- From: Jeremy Carroll <jjc@hplb.hpl.hp.com>
- Date: Wed, 20 Mar 2002 11:32:04 -0000
- To: "Patrick Stickler" <patrick.stickler@nokia.com>, "Pat Hayes" <phayes@ai.uwf.edu>, "RDF Core" <w3c-rdfcore-wg@w3.org>
Pat: > >> Another possibility is to allow certain namespaces to be declared to > >> be dark, so that any triple using a property from a dark namespace is > >> considered to be unasserted. Again, this does not require any change > >> to the syntax, but only some extra conventions to be added to the > >> language. > >> Jeremy: > > This could be a namespace prefix rather than the namespace e.g. > > > > > > <rdf:RDF xmlns:eg="http://example.org/" > xmlns:egdark="http://example.org/" > > rdf:darkPrefixes="egdark"> > > <rdf:Description eg:aserted="foo" egd:unasserted="bar" /> > > > > </rdf:RDF> > > > > Jeremy Patrick: > This becomes problemmatic (in a practical sense) if we want to > use the same vocabularies for both asserted and unasserted > statements. A fair point ... my example is bad stylistically, but does show that the XML syntax is as flexible as the n-triple syntax. Patrick: > An alternative: > > How about an element rdf:Expression (or some such) which is in all > other ways identical to rdf:Description except that statements > are not asserted. E.g. > > <rdf:Expression rdf:about="#Bob> > <ex:age>35</ex:age> > </rdf:Expression> > > gives us > > :Bob ex:age "35" ; > or > - :Bob ex:age "35" . > > This doesn't require any significant changes to current parsers > and the only modification is to activate a flag when seeing > rdf:Expression rather than rdf:Description and add the non-asserted > punctuation when outputting the triples. This too is a fair syntax .... I suspect somewhat more confusing though ... We still can get the confusion of using the same vocab both ways ... e.g. <rdf:RDF> <rdf:Expression rdf:about="#Bob> <ex:age>35</ex:age> </rdf:Expression> <rdf:Description rdf:about="#April> <ex:age>35</ex:age> </rdf:Description> </rdf:RDF> and would need clarity about embedding e.g. <rdf:RDF> <rdf:Description rdf:about="#April> <ex:foo> <rdf:Expression rdf:about="#Bob> <ex:bar ex:doublyEmbedded="??"/> </rdf:Expression> </ex:foo> </rdf:Description> </rdf:RDF> that clarity could be done (I would favour a one level reading like for bagID). Jeremy
Received on Wednesday, 20 March 2002 06:33:34 UTC