WIP

4 files changed, 268 insertions, 271 deletions

diff --git a/backends/lean/Primitives.lean b/backends/lean/Primitives.lean
index 3ccb8466..e558e476 100644
--- a/backends/lean/Primitives.lean
+++ b/backends/lean/Primitives.lean
@@ -63,24 +63,28 @@ instance : Pure Result where
 -- rely on subtype, and a custom let-binding operator, in effect recreating our
 -- own variant of the do-dsl
 
-def Result.attach : (o : Result α) → Result { x : α // o = ret x }
+def Result.attach {α: Type} (o : Result α): Result { x : α // o = ret x } :=
+  match o with
   | .ret x => .ret ⟨x, rfl⟩
-  | .fail e   => .fail e
+  | .fail e => .fail e
 
-macro "let" h:ident " : " e:term " <-- " f:term : doElem =>
-  `(doElem| let ⟨$e, $h⟩ ← Result.attach $f)
+macro "let" e:term " ⟵ " f:term : doElem =>
+  `(doElem| let ⟨$e, h⟩ ← Result.attach $f)
 
--- Silly example of the kind of reasoning that this notation enables
+-- TODO: any way to factorize both definitions?
+macro "let" e:term " <-- " f:term : doElem =>
+  `(doElem| let ⟨$e, h⟩ ← Result.attach $f)
+
+-- We call the hypothesis `h`, in effect making it unavailable to the user
+-- (because too much shadowing). But in practice, once can use the French single
+-- quote notation (input with f< and f>), where `‹ h ›` finds a suitable
+-- hypothesis in the context, this is equivalent to `have x: h := by assumption in x`
 #eval do
-  let h: y <-- .ret (0: Nat)
-  let _: y = 0 := by cases h; decide
+  let y <-- .ret (0: Nat)
+  let _: y = 0 := by cases ‹ ret 0 = ret y › ; decide
   let r: { x: Nat // x = 0 } := ⟨ y, by assumption ⟩
   .ret r
 
--- TODO: ideally, `let <--` would automatically pick the name for the fresh
--- hypothesis, of the form `h_x` where `x` is the name of the variable, with
--- collision-avoidance. That way, code generation would be simpler.
-
 ----------------------
 -- MACHINE INTEGERS --
 ----------------------
@@ -151,13 +155,14 @@ def USize.checked_sub (n: USize) (m: USize): Result USize :=
   else
     fail integerOverflow
 
+@[simp]
+theorem usize_fits (n: Nat) (h: n <= 4294967295): n < USize.size :=
+  match USize.size, usize_size_eq with
+  | _, Or.inl rfl => Nat.lt_of_le_of_lt h (by decide)
+  | _, Or.inr rfl => Nat.lt_of_le_of_lt h (by decide)
+
 def USize.checked_add (n: USize) (m: USize): Result USize :=
-  if h: n.val.val + m.val.val <= 4294967295 then
-    .ret ⟨ n.val.val + m.val.val, by
-      have h': 4294967295 < USize.size := by intlit
-      apply Nat.lt_of_le_of_lt h h'
-    ⟩
-  else if h: n.val + m.val < USize.size then
+  if h: n.val + m.val < USize.size then
     .ret ⟨ n.val + m.val, h ⟩
   else
     .fail integerOverflow
@@ -173,12 +178,7 @@ def USize.checked_rem (n: USize) (m: USize): Result USize :=
     .fail integerOverflow
 
 def USize.checked_mul (n: USize) (m: USize): Result USize :=
-    if h: n.val.val * m.val.val <= 4294967295 then
-    .ret ⟨ n.val.val * m.val.val, by
-      have h': 4294967295 < USize.size := by intlit
-      apply Nat.lt_of_le_of_lt h h'
-    ⟩
-  else if h: n.val * m.val < USize.size then
+  if h: n.val * m.val < USize.size then
     .ret ⟨ n.val * m.val, h ⟩
   else
     .fail integerOverflow
@@ -193,7 +193,6 @@ def USize.checked_div (n: USize) (m: USize): Result USize :=
   else
     .fail integerOverflow
 
-
 -- Test behavior...
 #eval assert! USize.checked_sub 10 20 == fail integerOverflow; 0
 
@@ -358,6 +357,10 @@ def mem_replace_fwd (a : Type) (x : a) (_ : a) : a :=
 def mem_replace_back (a : Type) (_ : a) (y : a) : a :=
   y
 
+/-- Aeneas-translated function -- useful to reduce non-recursive definitions.
+ Use with `simp [ aeneas ]` -/
+register_simp_attr aeneas
+
 --------------------
 -- ASSERT COMMAND --
 --------------------
@@ -366,21 +369,24 @@ open Lean Elab Command Term Meta
 
 syntax (name := assert) "#assert" term: command
 
--- TODO: figure out how to make #assert behave as #eval followed by a compiler
--- error if the term doesn't reduce to True. Once we have that, add some inline
--- tests for the arithmetic operations, notably `rem`
-
 @[command_elab assert]
+unsafe
 def assertImpl : CommandElab := fun (_stx: Syntax) => do
-  logInfo "Reducing and asserting: "
-  logInfo _stx[1]
   runTermElabM (fun _ => do
-    let e ← Term.elabTerm _stx[1] none
-    logInfo (Expr.dbgToString e)
-    -- TODO: How to evaluate the term and compare the Result to true?
+    let r ← evalTerm Bool (mkConst ``Bool) _stx[1]
+    if not r then
+      logInfo "Assertion failed for: "
+      logInfo _stx[1]
+      logError "Expression reduced to false"
     pure ())
-  -- logInfo (Expr.dbgToString (``true))
-  -- throwError "TODO: assert"
 
 #eval 2 == 2
 #assert (2 == 2)
+
+-------------------
+-- SANITY CHECKS --
+-------------------
+
+-- TODO: add more once we have signed integers
+
+#assert (USize.checked_rem 1 2 == .ret 1)
diff --git a/compiler/Extract.ml b/compiler/Extract.ml
index a2ad37f5..c90d2170 100644
--- a/compiler/Extract.ml
+++ b/compiler/Extract.ml
@@ -1809,7 +1809,8 @@ and extract_lets (ctx : extraction_ctx) (fmt : F.formatter) (inside : bool)
           match !backend with
           | FStar -> "="
           | Coq -> ":="
-          | Lean -> if monadic then "<-" else ":="
+          (* TODO: switch to ⟵ once issues are fixed *)
+          | Lean -> if monadic then "←" else ":="
         in
         F.pp_print_string fmt eq;
         F.pp_print_space fmt ();
@@ -1867,6 +1868,8 @@ and extract_Switch (ctx : extraction_ctx) (fmt : F.formatter) (inside : bool)
       (* Open a box for the [if e] *)
       F.pp_open_hovbox fmt ctx.indent_incr;
       F.pp_print_string fmt "if";
+      if !backend = Lean then
+        F.pp_print_string fmt " h:";
       F.pp_print_space fmt ();
       let scrut_inside = PureUtils.texpression_requires_parentheses scrut in
       extract_texpression ctx fmt scrut_inside scrut;
@@ -1924,7 +1927,7 @@ and extract_Switch (ctx : extraction_ctx) (fmt : F.formatter) (inside : bool)
       F.pp_open_hovbox fmt ctx.indent_incr;
       (* Print the [match ... with] *)
       let match_begin =
-        match !backend with FStar -> "begin match" | Coq | Lean -> "match"
+        match !backend with FStar -> "begin match" | Coq -> "match" | Lean -> "match h:"
       in
       F.pp_print_string fmt match_begin;
       F.pp_print_space fmt ();
@@ -2647,7 +2650,7 @@ 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 ();
-        F.pp_print_string fmt "=";
+        F.pp_print_string fmt "==";
         F.pp_print_space fmt ();
         let success = ctx_get_variant (Assumed Result) result_return_id ctx in
         F.pp_print_string fmt ("." ^ success ^ " ())"));
diff --git a/tests/lean/hashmap_on_disk/Base/Primitives.lean b/tests/lean/hashmap_on_disk/Base/Primitives.lean
index b201d81a..e230dcab 100644
--- a/tests/lean/hashmap_on_disk/Base/Primitives.lean
+++ b/tests/lean/hashmap_on_disk/Base/Primitives.lean
@@ -63,24 +63,28 @@ instance : Pure Result where
 -- rely on subtype, and a custom let-binding operator, in effect recreating our
 -- own variant of the do-dsl
 
-def Result.attach : (o : Result α) → Result { x : α // o = ret x }
+def Result.attach {α: Type} (o : Result α): Result { x : α // o = ret x } :=
+  match o with
   | .ret x => .ret ⟨x, rfl⟩
-  | .fail e   => .fail e
+  | .fail e => .fail e
 
-macro "let" h:ident " : " e:term " <-- " f:term : doElem =>
-  `(doElem| let ⟨$e, $h⟩ ← Result.attach $f)
+macro "let" e:term " ⟵ " f:term : doElem =>
+  `(doElem| let ⟨$e, h⟩ ← Result.attach $f)
 
--- Silly example of the kind of reasoning that this notation enables
+-- TODO: any way to factorize both definitions?
+macro "let" e:term " <-- " f:term : doElem =>
+  `(doElem| let ⟨$e, h⟩ ← Result.attach $f)
+
+-- We call the hypothesis `h`, in effect making it unavailable to the user
+-- (because too much shadowing). But in practice, once can use the French single
+-- quote notation (input with f< and f>), where `‹ h ›` finds a suitable
+-- hypothesis in the context, this is equivalent to `have x: h := by assumption in x`
 #eval do
-  let h: y <-- .ret (0: Nat)
-  let _: y = 0 := by cases h; decide
+  let y <-- .ret (0: Nat)
+  let _: y = 0 := by cases ‹ ret 0 = ret y › ; decide
   let r: { x: Nat // x = 0 } := ⟨ y, by assumption ⟩
   .ret r
 
--- TODO: ideally, `let <--` would automatically pick the name for the fresh
--- hypothesis, of the form `h_x` where `x` is the name of the variable, with
--- collision-avoidance. That way, code generation would be simpler.
-
 ----------------------
 -- MACHINE INTEGERS --
 ----------------------
@@ -151,13 +155,14 @@ def USize.checked_sub (n: USize) (m: USize): Result USize :=
   else
     fail integerOverflow
 
+@[simp]
+theorem usize_fits (n: Nat) (h: n <= 4294967295): n < USize.size :=
+  match USize.size, usize_size_eq with
+  | _, Or.inl rfl => Nat.lt_of_le_of_lt h (by decide)
+  | _, Or.inr rfl => Nat.lt_of_le_of_lt h (by decide)
+
 def USize.checked_add (n: USize) (m: USize): Result USize :=
-  if h: n.val.val + m.val.val <= 4294967295 then
-    .ret ⟨ n.val.val + m.val.val, by
-      have h': 4294967295 < USize.size := by intlit
-      apply Nat.lt_of_le_of_lt h h'
-    ⟩
-  else if h: n.val + m.val < USize.size then
+  if h: n.val + m.val < USize.size then
     .ret ⟨ n.val + m.val, h ⟩
   else
     .fail integerOverflow
@@ -173,12 +178,7 @@ def USize.checked_rem (n: USize) (m: USize): Result USize :=
     .fail integerOverflow
 
 def USize.checked_mul (n: USize) (m: USize): Result USize :=
-    if h: n.val.val * m.val.val <= 4294967295 then
-    .ret ⟨ n.val.val * m.val.val, by
-      have h': 4294967295 < USize.size := by intlit
-      apply Nat.lt_of_le_of_lt h h'
-    ⟩
-  else if h: n.val * m.val < USize.size then
+  if h: n.val * m.val < USize.size then
     .ret ⟨ n.val * m.val, h ⟩
   else
     .fail integerOverflow
@@ -193,7 +193,6 @@ def USize.checked_div (n: USize) (m: USize): Result USize :=
   else
     .fail integerOverflow
 
-
 -- Test behavior...
 #eval assert! USize.checked_sub 10 20 == fail integerOverflow; 0
 
@@ -358,6 +357,10 @@ def mem_replace_fwd (a : Type) (x : a) (_ : a) : a :=
 def mem_replace_back (a : Type) (_ : a) (y : a) : a :=
   y
 
+/-- Aeneas-translated function -- useful to reduce non-recursive definitions.
+ Use with `simp [ aeneas ]` -/
+register_simp_attr aeneas
+
 --------------------
 -- ASSERT COMMAND --
 --------------------
@@ -366,21 +369,24 @@ open Lean Elab Command Term Meta
 
 syntax (name := assert) "#assert" term: command
 
--- TODO: figure out how to make #assert behave as #eval followed by a compiler
--- error if the term doesn't reduce to True. Once we have that, add some inline
--- tests for the arithmetic operations, notably `rem`
-
 @[command_elab assert]
+unsafe
 def assertImpl : CommandElab := fun (_stx: Syntax) => do
-  logInfo "Reducing and asserting: "
-  logInfo _stx[1]
   runTermElabM (fun _ => do
-    let e ← Term.elabTerm _stx[1] none
-    logInfo (Expr.dbgToString e)
-    -- TODO: How to evaluate the term and compare the Result to true?
+    let r ← evalTerm Bool (mkConst ``Bool) _stx[1]
+    if not r then
+      logInfo "Assertion failed for: "
+      logInfo _stx[1]
+      logError "Expression reduced to false"
     pure ())
-  -- logInfo (Expr.dbgToString (``true))
-  -- throwError "TODO: assert"
 
 #eval 2 == 2
 #assert (2 == 2)
+
+-------------------
+-- SANITY CHECKS --
+-------------------
+
+-- TODO: add more once we have signed integers
+
+#assert (USize.checked_rem 1 2 == .ret 1)
diff --git a/tests/lean/hashmap_on_disk/HashmapMain/Funs.lean b/tests/lean/hashmap_on_disk/HashmapMain/Funs.lean
index ee50f126..392c8816 100644
--- a/tests/lean/hashmap_on_disk/HashmapMain/Funs.lean
+++ b/tests/lean/hashmap_on_disk/HashmapMain/Funs.lean
@@ -3,29 +3,29 @@
 import Base.Primitives
 import HashmapMain.Types
 import HashmapMain.Opaque
-import HashmapMain.Clauses.Template
+import HashmapMain.Clauses.Clauses
 
 section variable (opaque_defs: OpaqueDefs)
 
 /- [hashmap_main::hashmap::hash_key] -/
-def hashmap_hash_key_fwd (k : USize) : Result USize := Result.ret k
+def hashmap_hash_key_fwd (k : USize) : Result USize :=
+  Result.ret k
 
 /- [hashmap_main::hashmap::HashMap::{0}::allocate_slots] -/
 def hashmap_hash_map_allocate_slots_loop_fwd
   (T : Type) (slots : Vec (hashmap_list_t T)) (n : USize) :
   (Result (Vec (hashmap_list_t T)))
   :=
-  if n > (USize.ofNatCore 0 (by intlit))
+  if h: n > (USize.ofNatCore 0 (by intlit))
   then
     do
-      let slots0 <-
-        vec_push_back (hashmap_list_t T) slots hashmap_list_t.HashmapListNil 
-      let n0 <- USize.checked_sub n (USize.ofNatCore 1 (by intlit)) 
+      let slots0 ←
+        vec_push_back (hashmap_list_t T) slots hashmap_list_t.HashmapListNil
+      let n0 ← USize.checked_sub n (USize.ofNatCore 1 (by intlit))
       hashmap_hash_map_allocate_slots_loop_fwd T slots0 n0
   else Result.ret slots
 termination_by hashmap_hash_map_allocate_slots_loop_fwd slots n =>
-                                                                  hashmap_hash_map_allocate_slots_loop_terminates
-                                                                  T slots n 
+  hashmap_hash_map_allocate_slots_loop_terminates T slots n
 decreasing_by hashmap_hash_map_allocate_slots_loop_decreases slots n
 
 /- [hashmap_main::hashmap::HashMap::{0}::allocate_slots] -/
@@ -42,10 +42,10 @@ def hashmap_hash_map_new_with_capacity_fwd
   Result (hashmap_hash_map_t T)
   :=
   do
-    let v := vec_new (hashmap_list_t T) 
-    let slots <- hashmap_hash_map_allocate_slots_fwd T v capacity 
-    let i <- USize.checked_mul capacity max_load_dividend 
-    let i0 <- USize.checked_div i max_load_divisor 
+    let v := vec_new (hashmap_list_t T)
+    let slots ← hashmap_hash_map_allocate_slots_fwd T v capacity
+    let i ← USize.checked_mul capacity max_load_dividend
+    let i0 ← USize.checked_div i max_load_divisor
     Result.ret
       {
         hashmap_hash_map_num_entries := (USize.ofNatCore 0 (by intlit)),
@@ -65,19 +65,18 @@ def hashmap_hash_map_clear_slots_loop_fwd_back
   (T : Type) (slots : Vec (hashmap_list_t T)) (i : USize) :
   (Result (Vec (hashmap_list_t T)))
   :=
-  let i0 := vec_len (hashmap_list_t T) slots 
-  if i < i0
+  let i0 := vec_len (hashmap_list_t T) slots
+  if h: i < i0
   then
     do
-      let i1 <- USize.checked_add i (USize.ofNatCore 1 (by intlit)) 
-      let slots0 <-
+      let i1 ← USize.checked_add i (USize.ofNatCore 1 (by intlit))
+      let slots0 ←
         vec_index_mut_back (hashmap_list_t T) slots i
-          hashmap_list_t.HashmapListNil 
+          hashmap_list_t.HashmapListNil
       hashmap_hash_map_clear_slots_loop_fwd_back T slots0 i1
   else Result.ret slots
 termination_by hashmap_hash_map_clear_slots_loop_fwd_back slots i =>
-                                                                    hashmap_hash_map_clear_slots_loop_terminates
-                                                                    T slots i 
+  hashmap_hash_map_clear_slots_loop_terminates T slots i
 decreasing_by hashmap_hash_map_clear_slots_loop_decreases slots i
 
 /- [hashmap_main::hashmap::HashMap::{0}::clear_slots] -/
@@ -92,8 +91,8 @@ def hashmap_hash_map_clear_slots_fwd_back
 def hashmap_hash_map_clear_fwd_back
   (T : Type) (self : hashmap_hash_map_t T) : Result (hashmap_hash_map_t T) :=
   do
-    let v <-
-      hashmap_hash_map_clear_slots_fwd_back T self.hashmap_hash_map_slots 
+    let v ←
+      hashmap_hash_map_clear_slots_fwd_back T self.hashmap_hash_map_slots
     Result.ret
       {
         hashmap_hash_map_num_entries := (USize.ofNatCore 0 (by intlit)),
@@ -112,15 +111,14 @@ def hashmap_hash_map_insert_in_list_loop_fwd
   (T : Type) (key : USize) (value : T) (ls : hashmap_list_t T) :
   (Result Bool)
   :=
-  match ls with
+  match h: ls with
   | hashmap_list_t.HashmapListCons ckey cvalue tl =>
-    if ckey = key
+    if h: ckey = key
     then Result.ret false
     else hashmap_hash_map_insert_in_list_loop_fwd T key value tl
   | hashmap_list_t.HashmapListNil => Result.ret true
-  
 termination_by hashmap_hash_map_insert_in_list_loop_fwd key value ls =>
-   hashmap_hash_map_insert_in_list_loop_terminates T key value ls 
+  hashmap_hash_map_insert_in_list_loop_terminates T key value ls
 decreasing_by hashmap_hash_map_insert_in_list_loop_decreases key value ls
 
 /- [hashmap_main::hashmap::HashMap::{0}::insert_in_list] -/
@@ -133,20 +131,19 @@ def hashmap_hash_map_insert_in_list_loop_back
   (T : Type) (key : USize) (value : T) (ls : hashmap_list_t T) :
   (Result (hashmap_list_t T))
   :=
-  match ls with
+  match h: ls with
   | hashmap_list_t.HashmapListCons ckey cvalue tl =>
-    if ckey = key
+    if h: ckey = key
     then Result.ret (hashmap_list_t.HashmapListCons ckey value tl)
     else
       do
-        let tl0 <- hashmap_hash_map_insert_in_list_loop_back T key value tl 
+        let tl0 ← hashmap_hash_map_insert_in_list_loop_back T key value tl
         Result.ret (hashmap_list_t.HashmapListCons ckey cvalue tl0)
   | hashmap_list_t.HashmapListNil =>
-    let l := hashmap_list_t.HashmapListNil 
+    let l := hashmap_list_t.HashmapListNil
     Result.ret (hashmap_list_t.HashmapListCons key value l)
-  
 termination_by hashmap_hash_map_insert_in_list_loop_back key value ls =>
-   hashmap_hash_map_insert_in_list_loop_terminates T key value ls 
+  hashmap_hash_map_insert_in_list_loop_terminates T key value ls
 decreasing_by hashmap_hash_map_insert_in_list_loop_decreases key value ls
 
 /- [hashmap_main::hashmap::HashMap::{0}::insert_in_list] -/
@@ -162,21 +159,21 @@ def hashmap_hash_map_insert_no_resize_fwd_back
   Result (hashmap_hash_map_t T)
   :=
   do
-    let hash <- hashmap_hash_key_fwd key 
-    let i := vec_len (hashmap_list_t T) self.hashmap_hash_map_slots 
-    let hash_mod <- USize.checked_rem hash i 
-    let l <-
-      vec_index_mut_fwd (hashmap_list_t T) self.hashmap_hash_map_slots hash_mod 
-    let inserted <- hashmap_hash_map_insert_in_list_fwd T key value l 
-    if inserted
+    let hash ← hashmap_hash_key_fwd key
+    let i := vec_len (hashmap_list_t T) self.hashmap_hash_map_slots
+    let hash_mod ← USize.checked_rem hash i
+    let l ←
+      vec_index_mut_fwd (hashmap_list_t T) self.hashmap_hash_map_slots hash_mod
+    let inserted ← hashmap_hash_map_insert_in_list_fwd T key value l
+    if h: inserted
     then
       do
-        let i0 <- USize.checked_add self.hashmap_hash_map_num_entries
-          (USize.ofNatCore 1 (by intlit)) 
-        let l0 <- hashmap_hash_map_insert_in_list_back T key value l 
-        let v <-
+        let i0 ← USize.checked_add self.hashmap_hash_map_num_entries
+          (USize.ofNatCore 1 (by intlit))
+        let l0 ← hashmap_hash_map_insert_in_list_back T key value l
+        let v ←
           vec_index_mut_back (hashmap_list_t T) self.hashmap_hash_map_slots
-            hash_mod l0 
+            hash_mod l0
         Result.ret
           {
             hashmap_hash_map_num_entries := i0,
@@ -186,10 +183,10 @@ def hashmap_hash_map_insert_no_resize_fwd_back
           }
     else
       do
-        let l0 <- hashmap_hash_map_insert_in_list_back T key value l 
-        let v <-
+        let l0 ← hashmap_hash_map_insert_in_list_back T key value l
+        let v ←
           vec_index_mut_back (hashmap_list_t T) self.hashmap_hash_map_slots
-            hash_mod l0 
+            hash_mod l0
         Result.ret
           {
             hashmap_hash_map_num_entries := self.hashmap_hash_map_num_entries,
@@ -208,16 +205,15 @@ def hashmap_hash_map_move_elements_from_list_loop_fwd_back
   (T : Type) (ntable : hashmap_hash_map_t T) (ls : hashmap_list_t T) :
   (Result (hashmap_hash_map_t T))
   :=
-  match ls with
+  match h: ls with
   | hashmap_list_t.HashmapListCons k v tl =>
     do
-      let ntable0 <- hashmap_hash_map_insert_no_resize_fwd_back T ntable k v 
+      let ntable0 ← hashmap_hash_map_insert_no_resize_fwd_back T ntable k v
       hashmap_hash_map_move_elements_from_list_loop_fwd_back T ntable0 tl
   | hashmap_list_t.HashmapListNil => Result.ret ntable
-  
 termination_by hashmap_hash_map_move_elements_from_list_loop_fwd_back ntable ls
-              => hashmap_hash_map_move_elements_from_list_loop_terminates T
-                ntable ls 
+  =>
+  hashmap_hash_map_move_elements_from_list_loop_terminates T ntable ls
 decreasing_by hashmap_hash_map_move_elements_from_list_loop_decreases ntable ls
 
 /- [hashmap_main::hashmap::HashMap::{0}::move_elements_from_list] -/
@@ -233,23 +229,23 @@ def hashmap_hash_map_move_elements_loop_fwd_back
   (i : USize) :
   (Result ((hashmap_hash_map_t T) × (Vec (hashmap_list_t T))))
   :=
-  let i0 := vec_len (hashmap_list_t T) slots 
-  if i < i0
+  let i0 := vec_len (hashmap_list_t T) slots
+  if h: i < i0
   then
     do
-      let l <- vec_index_mut_fwd (hashmap_list_t T) slots i 
+      let l ← vec_index_mut_fwd (hashmap_list_t T) slots i
       let ls :=
-        mem_replace_fwd (hashmap_list_t T) l hashmap_list_t.HashmapListNil 
-      let ntable0 <-
-        hashmap_hash_map_move_elements_from_list_fwd_back T ntable ls 
-      let i1 <- USize.checked_add i (USize.ofNatCore 1 (by intlit)) 
+        mem_replace_fwd (hashmap_list_t T) l hashmap_list_t.HashmapListNil
+      let ntable0 ←
+        hashmap_hash_map_move_elements_from_list_fwd_back T ntable ls
+      let i1 ← USize.checked_add i (USize.ofNatCore 1 (by intlit))
       let l0 :=
-        mem_replace_back (hashmap_list_t T) l hashmap_list_t.HashmapListNil 
-      let slots0 <- vec_index_mut_back (hashmap_list_t T) slots i l0 
+        mem_replace_back (hashmap_list_t T) l hashmap_list_t.HashmapListNil
+      let slots0 ← vec_index_mut_back (hashmap_list_t T) slots i l0
       hashmap_hash_map_move_elements_loop_fwd_back T ntable0 slots0 i1
   else Result.ret (ntable, slots)
 termination_by hashmap_hash_map_move_elements_loop_fwd_back ntable slots i =>
-   hashmap_hash_map_move_elements_loop_terminates T ntable slots i 
+  hashmap_hash_map_move_elements_loop_terminates T ntable slots i
 decreasing_by hashmap_hash_map_move_elements_loop_decreases ntable slots i
 
 /- [hashmap_main::hashmap::HashMap::{0}::move_elements] -/
@@ -264,19 +260,19 @@ def hashmap_hash_map_move_elements_fwd_back
 def hashmap_hash_map_try_resize_fwd_back
   (T : Type) (self : hashmap_hash_map_t T) : Result (hashmap_hash_map_t T) :=
   do
-    let max_usize <- scalar_cast USize core_num_u32_max_c 
-    let capacity := vec_len (hashmap_list_t T) self.hashmap_hash_map_slots 
-    let n1 <- USize.checked_div max_usize (USize.ofNatCore 2 (by intlit)) 
-    let (i, i0) := self.hashmap_hash_map_max_load_factor 
-    let i1 <- USize.checked_div n1 i 
-    if capacity <= i1
+    let max_usize ← scalar_cast USize core_num_u32_max_c
+    let capacity := vec_len (hashmap_list_t T) self.hashmap_hash_map_slots
+    let n1 ← USize.checked_div max_usize (USize.ofNatCore 2 (by intlit))
+    let (i, i0) := self.hashmap_hash_map_max_load_factor
+    let i1 ← USize.checked_div n1 i
+    if h: capacity <= i1
     then
       do
-        let i2 <- USize.checked_mul capacity (USize.ofNatCore 2 (by intlit)) 
-        let ntable <- hashmap_hash_map_new_with_capacity_fwd T i2 i i0 
-        let (ntable0, _) <-
+        let i2 ← USize.checked_mul capacity (USize.ofNatCore 2 (by intlit))
+        let ntable ← hashmap_hash_map_new_with_capacity_fwd T i2 i i0
+        let (ntable0, _) ←
           hashmap_hash_map_move_elements_fwd_back T ntable
-            self.hashmap_hash_map_slots (USize.ofNatCore 0 (by intlit)) 
+            self.hashmap_hash_map_slots (USize.ofNatCore 0 (by intlit))
         Result.ret
           {
             hashmap_hash_map_num_entries := self.hashmap_hash_map_num_entries,
@@ -299,24 +295,23 @@ def hashmap_hash_map_insert_fwd_back
   Result (hashmap_hash_map_t T)
   :=
   do
-    let self0 <- hashmap_hash_map_insert_no_resize_fwd_back T self key value 
-    let i <- hashmap_hash_map_len_fwd T self0 
-    if i > self0.hashmap_hash_map_max_load
+    let self0 ← hashmap_hash_map_insert_no_resize_fwd_back T self key value
+    let i ← hashmap_hash_map_len_fwd T self0
+    if h: i > self0.hashmap_hash_map_max_load
     then hashmap_hash_map_try_resize_fwd_back T self0
     else Result.ret self0
 
 /- [hashmap_main::hashmap::HashMap::{0}::contains_key_in_list] -/
 def hashmap_hash_map_contains_key_in_list_loop_fwd
   (T : Type) (key : USize) (ls : hashmap_list_t T) : (Result Bool) :=
-  match ls with
+  match h: ls with
   | hashmap_list_t.HashmapListCons ckey t tl =>
-    if ckey = key
+    if h: ckey = key
     then Result.ret true
     else hashmap_hash_map_contains_key_in_list_loop_fwd T key tl
   | hashmap_list_t.HashmapListNil => Result.ret false
-  
 termination_by hashmap_hash_map_contains_key_in_list_loop_fwd key ls =>
-   hashmap_hash_map_contains_key_in_list_loop_terminates T key ls 
+  hashmap_hash_map_contains_key_in_list_loop_terminates T key ls
 decreasing_by hashmap_hash_map_contains_key_in_list_loop_decreases key ls
 
 /- [hashmap_main::hashmap::HashMap::{0}::contains_key_in_list] -/
@@ -328,26 +323,24 @@ def hashmap_hash_map_contains_key_in_list_fwd
 def hashmap_hash_map_contains_key_fwd
   (T : Type) (self : hashmap_hash_map_t T) (key : USize) : Result Bool :=
   do
-    let hash <- hashmap_hash_key_fwd key 
-    let i := vec_len (hashmap_list_t T) self.hashmap_hash_map_slots 
-    let hash_mod <- USize.checked_rem hash i 
-    let l <-
-      vec_index_fwd (hashmap_list_t T) self.hashmap_hash_map_slots hash_mod 
+    let hash ← hashmap_hash_key_fwd key
+    let i := vec_len (hashmap_list_t T) self.hashmap_hash_map_slots
+    let hash_mod ← USize.checked_rem hash i
+    let l ←
+      vec_index_fwd (hashmap_list_t T) self.hashmap_hash_map_slots hash_mod
     hashmap_hash_map_contains_key_in_list_fwd T key l
 
 /- [hashmap_main::hashmap::HashMap::{0}::get_in_list] -/
 def hashmap_hash_map_get_in_list_loop_fwd
   (T : Type) (key : USize) (ls : hashmap_list_t T) : (Result T) :=
-  match ls with
+  match h: ls with
   | hashmap_list_t.HashmapListCons ckey cvalue tl =>
-    if ckey = key
+    if h: ckey = key
     then Result.ret cvalue
     else hashmap_hash_map_get_in_list_loop_fwd T key tl
   | hashmap_list_t.HashmapListNil => Result.fail Error.panic
-  
 termination_by hashmap_hash_map_get_in_list_loop_fwd key ls =>
-                                                              hashmap_hash_map_get_in_list_loop_terminates
-                                                              T key ls 
+  hashmap_hash_map_get_in_list_loop_terminates T key ls
 decreasing_by hashmap_hash_map_get_in_list_loop_decreases key ls
 
 /- [hashmap_main::hashmap::HashMap::{0}::get_in_list] -/
@@ -359,26 +352,24 @@ def hashmap_hash_map_get_in_list_fwd
 def hashmap_hash_map_get_fwd
   (T : Type) (self : hashmap_hash_map_t T) (key : USize) : Result T :=
   do
-    let hash <- hashmap_hash_key_fwd key 
-    let i := vec_len (hashmap_list_t T) self.hashmap_hash_map_slots 
-    let hash_mod <- USize.checked_rem hash i 
-    let l <-
-      vec_index_fwd (hashmap_list_t T) self.hashmap_hash_map_slots hash_mod 
+    let hash ← hashmap_hash_key_fwd key
+    let i := vec_len (hashmap_list_t T) self.hashmap_hash_map_slots
+    let hash_mod ← USize.checked_rem hash i
+    let l ←
+      vec_index_fwd (hashmap_list_t T) self.hashmap_hash_map_slots hash_mod
     hashmap_hash_map_get_in_list_fwd T key l
 
 /- [hashmap_main::hashmap::HashMap::{0}::get_mut_in_list] -/
 def hashmap_hash_map_get_mut_in_list_loop_fwd
   (T : Type) (ls : hashmap_list_t T) (key : USize) : (Result T) :=
-  match ls with
+  match h: ls with
   | hashmap_list_t.HashmapListCons ckey cvalue tl =>
-    if ckey = key
+    if h: ckey = key
     then Result.ret cvalue
     else hashmap_hash_map_get_mut_in_list_loop_fwd T tl key
   | hashmap_list_t.HashmapListNil => Result.fail Error.panic
-  
 termination_by hashmap_hash_map_get_mut_in_list_loop_fwd ls key =>
-                                                                  hashmap_hash_map_get_mut_in_list_loop_terminates
-                                                                  T ls key 
+  hashmap_hash_map_get_mut_in_list_loop_terminates T ls key
 decreasing_by hashmap_hash_map_get_mut_in_list_loop_decreases ls key
 
 /- [hashmap_main::hashmap::HashMap::{0}::get_mut_in_list] -/
@@ -391,18 +382,17 @@ def hashmap_hash_map_get_mut_in_list_loop_back
   (T : Type) (ls : hashmap_list_t T) (key : USize) (ret0 : T) :
   (Result (hashmap_list_t T))
   :=
-  match ls with
+  match h: ls with
   | hashmap_list_t.HashmapListCons ckey cvalue tl =>
-    if ckey = key
+    if h: ckey = key
     then Result.ret (hashmap_list_t.HashmapListCons ckey ret0 tl)
     else
       do
-        let tl0 <- hashmap_hash_map_get_mut_in_list_loop_back T tl key ret0 
+        let tl0 ← hashmap_hash_map_get_mut_in_list_loop_back T tl key ret0
         Result.ret (hashmap_list_t.HashmapListCons ckey cvalue tl0)
   | hashmap_list_t.HashmapListNil => Result.fail Error.panic
-  
 termination_by hashmap_hash_map_get_mut_in_list_loop_back ls key ret0 =>
-   hashmap_hash_map_get_mut_in_list_loop_terminates T ls key 
+  hashmap_hash_map_get_mut_in_list_loop_terminates T ls key
 decreasing_by hashmap_hash_map_get_mut_in_list_loop_decreases ls key
 
 /- [hashmap_main::hashmap::HashMap::{0}::get_mut_in_list] -/
@@ -416,11 +406,11 @@ def hashmap_hash_map_get_mut_in_list_back
 def hashmap_hash_map_get_mut_fwd
   (T : Type) (self : hashmap_hash_map_t T) (key : USize) : Result T :=
   do
-    let hash <- hashmap_hash_key_fwd key 
-    let i := vec_len (hashmap_list_t T) self.hashmap_hash_map_slots 
-    let hash_mod <- USize.checked_rem hash i 
-    let l <-
-      vec_index_mut_fwd (hashmap_list_t T) self.hashmap_hash_map_slots hash_mod 
+    let hash ← hashmap_hash_key_fwd key
+    let i := vec_len (hashmap_list_t T) self.hashmap_hash_map_slots
+    let hash_mod ← USize.checked_rem hash i
+    let l ←
+      vec_index_mut_fwd (hashmap_list_t T) self.hashmap_hash_map_slots hash_mod
     hashmap_hash_map_get_mut_in_list_fwd T l key
 
 /- [hashmap_main::hashmap::HashMap::{0}::get_mut] -/
@@ -429,15 +419,15 @@ def hashmap_hash_map_get_mut_back
   Result (hashmap_hash_map_t T)
   :=
   do
-    let hash <- hashmap_hash_key_fwd key 
-    let i := vec_len (hashmap_list_t T) self.hashmap_hash_map_slots 
-    let hash_mod <- USize.checked_rem hash i 
-    let l <-
-      vec_index_mut_fwd (hashmap_list_t T) self.hashmap_hash_map_slots hash_mod 
-    let l0 <- hashmap_hash_map_get_mut_in_list_back T l key ret0 
-    let v <-
+    let hash ← hashmap_hash_key_fwd key
+    let i := vec_len (hashmap_list_t T) self.hashmap_hash_map_slots
+    let hash_mod ← USize.checked_rem hash i
+    let l ←
+      vec_index_mut_fwd (hashmap_list_t T) self.hashmap_hash_map_slots hash_mod
+    let l0 ← hashmap_hash_map_get_mut_in_list_back T l key ret0
+    let v ←
       vec_index_mut_back (hashmap_list_t T) self.hashmap_hash_map_slots
-        hash_mod l0 
+        hash_mod l0
     Result.ret
       {
         hashmap_hash_map_num_entries := self.hashmap_hash_map_num_entries,
@@ -449,24 +439,21 @@ def hashmap_hash_map_get_mut_back
 /- [hashmap_main::hashmap::HashMap::{0}::remove_from_list] -/
 def hashmap_hash_map_remove_from_list_loop_fwd
   (T : Type) (key : USize) (ls : hashmap_list_t T) : (Result (Option T)) :=
-  match ls with
+  match h: ls with
   | hashmap_list_t.HashmapListCons ckey t tl =>
-    if ckey = key
+    if h: ckey = key
     then
       let mv_ls :=
         mem_replace_fwd (hashmap_list_t T) (hashmap_list_t.HashmapListCons ckey
-          t tl) hashmap_list_t.HashmapListNil 
-      match mv_ls with
+          t tl) hashmap_list_t.HashmapListNil
+      match h: mv_ls with
       | hashmap_list_t.HashmapListCons i cvalue tl0 =>
         Result.ret (Option.some cvalue)
       | hashmap_list_t.HashmapListNil => Result.fail Error.panic
-      
     else hashmap_hash_map_remove_from_list_loop_fwd T key tl
   | hashmap_list_t.HashmapListNil => Result.ret Option.none
-  
 termination_by hashmap_hash_map_remove_from_list_loop_fwd key ls =>
-                                                                   hashmap_hash_map_remove_from_list_loop_terminates
-                                                                   T key ls 
+  hashmap_hash_map_remove_from_list_loop_terminates T key ls
 decreasing_by hashmap_hash_map_remove_from_list_loop_decreases key ls
 
 /- [hashmap_main::hashmap::HashMap::{0}::remove_from_list] -/
@@ -479,26 +466,23 @@ def hashmap_hash_map_remove_from_list_loop_back
   (T : Type) (key : USize) (ls : hashmap_list_t T) :
   (Result (hashmap_list_t T))
   :=
-  match ls with
+  match h: ls with
   | hashmap_list_t.HashmapListCons ckey t tl =>
-    if ckey = key
+    if h: ckey = key
     then
       let mv_ls :=
         mem_replace_fwd (hashmap_list_t T) (hashmap_list_t.HashmapListCons ckey
-          t tl) hashmap_list_t.HashmapListNil 
-      match mv_ls with
+          t tl) hashmap_list_t.HashmapListNil
+      match h: mv_ls with
       | hashmap_list_t.HashmapListCons i cvalue tl0 => Result.ret tl0
       | hashmap_list_t.HashmapListNil => Result.fail Error.panic
-      
     else
       do
-        let tl0 <- hashmap_hash_map_remove_from_list_loop_back T key tl 
+        let tl0 ← hashmap_hash_map_remove_from_list_loop_back T key tl
         Result.ret (hashmap_list_t.HashmapListCons ckey t tl0)
   | hashmap_list_t.HashmapListNil => Result.ret hashmap_list_t.HashmapListNil
-  
 termination_by hashmap_hash_map_remove_from_list_loop_back key ls =>
-                                                                    hashmap_hash_map_remove_from_list_loop_terminates
-                                                                    T key ls 
+  hashmap_hash_map_remove_from_list_loop_terminates T key ls
 decreasing_by hashmap_hash_map_remove_from_list_loop_decreases key ls
 
 /- [hashmap_main::hashmap::HashMap::{0}::remove_from_list] -/
@@ -512,20 +496,19 @@ def hashmap_hash_map_remove_from_list_back
 def hashmap_hash_map_remove_fwd
   (T : Type) (self : hashmap_hash_map_t T) (key : USize) : Result (Option T) :=
   do
-    let hash <- hashmap_hash_key_fwd key 
-    let i := vec_len (hashmap_list_t T) self.hashmap_hash_map_slots 
-    let hash_mod <- USize.checked_rem hash i 
-    let l <-
-      vec_index_mut_fwd (hashmap_list_t T) self.hashmap_hash_map_slots hash_mod 
-    let x <- hashmap_hash_map_remove_from_list_fwd T key l 
-    match x with
+    let hash ← hashmap_hash_key_fwd key
+    let i := vec_len (hashmap_list_t T) self.hashmap_hash_map_slots
+    let hash_mod ← USize.checked_rem hash i
+    let l ←
+      vec_index_mut_fwd (hashmap_list_t T) self.hashmap_hash_map_slots hash_mod
+    let x ← hashmap_hash_map_remove_from_list_fwd T key l
+    match h: x with
     | Option.none => Result.ret Option.none
     | Option.some x0 =>
       do
-        let _ <- USize.checked_sub self.hashmap_hash_map_num_entries
-          (USize.ofNatCore 1 (by intlit)) 
+        let _ ← USize.checked_sub self.hashmap_hash_map_num_entries
+          (USize.ofNatCore 1 (by intlit))
         Result.ret (Option.some x0)
-    
 
 /- [hashmap_main::hashmap::HashMap::{0}::remove] -/
 def hashmap_hash_map_remove_back
@@ -533,19 +516,19 @@ def hashmap_hash_map_remove_back
   Result (hashmap_hash_map_t T)
   :=
   do
-    let hash <- hashmap_hash_key_fwd key 
-    let i := vec_len (hashmap_list_t T) self.hashmap_hash_map_slots 
-    let hash_mod <- USize.checked_rem hash i 
-    let l <-
-      vec_index_mut_fwd (hashmap_list_t T) self.hashmap_hash_map_slots hash_mod 
-    let x <- hashmap_hash_map_remove_from_list_fwd T key l 
-    match x with
+    let hash ← hashmap_hash_key_fwd key
+    let i := vec_len (hashmap_list_t T) self.hashmap_hash_map_slots
+    let hash_mod ← USize.checked_rem hash i
+    let l ←
+      vec_index_mut_fwd (hashmap_list_t T) self.hashmap_hash_map_slots hash_mod
+    let x ← hashmap_hash_map_remove_from_list_fwd T key l
+    match h: x with
     | Option.none =>
       do
-        let l0 <- hashmap_hash_map_remove_from_list_back T key l 
-        let v <-
+        let l0 ← hashmap_hash_map_remove_from_list_back T key l
+        let v ←
           vec_index_mut_back (hashmap_list_t T) self.hashmap_hash_map_slots
-            hash_mod l0 
+            hash_mod l0
         Result.ret
           {
             hashmap_hash_map_num_entries := self.hashmap_hash_map_num_entries,
@@ -555,12 +538,12 @@ def hashmap_hash_map_remove_back
           }
     | Option.some x0 =>
       do
-        let i0 <- USize.checked_sub self.hashmap_hash_map_num_entries
-          (USize.ofNatCore 1 (by intlit)) 
-        let l0 <- hashmap_hash_map_remove_from_list_back T key l 
-        let v <-
+        let i0 ← USize.checked_sub self.hashmap_hash_map_num_entries
+          (USize.ofNatCore 1 (by intlit))
+        let l0 ← hashmap_hash_map_remove_from_list_back T key l
+        let v ←
           vec_index_mut_back (hashmap_list_t T) self.hashmap_hash_map_slots
-            hash_mod l0 
+            hash_mod l0
         Result.ret
           {
             hashmap_hash_map_num_entries := i0,
@@ -568,91 +551,90 @@ def hashmap_hash_map_remove_back
             hashmap_hash_map_max_load := self.hashmap_hash_map_max_load,
             hashmap_hash_map_slots := v
           }
-    
 
 /- [hashmap_main::hashmap::test1] -/
 def hashmap_test1_fwd : Result Unit :=
   do
-    let hm <- hashmap_hash_map_new_fwd UInt64 
-    let hm0 <-
+    let hm ← hashmap_hash_map_new_fwd UInt64
+    let hm0 ←
       hashmap_hash_map_insert_fwd_back UInt64 hm
-        (USize.ofNatCore 0 (by intlit)) (UInt64.ofNatCore 42 (by intlit)) 
-    let hm1 <-
+        (USize.ofNatCore 0 (by intlit)) (UInt64.ofNatCore 42 (by intlit))
+    let hm1 ←
       hashmap_hash_map_insert_fwd_back UInt64 hm0
-        (USize.ofNatCore 128 (by intlit)) (UInt64.ofNatCore 18 (by intlit)) 
-    let hm2 <-
+        (USize.ofNatCore 128 (by intlit)) (UInt64.ofNatCore 18 (by intlit))
+    let hm2 ←
       hashmap_hash_map_insert_fwd_back UInt64 hm1
-        (USize.ofNatCore 1024 (by intlit)) (UInt64.ofNatCore 138 (by intlit)) 
-    let hm3 <-
+        (USize.ofNatCore 1024 (by intlit)) (UInt64.ofNatCore 138 (by intlit))
+    let hm3 ←
       hashmap_hash_map_insert_fwd_back UInt64 hm2
-        (USize.ofNatCore 1056 (by intlit)) (UInt64.ofNatCore 256 (by intlit)) 
-    let i <-
-      hashmap_hash_map_get_fwd UInt64 hm3 (USize.ofNatCore 128 (by intlit)) 
-    if not (i = (UInt64.ofNatCore 18 (by intlit)))
+        (USize.ofNatCore 1056 (by intlit)) (UInt64.ofNatCore 256 (by intlit))
+    let i ←
+      hashmap_hash_map_get_fwd UInt64 hm3 (USize.ofNatCore 128 (by intlit))
+    if h: not (i = (UInt64.ofNatCore 18 (by intlit)))
     then Result.fail Error.panic
     else
       do
-        let hm4 <-
+        let hm4 ←
           hashmap_hash_map_get_mut_back UInt64 hm3
             (USize.ofNatCore 1024 (by intlit))
-            (UInt64.ofNatCore 56 (by intlit)) 
-        let i0 <-
+            (UInt64.ofNatCore 56 (by intlit))
+        let i0 ←
           hashmap_hash_map_get_fwd UInt64 hm4
-            (USize.ofNatCore 1024 (by intlit)) 
-        if not (i0 = (UInt64.ofNatCore 56 (by intlit)))
+            (USize.ofNatCore 1024 (by intlit))
+        if h: not (i0 = (UInt64.ofNatCore 56 (by intlit)))
         then Result.fail Error.panic
         else
           do
-            let x <-
+            let x ←
               hashmap_hash_map_remove_fwd UInt64 hm4
-                (USize.ofNatCore 1024 (by intlit)) 
-            match x with
+                (USize.ofNatCore 1024 (by intlit))
+            match h: x with
             | Option.none => Result.fail Error.panic
             | Option.some x0 =>
-              if not (x0 = (UInt64.ofNatCore 56 (by intlit)))
+              if h: not (x0 = (UInt64.ofNatCore 56 (by intlit)))
               then Result.fail Error.panic
               else
                 do
-                  let hm5 <-
+                  let hm5 ←
                     hashmap_hash_map_remove_back UInt64 hm4
-                      (USize.ofNatCore 1024 (by intlit)) 
-                  let i1 <-
+                      (USize.ofNatCore 1024 (by intlit))
+                  let i1 ←
                     hashmap_hash_map_get_fwd UInt64 hm5
-                      (USize.ofNatCore 0 (by intlit)) 
-                  if not (i1 = (UInt64.ofNatCore 42 (by intlit)))
+                      (USize.ofNatCore 0 (by intlit))
+                  if h: not (i1 = (UInt64.ofNatCore 42 (by intlit)))
                   then Result.fail Error.panic
                   else
                     do
-                      let i2 <-
+                      let i2 ←
                         hashmap_hash_map_get_fwd UInt64 hm5
-                          (USize.ofNatCore 128 (by intlit)) 
-                      if not (i2 = (UInt64.ofNatCore 18 (by intlit)))
+                          (USize.ofNatCore 128 (by intlit))
+                      if h: not (i2 = (UInt64.ofNatCore 18 (by intlit)))
                       then Result.fail Error.panic
                       else
                         do
-                          let i3 <-
+                          let i3 ←
                             hashmap_hash_map_get_fwd UInt64 hm5
-                              (USize.ofNatCore 1056 (by intlit)) 
-                          if not (i3 = (UInt64.ofNatCore 256 (by intlit)))
+                              (USize.ofNatCore 1056 (by intlit))
+                          if h: not (i3 = (UInt64.ofNatCore 256 (by intlit)))
                           then Result.fail Error.panic
                           else Result.ret ()
-            
 
 /- Unit test for [hashmap_main::hashmap::test1] -/
-#assert (hashmap_test1_fwd = .ret ())
+#assert (hashmap_test1_fwd == .ret ())
 
 /- [hashmap_main::insert_on_disk] -/
 def insert_on_disk_fwd
   (key : USize) (value : UInt64) (st : State) : Result (State × Unit) :=
   do
-    let (st0, hm) <- opaque_defs.hashmap_utils_deserialize_fwd st 
-    let hm0 <- hashmap_hash_map_insert_fwd_back UInt64 hm key value 
-    let (st1, _) <- opaque_defs.hashmap_utils_serialize_fwd hm0 st0 
+    let (st0, hm) ← opaque_defs.hashmap_utils_deserialize_fwd st
+    let hm0 ← hashmap_hash_map_insert_fwd_back UInt64 hm key value
+    let (st1, _) ← opaque_defs.hashmap_utils_serialize_fwd hm0 st0
     Result.ret (st1, ())
 
 /- [hashmap_main::main] -/
-def main_fwd : Result Unit := Result.ret ()
+def main_fwd : Result Unit :=
+  Result.ret ()
 
 /- Unit test for [hashmap_main::main] -/
-#assert (main_fwd = .ret ())
+#assert (main_fwd == .ret ())