---

yaml
---
r: 821
b: refs/heads/master
c: 194f38f
h: refs/heads/master
i:
  819: 22fee94
v: v3

Author: pcwalton

[refs]

@@ -1,2 +1,2 @@
 ---
-refs/heads/master: a7840f02b0eb3d4247c66e5169f7f50e19e70d6d
+refs/heads/master: 194f38fdff2b2067413b6eabf3d6da57fbba2dc1

trunk/src/boot/fe/ast.ml

@@ -516,6 +516,17 @@ let sane_name (n:name) : bool =
       | NAME_ext (prefix, _) -> sane_prefix prefix
 ;;
 
+(* Error messages always refer to simple types structurally, not by their
+ * user-defined names. *)
+let rec ty_is_simple (ty:ty) : bool =
+  match ty with
+      TY_any | TY_nil | TY_bool | TY_mach _ | TY_int | TY_uint | TY_char
+    | TY_str | TY_task | TY_type -> true
+    | TY_vec ty | TY_chan ty | TY_port ty -> ty_is_simple ty
+    | TY_tup tys -> List.for_all ty_is_simple (Array.to_list tys)
+    | _ -> false
+;;
+
 (*
  * We have multiple subset-categories of expression:
  *

trunk/src/boot/me/semant.ml

@@ -971,7 +971,7 @@ let ty_fold_rebuild (id:Ast.ty -> Ast.ty)
 
 let rec pretty_ty_str (cx:ctxt) (fallback:(Ast.ty -> string)) (ty:Ast.ty) =
   let cache = cx.ctxt_user_type_names in
-  if Hashtbl.mem cache ty then
+  if not (Ast.ty_is_simple ty) && Hashtbl.mem cache ty then
     let names = List.map (Ast.sprintf_name ()) (Hashtbl.find_all cache ty) in
     String.concat " = " names
   else