1/* Part of ClioPatria SeRQL and SPARQL server 2 3 Author: Jan Wielemaker 4 E-mail: J.Wielemaker@vu.nl 5 WWW: http://www.swi-prolog.org 6 Copyright (c) 2010-2018, University of Amsterdam, 7 VU University Amsterdam 8 All rights reserved. 9 10 Redistribution and use in source and binary forms, with or without 11 modification, are permitted provided that the following conditions 12 are met: 13 14 1. Redistributions of source code must retain the above copyright 15 notice, this list of conditions and the following disclaimer. 16 17 2. Redistributions in binary form must reproduce the above copyright 18 notice, this list of conditions and the following disclaimer in 19 the documentation and/or other materials provided with the 20 distribution. 21 22 THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS 23 "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT 24 LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS 25 FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE 26 COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, 27 INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, 28 BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; 29 LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER 30 CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT 31 LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN 32 ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE 33 POSSIBILITY OF SUCH DAMAGE. 34*/ 35 36:- module(rdfslite_entailment, 37 [ 38 ]). 39:- use_module(rdfql(rdfql_runtime)). % runtime tests 40:- use_module(library('semweb/rdf_db'), 41 [ rdf_global_id/2, 42 rdf_reachable/3, 43 rdf_has/3, 44 rdf_has/4, 45 rdf_subject/1, 46 rdf_equal/2, 47 (rdf_meta)/1, 48 op(_,_,_) 49 ]). 50:- use_module(library('semweb/rdfs'), 51 [ rdfs_subclass_of/2, 52 rdfs_subproperty_of/2, 53 rdfs_individual_of/2 54 ]). 55 56/** <module> RDFS-Lite entailment 57 58The function of an entailment module is to provide an implementation of 59rdf/3 that extends basic triple-lookup using the entailment rules of the 60semantic web sub language of RDF. 61 62This entailment module does the part of RDFS that can be implemented 63efficiently using backward chaining. Notably it does *not* do 64type-reasoning on the basis of domains/ranges of properties. It does: 65 66 * Use the property hierarchy 67 * Define the serql special relations 68 * Handle rdfs:subClassOf as transitive 69 * Handle rdfs:subPropertyOf as transitive 70 * Handle rdf:type using subProperties and rdfs:subClassOf 71*/ 72 73:- rdf_meta 74 rdf(o,o,o). 75 76:- public 77 rdf/3, 78 rdf/4. 79 80rdf(S, P, O) :- 81 var(P), 82 !, 83 rdf_db:rdf(S,P,O). 84rdf(S, serql:directSubClassOf, O) :- 85 !, 86 rdf_has(S, rdfs:subClassOf, O). 87rdf(S, serql:directType, O) :- 88 !, 89 rdf_has(S, rdf:type, O). 90rdf(S, serql:directSubPropertyOf, O) :- 91 !, 92 rdf_has(S, rdfs:subPropertyOf, O). 93rdf(S, rdfs:subClassOf, O) :- ( atom(S) ; atom(O) ), 94 !, 95 rdf_reachable(S, rdfs:subClassOf, O). 96rdf(S, rdfs:subClassOf, O) :- 97 !, 98 rdf_has(S, rdfs:subClassOf, Direct), 99 rdf_reachable(Direct, rdfs:subClassOf, O). 100rdf(S, rdfs:subPropertyOf, O) :- 101 !, 102 rdf_reachable(S, rdfs:subPropertyOf, O). 103rdf(S, rdf:type, O) :- 104 !, 105 ( var(S), var(O) 106 -> rdf_subject(S) 107 ; true 108 ), 109 rdfs_individual_of(S, O). 110rdf(S, P, O) :- 111 rdf_has(S, P, O). 112 113%! rdf(?S, ?P, ?O, ?G) 114 115rdf(S, P, O, G) :- 116 var(P), 117 !, 118 rdf_db:rdf(S, P, O, G). 119rdf(S, P, O, G) :- 120 rdf_has(S, P, O, RP), 121 rdf_db:rdf(S, RP, O, G). 122 123 /******************************* 124 * REGISTER * 125 *******************************/ 126 127:- multifile 128 cliopatria:entailment/2. 129 130cliopatriaentailment(rdfslite, rdfslite_entailment)