Make minor modifications

3 files changed, 10 insertions, 8 deletions

diff --git a/src/Names.ml b/src/Names.ml
index a57f9aa1..1308eccc 100644
--- a/src/Names.ml
+++ b/src/Names.ml
@@ -72,3 +72,11 @@ let as_ident (pe : path_elem) : string =
   match pe with
   | Ident s -> s
   | Disambiguator _ -> raise (Failure "Improper variant")
+
+let path_elem_to_string (pe : path_elem) : string =
+  match pe with
+  | Ident s -> s
+  | Disambiguator d -> "{" ^ Disambiguator.to_string d ^ "}"
+
+let name_to_string (name : name) : string =
+  String.concat "::" (List.map path_elem_to_string name)
diff --git a/src/Print.ml b/src/Print.ml
index fedc4122..8df3001f 100644
--- a/src/Print.ml
+++ b/src/Print.ml
@@ -11,13 +11,7 @@ module M = Modules
 let option_to_string (to_string : 'a -> string) (x : 'a option) : string =
   match x with Some x -> "Some (" ^ to_string x ^ ")" | None -> "None"
 
-let path_elem_to_string (pe : path_elem) : string =
-  match pe with
-  | Ident s -> s
-  | Disambiguator d -> "{" ^ Disambiguator.to_string d ^ "}"
-
-let name_to_string (name : name) : string =
-  String.concat "::" (List.map path_elem_to_string name)
+let name_to_string (name : name) : string = Names.name_to_string name
 
 let fun_name_to_string (name : fun_name) : string = name_to_string name
 
diff --git a/src/Substitute.ml b/src/Substitute.ml
index 7cb0e8c2..c76f1da4 100644
--- a/src/Substitute.ml
+++ b/src/Substitute.ml
@@ -121,7 +121,7 @@ let type_decl_get_instantiated_variants_fields_rtypes (def : T.type_decl)
           variants
     | T.Struct fields -> [ (None, fields) ]
     | T.Opaque ->
-        raise (Failure "Can't retrieve the variants of an opaque type")
+        raise (Failure ("Can't retrieve the variants of an opaque type: " ^ Names.name_to_string def.name))
   in
   List.map
     (fun (id, fields) ->