(* Copyright (C) 2004-2005, HELM Team.
 * 
 * This file is part of HELM, an Hypertextual, Electronic
 * Library of Mathematics, developed at the Computer Science
 * Department, University of Bologna, Italy.
 * 
 * HELM is free software; you can redistribute it and/or
 * modify it under the terms of the GNU General Public License
 * as published by the Free Software Foundation; either version 2
 * of the License, or (at your option) any later version.
 * 
 * HELM is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 * GNU General Public License for more details.
 *
 * You should have received a copy of the GNU General Public License
 * along with HELM; if not, write to the Free Software
 * Foundation, Inc., 59 Temple Place - Suite 330, Boston,
 * MA  02111-1307, USA.
 * 
 * For details, see the HELM World-Wide-Web page,
 * http://helm.cs.unibo.it/
 *)

module Ast = CicNotationPt

type tag = int
type pattern_t = Ast.term

let get_tag term0 =
  let subterms = ref [] in
  let map_term t =
    subterms := t :: !subterms ; 
    Ast.Implicit
  in
  let rec aux t = CicNotationUtil.visit_ast ~special_k map_term t
  and special_k = function
    | Ast.AttributedTerm (_, t) -> aux t
    | _ -> assert false
  in
  let term_mask = aux term0 in
  let tag = Hashtbl.hash term_mask in
  tag, List.rev !subterms