1 (* Copyright (C) 2003-2005, 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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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://cs.unibo.it/helm/.
29 module PEH = ProofEngineHelpers
31 type conclusion = (int * int) option
33 (* debugging ****************************************************************)
35 let string_of_entry inverse =
36 if I.S.mem 0 inverse then "C" else
37 if I.S.is_empty inverse then "I" else "P"
39 let to_string (classes, rc) =
40 let linearize = String.concat " " (List.map string_of_entry classes) in
43 | Some (i, j) -> Printf.sprintf "%s %u %u" linearize i j
46 let map i (_, inverse) =
47 let map i tl = Printf.sprintf "%2u" i :: tl in
48 let iset = String.concat " " (I.S.fold map inverse []) in
49 Printf.eprintf "%2u|%s\n" i iset
54 (****************************************************************************)
58 let classify_conclusion = function
59 | _, C.Rel i -> Some (i, 0)
60 | _, C.Appl (C.Rel i :: tl) -> Some (i, List.length tl)
65 let vs, h = PEH.split_with_whd (c, t) in
66 let rc = classify_conclusion (List.hd vs) in
67 let map (b, h) (_, v) = (I.get_rels_from_premise h v, I.S.empty) :: b, succ h in
68 let l, h = List.fold_left map ([], 0) vs in
69 let b = Array.of_list (List.rev l) in
71 let map j = if j < h then I.S.union (fst b.(j)) else id in
72 for i = pred h downto 0 do
73 let direct, unused = b.(i) in
74 b.(i) <- I.S.fold map direct direct, unused
77 let b = mk_closure b h in
78 let rec mk_inverse i direct =
79 if I.S.is_empty direct then () else
80 let j = I.S.choose direct in
82 let unused, inverse = b.(j) in
83 b.(j) <- unused, I.S.add i inverse
85 mk_inverse i (I.S.remove j direct)
87 let map i (direct, _) = mk_inverse i direct in
90 List.rev_map snd (List.tl (Array.to_list b)), rc
91 with Invalid_argument _ -> failwith "Classify.classify"