diff --git a/compiler/global/global_printer.ml b/compiler/global/global_printer.ml
index 814895c..a009006 100644
--- a/compiler/global/global_printer.ml
+++ b/compiler/global/global_printer.ml
@@ -48,7 +48,8 @@ and print_type ff = function
   | Tid id -> print_qualname ff id
   | Tarray (ty, n) ->
       fprintf ff "@[<hov2>%a^%a@]" print_type ty print_static_exp n
-  | Tunit -> fprintf ff "()"
+  | Tunit -> fprintf ff "unit"
+
 
 let print_field ff field =
   fprintf ff "@[%a: %a@]" print_qualname field.f_name  print_type field.f_type
diff --git a/compiler/global/types.ml b/compiler/global/types.ml
index c2832b0..d23b0a9 100644
--- a/compiler/global/types.ml
+++ b/compiler/global/types.ml
@@ -35,7 +35,7 @@ and ty =
 let invalid_type = Tprod []
 
 let prod = function
-  | []      -> assert false
+  | []      -> Tunit
   | [ty]    -> ty
   | ty_list -> Tprod ty_list