2 (* Copyright (C) 2002, HELM Team.
4 * This file is part of HELM, an Hypertextual, Electronic
5 * Library of Mathematics, developed at the Computer Science
6 * Department, University of Bologna, Italy.
8 * HELM is free software; you can redistribute it and/or
9 * modify it under the terms of the GNU General Public License
10 * as published by the Free Software Foundation; either version 2
11 * of the License, or (at your option) any later version.
13 * HELM is distributed in the hope that it will be useful,
14 * but WITHOUT ANY WARRANTY; without even the implied warranty of
15 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
16 * GNU General Public License for more details.
18 * You should have received a copy of the GNU General Public License
19 * along with HELM; if not, write to the Free Software
20 * Foundation, Inc., 59 Temple Place - Suite 330, Boston,
23 * For details, see the HELM World-Wide-Web page,
24 * http://cs.unibo.it/helm/.
27 exception Uwobo_failure of string
29 val supported_properties: string list
30 val is_supported_property: string -> bool
35 (** execute 'action' in mutual exclusion between all other threads *)
36 method private doCritical: 'a lazy_t -> 'a
38 (** execute 'action' acting as a 'reader' i.e.: multiple readers can act
39 at the same time but no writer can act until no readers are acting *)
40 method private doReader: 'a lazy_t -> 'a
42 (** execute 'action' acting as a 'writer' i.e.: when a writer is acting,
43 no readers or writer can act, beware that writers can starve *)
44 method private doWriter: 'a lazy_t -> 'a