1 files changed, 34 insertions, 0 deletions
diff --git a/src/PureUtils.ml b/src/PureUtils.ml
index b87a6346..873931be 100644
--- a/src/PureUtils.ml
+++ b/src/PureUtils.ml
@@ -478,3 +478,37 @@ let destruct_arrow (ty : ty) : ty * ty =
   | _ -> raise (Failure "Unreachable")
 
 let mk_arrow (ty0 : ty) (ty1 : ty) : ty = Arrow (ty0, ty1)
+
+let get_switch_body_ty (sb : switch_body) : ty =
+  match sb with
+  | If (e_then, _) -> e_then.ty
+  | Match branches ->
+      (* There should be at least one branch *)
+      (List.hd branches).branch.ty
+
+let map_switch_body_branches (f : texpression -> texpression) (sb : switch_body)
+    : switch_body =
+  match sb with
+  | If (e_then, e_else) -> If (f e_then, f e_else)
+  | Match branches ->
+      Match
+        (List.map
+           (fun (b : match_branch) -> { b with branch = f b.branch })
+           branches)
+
+let iter_switch_body_branches (f : texpression -> unit) (sb : switch_body) :
+    unit =
+  match sb with
+  | If (e_then, e_else) ->
+      f e_then;
+      f e_else
+  | Match branches -> List.iter (fun (b : match_branch) -> f b.branch) branches
+
+let mk_switch (scrut : texpression) (sb : switch_body) : texpression =
+  (* TODO: check the type of the scrutinee *)
+  let ty = get_switch_body_ty sb in
+  (* Sanity check: all the branches have the same type *)
+  iter_switch_body_branches (fun e -> assert (e.ty = ty)) sb;
+  (* Put together *)
+  let e = Switch (scrut, sb) in
+  { e; ty }