Minor refactoring

types/patterns.ml

@@ -80,20 +80,10 @@ let print_node ppf n =
   to_print := n :: !to_print;
   dump_print ppf
 
-let print_lst f ppf l =
-  let rec aux ppf = function
-    |[] -> Format.fprintf ppf "@."
-    |[h] -> Format.fprintf ppf "%a" f h
-    |h::t -> Format.fprintf ppf "%a,%a" f h aux t
-  in
-  match l with
-    |[] -> Format.fprintf ppf ""
-    |_ -> Format.fprintf ppf "%a" aux l
-
 let pp_v ppf (id, name) =
   Format.fprintf ppf "(%d,%s)" (Upool.int id) (Encodings.Utf8.to_string name)
 
-let pp_fv ppf fv = print_lst pp_v ppf fv
+let pp_fv ppf fv = Utils.pp_list ~delim:("","") pp_v ppf fv
 
 let pp_node ppf node =
   Format.fprintf ppf "id:%d; descr:[%a]; accept:[id:%d; descr:%a]; fv:[%a]"