1 (* Copyright (C) 2000, 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.
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9 * as published by the Free Software Foundation; either version 2
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15 * GNU General Public License for more details.
17 * You should have received a copy of the GNU General Public License
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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/.
26 (* AUTOR: Ferruccio Guidi <fguidi@cs.unibo.it>
29 (* boolean constants *******************************************************)
33 let mql_true = ["", []]
35 (* set theoretic operations *************************************************)
37 let rec set_sub v1 v2 =
41 | (h1, _) :: _, (h2, _) :: _ when h1 < h2 -> mql_false
42 | (h1, _) :: _, (h2, _) :: t2 when h1 > h2 -> set_sub v1 t2
43 | _ :: t1, _ :: t2 -> set_sub t1 t2
45 let rec set_meet v1 v2 =
49 | (h1, _) :: t1, (h2, _) :: _ when h1 < h2 -> set_meet t1 v2
50 | (h1, _) :: _, (h2, _) :: t2 when h1 > h2 -> set_meet v1 t2
53 let rec set_eq v1 v2 =
56 | (h1, _) :: t1, (h2, _) :: t2 when h1 = h2 -> set_eq t1 t2
59 let rec set_union v1 v2 =
63 | h1 :: t1, h2 :: t2 when h1 < h2 -> h1 :: set_union t1 v2
64 | h1 :: t1, h2 :: t2 when h1 > h2 -> h2 :: set_union v1 t2
65 | h1 :: t1, _ :: t2 -> h1 :: set_union t1 t2
67 let rec set_intersect v1 v2 =
71 | h1 :: t1, h2 :: _ when h1 < h2 -> set_intersect t1 v2
72 | h1 :: _, h2 :: t2 when h1 > h2 -> set_intersect v1 t2
73 | h1 :: t1, _ :: t2 -> h1 :: set_intersect t1 t2
75 let rec iter f = function
77 | head :: tail -> set_union (f head) (iter f tail)
79 (* MathQL specific set operations ******************************************)
81 let mql_subj v = List.map (fun s -> (s, [])) v
83 let rec mql_union s1 s2 =
87 | (r1, g1) :: t1, (r2, _) :: _ when r1 < r2 ->
88 (r1, g1) :: mql_union t1 s2
89 | (r1, _) :: _, (r2, g2) :: t2 when r1 > r2 ->
90 (r2, g2) :: mql_union s1 t2
91 | (r1, g1) :: t1, (_, g2) :: t2 ->
92 (r1, set_union g1 g2) :: mql_union t1 t2
94 let rec mql_iter f = function
96 | head :: tail -> mql_union (f head) (mql_iter f tail)
98 let rec mql_iter2 f l1 l2 = match l1, l2 with
100 | h1 :: t1, h2 :: t2 -> mql_union (f h1 h2) (mql_iter2 f t1 t2)
101 | _ -> raise (Invalid_argument "mql_iter2")
103 let rec mql_prod g1 g2 =
104 let mql_prod_aux a = iter (fun h -> [mql_union a h]) g2 in
107 let rec mql_intersect s1 s2 =
111 | (r1, _) :: t1, (r2, _) :: _ when r1 < r2 -> mql_intersect t1 s2
112 | (r1, _) :: _, (r2, _) :: t2 when r1 > r2 -> mql_intersect s1 t2
113 | (r1, g1) :: t1, (_, g2) :: t2 ->
114 (r1, set_intersect g1 g2) :: mql_intersect t1 t2
116 let rec mql_diff s1 s2 =
120 | (r1, g1) :: t1 , (r2, _) ::_ when r1 < r2 ->
121 (r1, g1) :: (mql_diff t1 s2)
122 | (r1, _) :: _, (r2, _) :: t2 when r1 > r2 -> mql_diff s1 t2
123 | _ :: t1, _ :: t2 -> mql_diff t1 t2
125 (* logic operations ********************************************************)
128 let b = v1 <> mql_false in
129 if b && v2 <> mql_false then mql_false else
132 (* numeric operations *******************************************************)
134 exception NumberError of MathQL.result
138 | [s, _] -> MQueryUtil.int_of_string s
139 | _ -> raise (Failure "int_of_string")
140 with Failure "int_of_string" -> raise (NumberError r)