-(* Copyright (C) 2006, 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/
- *)
-
-type 'a t = ('a, int ref) Hashtbl.t
-
-let create () = Hashtbl.create 113
-
-let incr ~create_cb counters item =
- try
- let counter = Hashtbl.find counters item in
- incr counter
- with Not_found ->
- Hashtbl.add counters item (ref 1);
- create_cb item
-
-let decr ~delete_cb counters item =
- try
- let counter = Hashtbl.find counters item in
- decr counter;
- if !counter = 0 then begin
- Hashtbl.remove counters item;
- delete_cb item
- end
- with Not_found ->
- prerr_endline "RefCounter: attempt to decrease unexistent counter";
- assert false
-