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.
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.
12 * HELM is distributed in the hope that it will be useful,
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://www.cs.unibo.it/helm/.
26 (* AUTOR: Ferruccio Guidi <fguidi@cs.unibo.it>
29 (* output data structures ***************************************************)
31 type path = string list (* the name of an attribute *)
33 type value = string list (* the value of an attribute *)
35 type attribute = path * value (* an attribute *)
37 type attribute_group = attribute list (* a group of attributes *)
39 type attribute_set = attribute_group list (* the attributes of an URI *)
41 type resource = string * attribute_set (* an attributed URI *)
43 type resource_set = resource list (* the query result *)
45 type result = resource_set
48 (* input data structures ****************************************************)
50 type svar = string (* the name of a variable for a resource set *)
52 type avar = string (* the name of a variable for a resource *)
56 type refine = RefineExact
64 type exp = path * (path option)
66 type exp_list = exp list
74 type gen = GenFJoin (* full union - with attr handling *)
75 | GenFMeet (* full intersection - with attr handling *)
77 type query = Const of result
81 | Ex of avar list * query
82 | Select of avar * query * query
83 | Let of svar option * query * query
84 | Fun of path * path list * query list
85 | Gen of path * query list
86 | Add of bool * groups * query
87 | For of gen * avar * query * query
88 | While of gen * query * query
89 | Property of inverse * refine * path *
90 main * istrue * isfalse list * exp_list *
93 and groups = Attr of (path * query) list list
96 and con = pattern * path * query
100 and isfalse = con list