and constant =
| CString of string
and goal = param_decl list * pattern list * expr list * code option
-and func = param_decl list * code
+and func = param_decl list * returning * code
and tactic = param_decl list * code
and param_decl = id (** goal/func/tactic parameter. *)
and id = string
-and code = substs
+and code = substs * bool (** code + quiet flag *)
+and returning = RetExpr | RetStrings | RetString
and substs = subst list
and subst =
| SString of string