : bool ref) (infos : type_infos)
   if type_decl_is_opaque def then infos
   else
     (* Retrieve all the types of all the fields of all the variants *)
-    let fields_tys : sty list =
+    let fields_tys : ty list =
       match def.kind with
       | Struct fields -> List.map (fun f -> f.field_ty) fields
       | Enum variants ->
@@ -266,13 +266,12 @@ let analyze_type_decl (updated : bool ref) (infos : type_infos)
       | Opaque -> raise (Failure "unreachable")
     in
     (* Explore the types and accumulate information *)
-    let r_is_static r = r = Static in
     let type_decl_info = TypeDeclId.Map.find def.def_id infos in
     let type_decl_info = type_decl_info_to_partial_type_info type_decl_info in
     let type_decl_info =
       List.fold_left
         (fun type_decl_info ty ->
-          analyze_full_ty r_is_static updated infos type_decl_info ty)
+          analyze_full_ty updated infos type_decl_info ty)
         type_decl_info fields_tys
     in
     let type_decl_info = partial_type_info_to_type_decl_info type_decl_info in
@@ -282,15 +281,15 @@ let analyze_type_decl (updated : bool ref) (infos : type_infos)
     infos
 
 let analyze_type_declaration_group (type_decls : type_decl TypeDeclId.Map.t)
-    (infos : type_infos) (decl : A.type_declaration_group) : type_infos =
+    (infos : type_infos) (decl : type_declaration_group) : type_infos =
   (* Collect the identifiers used in the declaration group *)
-  let ids = match decl with NonRec id -> [ id ] | Rec ids -> ids in
+  let ids = match decl with NonRecGroup id -> [ id ] | RecGroup ids -> ids in
   (* Retrieve the type definitions *)
   let decl_defs = List.map (fun id -> TypeDeclId.Map.find id type_decls) ids in
   (* Initialize the type information for the current definitions *)
   let infos =
     List.fold_left
-      (fun infos def ->
+      (fun infos (def : type_decl) ->
         TypeDeclId.Map.add def.def_id (initialize_type_decl_info def) infos)
       infos decl_defs
   in
@@ -316,7 +315,7 @@ let analyze_type_declaration_group (type_decls : type_decl TypeDeclId.Map.t)
     Rk.: pay attention to the difference between type definitions and types!
  *)
 let analyze_type_declarations (type_decls : type_decl TypeDeclId.Map.t)
-    (decls : A.type_declaration_group list) : type_infos =
+    (decls : type_declaration_group list) : type_infos =
   List.fold_left
     (fun infos decl -> analyze_type_declaration_group type_decls infos decl)
     TypeDeclId.Map.empty decls
@@ -324,12 +323,11 @@ let analyze_type_declarations (type_decls : type_decl TypeDeclId.Map.t)
 (** Analyze a type to check whether it contains borrows, etc., provided
     we have already analyzed the type definitions in the context.
  *)
-let analyze_ty (infos : type_infos) (ty : 'r ty) : ty_info =
+let analyze_ty (infos : type_infos) (ty : ty) : ty_info =
   (* We don't use [updated] but need to give it as parameter *)
   let updated = ref false in
   (* We don't need to compute whether the type contains 'static or not *)
-  let r_is_static _ = false in
   let ty_info = initialize_g_type_info None in
-  let ty_info = analyze_full_ty r_is_static updated infos ty_info ty in
+  let ty_info = analyze_full_ty updated infos ty_info ty in
   (* Convert the ty_info *)
   partial_type_info_to_ty_info ty_info
diff --git a/compiler/TypesUtils.ml b/compiler/TypesUtils.ml
index c7f0fbc3..52e12b9a 100644
--- a/compiler/TypesUtils.ml
+++ b/compiler/TypesUtils.ml
@@ -1,6 +1,6 @@
 open Types
+open Utils
 include Charon.TypesUtils
-module TA = TypesAnalysis
 
 (** Retuns true if the type contains borrows.
 
@@ -8,9 +8,9 @@ module TA = TypesAnalysis
     we erase the lists of regions (by replacing them with [[]] when using {!Types.ety},
     and when a type uses 'static this region doesn't appear in the region parameters.
  *)
-let ty_has_borrows (infos : TA.type_infos) (ty : 'r ty) : bool =
-  let info = TA.analyze_ty infos ty in
-  info.TA.contains_borrow
+let ty_has_borrows (infos : TypesAnalysis.type_infos) (ty : ty) : bool =
+  let info = TypesAnalysis.analyze_ty infos ty in
+  info.TypesAnalysis.contains_borrow
 
 (** Retuns true if the type contains nested borrows.
 
@@ -18,11 +18,92 @@ let ty_has_borrows (infos : TA.type_infos) (ty : 'r ty) : bool =
     we erase the lists of regions (by replacing them with [[]] when using {!Types.ety},
     and when a type uses 'static this region doesn't appear in the region parameters.
  *)
-let ty_has_nested_borrows (infos : TA.type_infos) (ty : 'r ty) : bool =
-  let info = TA.analyze_ty infos ty in
-  info.TA.contains_nested_borrows
+let ty_has_nested_borrows (infos : TypesAnalysis.type_infos) (ty : ty) : bool =
+  let info = TypesAnalysis.analyze_ty infos ty in
+  info.TypesAnalysis.contains_nested_borrows
 
 (** Retuns true if the type contains a borrow under a mutable borrow *)
-let ty_has_borrow_under_mut (infos : TA.type_infos) (ty : 'r ty) : bool =
-  let info = TA.analyze_ty infos ty in
-  info.TA.contains_borrow_under_mut
+let ty_has_borrow_under_mut (infos : TypesAnalysis.type_infos) (ty : ty) : bool
+    =
+  let info = TypesAnalysis.analyze_ty infos ty in
+  info.TypesAnalysis.contains_borrow_under_mut
+
+(** Small helper *)
+let raise_if_erased_ty_visitor =
+  object
+    inherit [_] iter_ty
+    method! visit_RErased _ = raise Found
+  end
+
+(** Return [true] if the type is a region type (i.e., it doesn't contain erased regions) *)
+let ty_is_rty (ty : ty) : bool =
+  try
+    raise_if_erased_ty_visitor#visit_ty () ty;
+    true
+  with Found -> false
+
+(** Small helper *)
+let raise_if_not_erased_ty_visitor =
+  object
+    inherit [_] iter_ty
+    method! visit_RStatic _ = raise Found
+    method! visit_RVar _ = raise Found
+  end
+
+(** Return [true] if the type is a region type (i.e., it doesn't contain erased regions) *)
+let ty_is_ety (ty : ty) : bool =
+  try
+    raise_if_not_erased_ty_visitor#visit_ty () ty;
+    true
+  with Found -> false
+
+let generic_args_only_erased_regions (x : generic_args) : bool =
+  try
+    raise_if_not_erased_ty_visitor#visit_generic_args () x;
+    true
+  with Found -> false
+
+(** Small helper *)
+let raise_if_region_ty_visitor =
+  object
+    inherit [_] iter_ty
+    method! visit_region _ _ = raise Found
+  end
+
+(** Return [true] if the type doesn't contain regions (including erased regions) *)
+let ty_no_regions (ty : ty) : bool =
+  try
+    raise_if_region_ty_visitor#visit_ty () ty;
+    true
+  with Found -> false
+
+(** Return [true] if the trait ref doesn't contain regions (including erased regions) *)
+let trait_ref_no_regions (x : trait_ref) : bool =
+  try
+    raise_if_region_ty_visitor#visit_trait_ref () x;
+    true
+  with Found -> false
+
+(** Return [true] if the trait instance id doesn't contain regions (including erased regions) *)
+let trait_instance_id_no_regions (x : trait_instance_id) : bool =
+  try
+    raise_if_region_ty_visitor#visit_trait_instance_id () x;
+    true
+  with Found -> false
+
+(** Return [true] if the generic args don't contain regions (including erased regions) *)
+let generic_args_no_regions (x : generic_args) : bool =
+  try
+    raise_if_region_ty_visitor#visit_generic_args () x;
+    true
+  with Found -> false
+
+(** Return [true] if the trait type constraint doesn't contain regions (including erased regions) *)
+let trait_type_constraint_no_regions (x : trait_type_constraint) : bool =
+  try
+    let { trait_ref; generics; type_name = _; ty } = x in
+    raise_if_region_ty_visitor#visit_trait_ref () trait_ref;
+    raise_if_region_ty_visitor#visit_generic_args () generics;
+    raise_if_region_ty_visitor#visit_ty () ty;
+    true
+  with Found -> false
diff --git a/compiler/Values.ml b/compiler/Values.ml
index de27e7a9..c1ff9804 100644
--- a/compiler/Values.ml
+++ b/compiler/Values.ml
@@ -1,6 +1,6 @@
 open Identifiers
 open Types
-module PrimitiveValues = PrimitiveValues
+include Charon.Values
 
 (* TODO(SH): I often write "abstract" (value, borrow content, etc.) while I should
  * write "abstraction" (because those values are not abstract, they simply are
@@ -12,9 +12,6 @@ module AbstractionId = IdGen ()
 module FunCallId = IdGen ()
 module LoopId = IdGen ()
 
-type big_int = PrimitiveValues.big_int [@@deriving show, ord]
-type scalar_value = PrimitiveValues.scalar_value [@@deriving show, ord]
-type literal = PrimitiveValues.literal [@@deriving show, ord]
 type symbolic_value_id = SymbolicValueId.id [@@deriving show, ord]
 type symbolic_value_id_set = SymbolicValueId.Set.t [@@deriving show, ord]
 type loop_id = LoopId.id [@@deriving show, ord]
@@ -58,55 +55,6 @@ type sv_kind =
       (** A symbolic value we introduce when evaluating a trait associated constant *)
 [@@deriving show, ord]
 
-(** Ancestor for {!symbolic_value} iter visitor *)
-class ['self] iter_symbolic_value_base =
-  object (_self : 'self)
-    inherit [_] VisitorsRuntime.iter
-    method visit_sv_kind : 'env -> sv_kind -> unit = fun _ _ -> ()
-    method visit_rty : 'env -> rty -> unit = fun _ _ -> ()
-
-    method visit_symbolic_value_id : 'env -> symbolic_value_id -> unit =
-      fun _ _ -> ()
-  end
-
-(** Ancestor for {!symbolic_value} map visitor for *)
-class ['self] map_symbolic_value_base =
-  object (_self : 'self)
-    inherit [_] VisitorsRuntime.map
-    method visit_sv_kind : 'env -> sv_kind -> sv_kind = fun _ x -> x
-    method visit_rty : 'env -> rty -> rty = fun _ x -> x
-
-    method visit_symbolic_value_id
-        : 'env -> symbolic_value_id -> symbolic_value_id =
-      fun _ x -> x
-  end
-
-(** A symbolic value *)
-type symbolic_value = {
-  sv_kind : sv_kind;
-  sv_id : symbolic_value_id;
-  sv_ty : rty;
-}
-[@@deriving
-  show,
-    ord,
-    visitors
-      {
-        name = "iter_symbolic_value";
-        variety = "iter";
-        ancestors = [ "iter_symbolic_value_base" ];
-        nude = true (* Don't inherit {!VisitorsRuntime.iter} *);
-        concrete = true;
-      },
-    visitors
-      {
-        name = "map_symbolic_value";
-        variety = "map";
-        ancestors = [ "map_symbolic_value_base" ];
-        nude = true (* Don't inherit {!VisitorsRuntime.iter} *);
-        concrete = true;
-      }]
-
 type borrow_id = BorrowId.id [@@deriving show, ord]
 type borrow_id_set = BorrowId.Set.t [@@deriving show, ord]
 type loan_id = BorrowId.id [@@deriving show, ord]
@@ -115,11 +63,13 @@ type loan_id_set = BorrowId.Set.t [@@deriving show, ord]
 (** Ancestor for {!typed_value} iter visitor *)
 class ['self] iter_typed_value_base =
   object (self : 'self)
-    inherit [_] iter_symbolic_value
-    method visit_literal : 'env -> literal -> unit = fun _ _ -> ()
-    method visit_erased_region : 'env -> erased_region -> unit = fun _ _ -> ()
+    inherit [_] iter_ty
+    method visit_sv_kind : 'env -> sv_kind -> unit = fun _ _ -> ()
+
+    method visit_symbolic_value_id : 'env -> symbolic_value_id -> unit =
+      fun _ _ -> ()
+
     method visit_variant_id : 'env -> variant_id -> unit = fun _ _ -> ()
-    method visit_ety : 'env -> ety -> unit = fun _ _ -> ()
     method visit_borrow_id : 'env -> borrow_id -> unit = fun _ _ -> ()
     method visit_loan_id : 'env -> loan_id -> unit = fun _ _ -> ()
 
@@ -133,13 +83,13 @@ class ['self] iter_typed_value_base =
 (** Ancestor for {!typed_value} map visitor for *)
 class ['self] map_typed_value_base =
   object (self : 'self)
-    inherit [_] map_symbolic_value
-    method visit_literal : 'env -> literal -> literal = fun _ cv -> cv
+    inherit [_] map_ty
+    method visit_sv_kind : 'env -> sv_kind -> sv_kind = fun _ x -> x
 
-    method visit_erased_region : 'env -> erased_region -> erased_region =
-      fun _ r -> r
+    method visit_symbolic_value_id
+        : 'env -> symbolic_value_id -> symbolic_value_id =
+      fun _ x -> x
 
-    method visit_ety : 'env -> ety -> ety = fun _ ty -> ty
     method visit_variant_id : 'env -> variant_id -> variant_id = fun _ x -> x
     method visit_borrow_id : 'env -> borrow_id -> borrow_id = fun _ id -> id
     method visit_loan_id : 'env -> loan_id -> loan_id = fun _ id -> id
@@ -151,14 +101,21 @@ class ['self] map_typed_value_base =
       fun env ids -> BorrowId.Set.map (self#visit_loan_id env) ids
   end
 
-(** An untyped value, used in the environments *)
-type value =
-  | Literal of literal  (** Non-symbolic primitive value *)
-  | Adt of adt_value  (** Enumerations and structures *)
-  | Bottom  (** No value (uninitialized or moved value) *)
-  | Borrow of borrow_content  (** A borrowed value *)
-  | Loan of loan_content  (** A loaned value *)
-  | Symbolic of symbolic_value
+(** A symbolic value *)
+type symbolic_value = {
+  sv_kind : sv_kind;
+  sv_id : symbolic_value_id;
+  sv_ty : ty;  (** This should be a type with regions *)
+}
+
+(** An untyped value, used in the environments - TODO: prefix the names with "V" *)
+and value =
+  | VLiteral of literal  (** Non-symbolic primitive value *)
+  | VAdt of adt_value  (** Enumerations and structures *)
+  | VBottom  (** No value (uninitialized or moved value) *)
+  | VBorrow of borrow_content  (** A borrowed value *)
+  | VLoan of loan_content  (** A loaned value *)
+  | VSymbolic of symbolic_value
       (** Borrow projector over a symbolic value.
       
           Note that contrary to the abstraction-values case, symbolic values
@@ -172,9 +129,9 @@ and adt_value = {
 }
 
 and borrow_content =
-  | SharedBorrow of borrow_id  (** A shared borrow. *)
-  | MutBorrow of borrow_id * typed_value  (** A mutably borrowed value. *)
-  | ReservedMutBorrow of borrow_id
+  | VSharedBorrow of borrow_id  (** A shared borrow. *)
+  | VMutBorrow of borrow_id * typed_value  (** A mutably borrowed value. *)
+  | VReservedMutBorrow of borrow_id
       (** A reserved mut borrow.
 
           This is used to model {{: https://rustc-dev-guide.rust-lang.org/borrow_check/two_phase_borrows.html} two-phase borrows}.
@@ -212,28 +169,17 @@ and borrow_content =
        *)
 
 and loan_content =
-  | SharedLoan of loan_id_set * typed_value
-  | MutLoan of loan_id
-
-(** "Meta"-value: information we store for the synthesis.
-
-     Note that we never automatically visit the meta-values with the
-     visitors: they really are meta information, and shouldn't be considered
-     as part of the environment during a symbolic execution.
-     
-     TODO: we may want to create wrappers, to prevent accidently mixing meta
-     values and regular values.
- *)
-and mvalue = typed_value
+  | VSharedLoan of loan_id_set * typed_value
+  | VMutLoan of loan_id
 
 (** "Regular" typed value (we map variables to typed values) *)
-and typed_value = { value : value; ty : ety }
+and typed_value = { value : value; ty : ty }
 [@@deriving
   show,
     ord,
     visitors
       {
-        name = "iter_typed_value_visit_mvalue";
+        name = "iter_typed_value";
         variety = "iter";
         ancestors = [ "iter_typed_value_base" ];
         nude = true (* Don't inherit {!VisitorsRuntime.iter} *);
@@ -241,13 +187,24 @@ and typed_value = { value : value; ty : ety }
       },
     visitors
       {
-        name = "map_typed_value_visit_mvalue";
+        name = "map_typed_value";
         variety = "map";
         ancestors = [ "map_typed_value_base" ];
         nude = true (* Don't inherit {!VisitorsRuntime.iter} *);
         concrete = true;
       }]
 
+(** "Meta"-value: information we store for the synthesis.
+
+     Note that we never automatically visit the meta-values with the
+     visitors: they really are meta information, and shouldn't be considered
+     as part of the environment during a symbolic execution.
+
+     TODO: we may want to create wrappers, to prevent accidently mixing meta
+     values and regular values.
+ *)
+type mvalue = typed_value [@@deriving show, ord]
+
 (** "Meta"-symbolic value.
 
      See the explanations for {!mvalue}
@@ -257,28 +214,47 @@ and typed_value = { value : value; ty : ety }
  *)
 type msymbolic_value = symbolic_value [@@deriving show, ord]
 
-class ['self] iter_typed_value =
-  object (_self : 'self)
-    inherit [_] iter_typed_value_visit_mvalue
+type region_id = RegionId.id [@@deriving show, ord]
+type region_id_set = RegionId.Set.t [@@deriving show, ord]
+type abstraction_id = AbstractionId.id [@@deriving show, ord]
+type abstraction_id_set = AbstractionId.Set.t [@@deriving show, ord]
 
-    (** We have to override the {!iter_typed_value_visit_mvalue.visit_mvalue} method,
-        to ignore meta-values *)
-    method! visit_mvalue : 'env -> mvalue -> unit = fun _ _ -> ()
+(** Ancestor for {!typed_avalue} iter visitor *)
+class ['self] iter_typed_avalue_base =
+  object (self : 'self)
+    inherit [_] iter_typed_value
+    method visit_mvalue : 'env -> mvalue -> unit = fun _ _ -> ()
 
     method visit_msymbolic_value : 'env -> msymbolic_value -> unit =
       fun _ _ -> ()
-  end
 
-class ['self] map_typed_value =
-  object (_self : 'self)
-    inherit [_] map_typed_value_visit_mvalue
+    method visit_region_id_set : 'env -> region_id_set -> unit =
+      fun env ids -> RegionId.Set.iter (self#visit_region_id env) ids
+
+    method visit_abstraction_id : 'env -> abstraction_id -> unit = fun _ _ -> ()
 
-    (** We have to override the {!iter_typed_value_visit_mvalue.visit_mvalue} method,
-        to ignore meta-values *)
-    method! visit_mvalue : 'env -> mvalue -> mvalue = fun _ x -> x
+    method visit_abstraction_id_set : 'env -> abstraction_id_set -> unit =
+      fun env ids -> AbstractionId.Set.iter (self#visit_abstraction_id env) ids
+  end
+
+(** Ancestor for {!typed_avalue} map visitor *)
+class ['self] map_typed_avalue_base =
+  object (self : 'self)
+    inherit [_] map_typed_value
+    method visit_mvalue : 'env -> mvalue -> mvalue = fun _ x -> x
 
     method visit_msymbolic_value : 'env -> msymbolic_value -> msymbolic_value =
       fun _ m -> m
+
+    method visit_region_id_set : 'env -> region_id_set -> region_id_set =
+      fun env ids -> RegionId.Set.map (self#visit_region_id env) ids
+
+    method visit_abstraction_id : 'env -> abstraction_id -> abstraction_id =
+      fun _ x -> x
+
+    method visit_abstraction_id_set
+        : 'env -> abstraction_id_set -> abstraction_id_set =
+      fun env ids -> AbstractionId.Set.map (self#visit_abstraction_id env) ids
   end
 
 (** When giving shared borrows to functions (i.e., inserting shared borrows inside
@@ -297,62 +273,12 @@ class ['self] map_typed_value =
 *)
 type abstract_shared_borrow =
   | AsbBorrow of borrow_id
-  | AsbProjReborrows of symbolic_value * rty
-[@@deriving
-  show,
-    ord,
-    visitors
-      {
-        name = "iter_abstract_shared_borrow";
-        variety = "iter";
-        ancestors = [ "iter_typed_value" ];
-        nude = true (* Don't inherit {!VisitorsRuntime.iter} *);
-        concrete = true;
-      },
-    visitors
-      {
-        name = "map_abstract_shared_borrow";
-        variety = "map";
-        ancestors = [ "map_typed_value" ];
-        nude = true (* Don't inherit {!VisitorsRuntime.iter} *);
-        concrete = true;
-      }]
+  | AsbProjReborrows of symbolic_value * ty
 
 (** A set of abstract shared borrows *)
-type abstract_shared_borrows = abstract_shared_borrow list
-[@@deriving
-  show,
-    ord,
-    visitors
-      {
-        name = "iter_abstract_shared_borrows";
-        variety = "iter";
-        ancestors = [ "iter_abstract_shared_borrow" ];
-        nude = true (* Don't inherit {!VisitorsRuntime.iter} *);
-        concrete = true;
-      },
-    visitors
-      {
-        name = "map_abstract_shared_borrows";
-        variety = "map";
-        ancestors = [ "map_abstract_shared_borrow" ];
-        nude = true (* Don't inherit {!VisitorsRuntime.iter} *);
-        concrete = true;
-      }]
-
-(** Ancestor for {!aproj} iter visitor *)
-class ['self] iter_aproj_base =
-  object (_self : 'self)
-    inherit [_] iter_abstract_shared_borrows
-  end
-
-(** Ancestor for {!aproj} map visitor *)
-class ['self] map_aproj_base =
-  object (_self : 'self)
-    inherit [_] map_abstract_shared_borrows
-  end
+and abstract_shared_borrows = abstract_shared_borrow list
 
-type aproj =
+and aproj =
   | AProjLoans of symbolic_value * (msymbolic_value * aproj) list
       (** A projector of loans over a symbolic value.
       
@@ -393,7 +319,7 @@ type aproj =
           anywhere in the context below a projector of borrows which intersects
           this projector of loans.
        *)
-  | AProjBorrows of symbolic_value * rty
+  | AProjBorrows of symbolic_value * ty
       (** Note that an AProjBorrows only operates on a value which is not below
           a shared loan: under a shared loan, we use {!abstract_shared_borrow}.
           
@@ -414,82 +340,6 @@ type aproj =
           ending the borrow.
        *)
   | AIgnoredProjBorrows
-[@@deriving
-  show,
-    ord,
-    visitors
-      {
-        name = "iter_aproj";
-        variety = "iter";
-        ancestors = [ "iter_aproj_base" ];
-        nude = true (* Don't inherit {!VisitorsRuntime.iter} *);
-        concrete = true;
-      },
-    visitors
-      {
-        name = "map_aproj";
-        variety = "map";
-        ancestors = [ "map_aproj_base" ];
-        nude = true (* Don't inherit {!VisitorsRuntime.iter} *);
-        concrete = true;
-      }]
-
-type region = RegionVarId.id Types.region [@@deriving show, ord]
-type region_var_id = RegionVarId.id [@@deriving show, ord]
-type region_id = RegionId.id [@@deriving show, ord]
-type region_id_set = RegionId.Set.t [@@deriving show, ord]
-type abstraction_id = AbstractionId.id [@@deriving show, ord]
-type abstraction_id_set = AbstractionId.Set.t [@@deriving show, ord]
-
-(** Ancestor for {!typed_avalue} iter visitor *)
-class ['self] iter_typed_avalue_base =
-  object (self : 'self)
-    inherit [_] iter_aproj
-    method visit_region_var_id : 'env -> region_var_id -> unit = fun _ _ -> ()
-
-    method visit_region : 'env -> region -> unit =
-      fun env r ->
-        match r with
-        | Static -> ()
-        | Var rid -> self#visit_region_var_id env rid
-
-    method visit_region_id : 'env -> region_id -> unit = fun _ _ -> ()
-
-    method visit_region_id_set : 'env -> region_id_set -> unit =
-      fun env ids -> RegionId.Set.iter (self#visit_region_id env) ids
-
-    method visit_abstraction_id : 'env -> abstraction_id -> unit = fun _ _ -> ()
-
-    method visit_abstraction_id_set : 'env -> abstraction_id_set -> unit =
-      fun env ids -> AbstractionId.Set.iter (self#visit_abstraction_id env) ids
-  end
-
-(** Ancestor for {!typed_avalue} map visitor *)
-class ['self] map_typed_avalue_base =
-  object (self : 'self)
-    inherit [_] map_aproj
-
-    method visit_region_var_id : 'env -> region_var_id -> region_var_id =
-      fun _ x -> x
-
-    method visit_region : 'env -> region -> region =
-      fun env r ->
-        match r with
-        | Static -> Static
-        | Var rid -> Var (self#visit_region_var_id env rid)
-
-    method visit_region_id : 'env -> region_id -> region_id = fun _ x -> x
-
-    method visit_region_id_set : 'env -> region_id_set -> region_id_set =
-      fun env ids -> RegionId.Set.map (self#visit_region_id env) ids
-
-    method visit_abstraction_id : 'env -> abstraction_id -> abstraction_id =
-      fun _ x -> x
-
-    method visit_abstraction_id_set
-        : 'env -> abstraction_id_set -> abstraction_id_set =
-      fun env ids -> AbstractionId.Set.map (self#visit_abstraction_id env) ids
-  end
 
 (** Abstraction values are used inside of abstractions to properly model
     borrowing relations introduced by function calls.
@@ -497,7 +347,7 @@ class ['self] map_typed_avalue_base =
     When calling a function, we lose information about the borrow graph:
     part of it is thus "abstracted" away.
 *)
-type avalue =
+and avalue =
   | AAdt of adt_avalue
   | ABottom (* TODO: remove once we change the way internal borrows are ended *)
   | ALoan of aloan_content
@@ -875,7 +725,10 @@ and aborrow_content =
     To be more precise, shared aloans have the borrow type (i.e., a shared aloan
     has type [& (mut) T] instead of [T]).
  *)
-and typed_avalue = { value : avalue; ty : rty }
+and typed_avalue = {
+  value : avalue;
+  ty : ty;  (** This should be a type with regions *)
+}
 [@@deriving
   show,
     ord,
diff --git a/compiler/ValuesUtils.ml b/compiler/ValuesUtils.ml
index 527434c1..2c7d213f 100644
--- a/compiler/ValuesUtils.ml
+++ b/compiler/ValuesUtils.ml
@@ -2,51 +2,64 @@ open Utils
 open TypesUtils
 open Types
 open Values
-module TA = TypesAnalysis
-include PrimitiveValuesUtils
+include Charon.ValuesUtils
 
 (** Utility exception *)
 exception FoundSymbolicValue of symbolic_value
 
 let mk_unit_value : typed_value =
-  { value = Adt { variant_id = None; field_values = [] }; ty = mk_unit_ty }
+  { value = VAdt { variant_id = None; field_values = [] }; ty = mk_unit_ty }
 
-let mk_typed_value (ty : ety) (value : value) : typed_value = { value; ty }
-let mk_typed_avalue (ty : rty) (value : avalue) : typed_avalue = { value; ty }
-let mk_bottom (ty : ety) : typed_value = { value = Bottom; ty }
-let mk_abottom (ty : rty) : typed_avalue = { value = ABottom; ty }
-let mk_aignored (ty : rty) : typed_avalue = { value = AIgnored; ty }
+let mk_typed_value (ty : ty) (value : value) : typed_value =
+  assert (ty_is_ety ty);
+  { value; ty }
+
+let mk_typed_avalue (ty : ty) (value : avalue) : typed_avalue =
+  assert (ty_is_rty ty);
+  { value; ty }
+
+let mk_bottom (ty : ty) : typed_value =
+  assert (ty_is_ety ty);
+  { value = VBottom; ty }
+
+let mk_abottom (ty : ty) : typed_avalue =
+  assert (ty_is_rty ty);
+  { value = ABottom; ty }
+
+let mk_aignored (ty : ty) : typed_avalue =
+  assert (ty_is_rty ty);
+  { value = AIgnored; ty }
 
 let value_as_symbolic (v : value) : symbolic_value =
-  match v with Symbolic v -> v | _ -> raise (Failure "Unexpected")
+  match v with VSymbolic v -> v | _ -> raise (Failure "Unexpected")
 
 (** Box a value *)
 let mk_box_value (v : typed_value) : typed_value =
   let box_ty = mk_box_ty v.ty in
-  let box_v = Adt { variant_id = None; field_values = [ v ] } in
+  let box_v = VAdt { variant_id = None; field_values = [ v ] } in
   mk_typed_value box_ty box_v
 
-let is_bottom (v : value) : bool = match v with Bottom -> true | _ -> false
+let is_bottom (v : value) : bool = match v with VBottom -> true | _ -> false
 
 let is_aignored (v : avalue) : bool =
   match v with AIgnored -> true | _ -> false
 
 let is_symbolic (v : value) : bool =
-  match v with Symbolic _ -> true | _ -> false
+  match v with VSymbolic _ -> true | _ -> false
 
 let as_symbolic (v : value) : symbolic_value =
-  match v with Symbolic s -> s | _ -> raise (Failure "Unexpected")
+  match v with VSymbolic s -> s | _ -> raise (Failure "Unexpected")
 
 let as_mut_borrow (v : typed_value) : BorrowId.id * typed_value =
   match v.value with
-  | Borrow (MutBorrow (bid, bv)) -> (bid, bv)
+  | VBorrow (VMutBorrow (bid, bv)) -> (bid, bv)
   | _ -> raise (Failure "Unexpected")
 
 let is_unit (v : typed_value) : bool =
   ty_is_unit v.ty
   &&
   match v.value with
-  | Adt av -> av.variant_id = None && av.field_values = []
+  | VAdt av -> av.variant_id = None && av.field_values = []
   | _ -> false
 
 (** Check if a value contains a *concrete* borrow (i.e., a [Borrow] value -
@@ -72,7 +85,7 @@ let reserved_in_value (v : typed_value) : bool =
   let obj =
     object
       inherit [_] iter_typed_value
-      method! visit_ReservedMutBorrow _env _ = raise Found
+      method! visit_VReservedMutBorrow _env _ = raise Found
     end
   in
   (* We use exceptions *)
@@ -130,14 +143,15 @@ let outer_loans_in_value (v : typed_value) : bool =
     false
   with Found -> true
 
-let find_first_primitively_copyable_sv_with_borrows (type_infos : TA.type_infos)
-    (v : typed_value) : symbolic_value option =
+let find_first_primitively_copyable_sv_with_borrows
+    (type_infos : TypesAnalysis.type_infos) (v : typed_value) :
+    symbolic_value option =
   (* The visitor *)
   let obj =
     object
       inherit [_] iter_typed_value
 
-      method! visit_Symbolic _ sv =
+      method! visit_VSymbolic _ sv =
         let ty = sv.sv_ty in
         if ty_is_primitively_copyable ty && ty_has_borrows type_infos ty then
           raise (FoundSymbolicValue sv)
@@ -157,12 +171,12 @@ let find_first_primitively_copyable_sv_with_borrows (type_infos : TA.type_infos)
  *)
 let rec value_strip_shared_loans (v : typed_value) : typed_value =
   match v.value with
-  | Loan (SharedLoan (_, v')) -> value_strip_shared_loans v'
+  | VLoan (VSharedLoan (_, v')) -> value_strip_shared_loans v'
   | _ -> v
 
 (** Check if a symbolic value has borrows *)
-let symbolic_value_has_borrows (infos : TA.type_infos) (sv : symbolic_value) :
-    bool =
+let symbolic_value_has_borrows (infos : TypesAnalysis.type_infos)
+    (sv : symbolic_value) : bool =
   ty_has_borrows infos sv.sv_ty
 
 (** Check if a value has borrows in **a general sense**.
@@ -171,7 +185,7 @@ let symbolic_value_has_borrows (infos : TA.type_infos) (sv : symbolic_value) :
     - there are concrete borrows
     - there are symbolic values which may contain borrows
  *)
-let value_has_borrows (infos : TA.type_infos) (v : value) : bool =
+let value_has_borrows (infos : TypesAnalysis.type_infos) (v : value) : bool =
   let obj =
     object
       inherit [_] iter_typed_value
@@ -212,7 +226,8 @@ let value_has_loans (v : value) : bool =
     - there are symbolic values which may contain borrows (symbolic values
       can't contain loans).
  *)
-let value_has_loans_or_borrows (infos : TA.type_infos) (v : value) : bool =
+let value_has_loans_or_borrows (infos : TypesAnalysis.type_infos) (v : value) :
+    bool =
   let obj =
     object
       inherit [_] iter_typed_value
@@ -237,7 +252,7 @@ let value_remove_shared_loans (v : typed_value) : typed_value =
 
       method! visit_typed_value env v =
         match v.value with
-        | Loan (SharedLoan (_, sv)) -> self#visit_typed_value env sv
+        | VLoan (VSharedLoan (_, sv)) -> self#visit_typed_value env sv
         | _ -> super#visit_typed_value env v
     end
   in
diff --git a/compiler/dune b/compiler/dune
index 648c7325..3a40e086 100644
--- a/compiler/dune
+++ b/compiler/dune
@@ -1,16 +1,16 @@
 (executable
- (name driver)
- (public_name aeneas_driver)
+ (name main)
+ (public_name aeneas)
  (package aeneas)
  (libraries aeneas)
- (modules Driver))
+ (modules Main))
 
 (library
  (name aeneas) ;; The name as used in the project
  (public_name aeneas) ;; The name as revealed to the projects importing this library
  (preprocess
   (pps ppx_deriving.show ppx_deriving.ord visitors.ppx))
- (libraries charon core_unix unionFind ocamlgraph)
+ (libraries charon core_unix unionFind ocamlgraph str)
  (modules
   AssociatedTypes
   Assumed
@@ -24,6 +24,7 @@
   Extract
   ExtractBase
   ExtractBuiltin
+  ExtractName
   ExtractTypes
   FunsAnalysis
   Identifiers
@@ -47,16 +48,14 @@
   LlbcOfJson
   Logging
   Meta
-  Names
   PrePasses
   Print
   PrintPure
-  PrimitiveValues
-  PrimitiveValuesUtils
   PureMicroPasses
   Pure
   PureTypeCheck
   PureUtils
+  RegionsHierarchy
   ReorderDecls
   SCC
   Scalars
@@ -85,7 +84,7 @@
    -g
    ;-dsource
    -warn-error
-   -5@8-9-11-14-33-20-21-26-27-39))
+   -5@8-11-14-33-20-21-26-27-39))
  (release
   (flags
    :standard
@@ -93,4 +92,4 @@
    -g
    ;-dsource
    -warn-error
-   -5@8-9-11-14-33-20-21-26-27-39)))
+   -5@8-11-14-33-20-21-26-27-39)))