1 (* Copyright (C) 2005, HELM Team.
3 * This file is part of HELM, an Hypertextual, Electronic
4 * Library of Mathematics, developed at the Computer Science
5 * Department, University of Bologna, Italy.
7 * HELM is free software; you can redistribute it and/or
8 * modify it under the terms of the GNU General Public License
9 * as published by the Free Software Foundation; either version 2
10 * of the License, or (at your option) any later version.
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13 * but WITHOUT ANY WARRANTY; without even the implied warranty of
14 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
15 * GNU General Public License for more details.
17 * You should have received a copy of the GNU General Public License
18 * along with HELM; if not, write to the Free Software
19 * Foundation, Inc., 59 Temple Place - Suite 330, Boston,
22 * For details, see the HELM World-Wide-Web page,
23 * http://helm.cs.unibo.it/
26 type coerc_carr = Uri of UriManager.uri | Sort of Cic.sort | Term of Cic.term
27 exception EqCarrNotImplemented of string Lazy.t
28 exception EqCarrOnNonMetaClosed
31 let use_coercions = ref true
33 let coerc_carr_of_term t =
35 Uri (CicUtil.uri_of_term t)
36 with Invalid_argument _ ->
38 | Cic.Sort s -> Sort s
44 | Uri src, Uri tgt -> UriManager.eq src tgt
45 | Sort (Cic.Type _), Sort (Cic.Type _) -> true
46 | Sort src, Sort tgt when src = tgt -> true
48 if CicUtil.is_meta_closed t1 && CicUtil.is_meta_closed t2 then
51 (lazy ("Unsupported carr for coercions: " ^
52 CicPp.ppterm t1 ^ " or " ^ CicPp.ppterm t2)))
53 else raise EqCarrOnNonMetaClosed
56 let name_of_carr = function
57 | Uri u -> UriManager.name_of_uri u
58 | Sort s -> CicPp.ppsort s
59 | Term t -> CicPp.ppterm t
68 let remove_coercion p =
69 db := List.filter (fun u -> not(p u)) !db
72 if !use_coercions then
73 List.map (fun (_,_,x) -> x) (List.filter (fun (s,t,_) -> f (s,t)) !db)