/* $Id: rdfs.pro,v 1.1 2000/08/08 13:44:41 connolly Exp $ */
/* swi prolog debian package:
Package: swi-prolog
Status: install ok installed
Priority: optional
Section: interpreters
Installed-Size: 3368
Maintainer: Milan Zamazal <pdm@debian.org>
Version: 3.3.0beta9-5
Depends: libc6 (>= 2.1), libncurses5, libreadline4 (>= 4.1)
Description: Prolog interpreter.

  http://www.swi.psy.uva.nl/projects/SWI-Prolog/
*/
    
entails([M], P, S, O) :- says(M, P, S, O).

/* @@ short-hand junk */
label(Thing, Name) :- entails(_Msgs, 'http://www.w3.org/2000/01/rdf-schema#label', Thing, String), string_to_atom(String, Name).

type(I, C) :- entails(_Msgs, 'http://www.w3.org/1999/02/22-rdf-syntax-ns#type', I, C).


/* @@hmm... how to weaken these premises from says to entails */
/* go meta: says(rdf-spec, _rule_below_) */
entails(list_to_set([M1, M2]), Genl, S, O) :-
    says(M1, 'http://www.w3.org/2000/01/rdf-schema#subProperty', Specl, Genl),
    says(M2, Specl, S, O).

entails(list_to_set([M1, M2]), 'http://www.w3.org/1999/02/22-rdf-syntax-ns#type', I, Super) :-
    says(M1, 'http://www.w3.org/1999/02/22-rdf-syntax-ns#type', I, Sub),
    says(M2, 'http://www.w3.org/2000/01/rdf-schema#subClass', Sub, Super).

/* algernon backlink */
entails(list_to_set([M1, M2]), Rel, S, O) :- 
    says(M1, 'http://www.w3.org/2000/07/hs78/algernon#backlink', Rev, Rel),
    says(M2, Rev, O, S).

says(replyX,
     'http://www.w3.org/2000/07/hs78/algernon#backlink',
     'http:proposal43/proposal.rdf#forExample',
     'http://www.w3.org/1999/02/22-rdf-syntax-ns#type').


include('proposal.pro').