- From: Jos De_Roo <jos.deroo@agfa.com>
- Date: Fri, 22 Aug 2003 18:50:15 +0200
- To: "Jan Grant <Jan.Grant" <Jan.Grant@bristol.ac.uk>
- Cc: Dan Brickley <danbri@w3.org>, rdfcore-in-exile <rdfcore-in-exile@vapours.rdfweb.org>, rdfcore-in-exile-bounces@vapours.rdfweb.org, w3c-rdfcore-wg@w3.org
Jan - it is right that in our current implementation [[ eg:foo eg:bar "10"^^xsd:integer . ]] rdfs+dt(xsd:integer, xsd:decimal) - entails [[ eg:foo eg:bar "10.0"^^xsd:decimal . ]] and also the other way around; we did that in a builtin way [[ if (obj != null && verb == "^^" && t.verb == "^^" && subj.bound && t.subj.bound && (obj.unify(t.obj, r, s) || Datatype.isNumeric(obj.deref().verb) && Datatype.isNumeric(t.obj.deref().verb))) return Datatype.compare(obj.deref().verb, r.getLit(this), r.getLit(t)) == 0; ]] and where Datatype.compare is using Xerces or .NET functionality but maybe we went too far... -- Jos De Roo, AGFA http://www.agfa.com/w3c/jdroo/ Jan Grant <Jan.Grant@bristol.ac.uk> To: Dan Brickley <danbri@w3.org> Sent by: cc: rdfcore-in-exile <rdfcore-in-exile@vapours.rdfweb.org>, w3c-rdfcore-wg@w3.org rdfcore-in-exile-bounces@vapours Subject: Re: [rdfcore-in-exile] Agenda for 2003-08-22 RDFCore telecon (1hr) .rdfweb.org 2003-08-22 03:03 PM On Fri, 22 Aug 2003, Dan Brickley wrote: > 12: Treatment of XSD types > > thread spun off http://lists.w3.org/Archives/Public/w3c-rdfcore-wg/2003Aug/0231.html > > [[ > Hopefully for Pat to just confirm that I didn't imagine it when I > thought I heard him say that this is now the treatment of XSD types: ie, > that their denotation is a pair of (typename, value). > ]] --Jan > > [[ > xsd:integer is still a subclass of xsd:decimal (which may or may not be > true with intentional semantics, regardless of the datatype L2V > definition); or rather, the value space of one is a subset of the value > space of the other (in which case nothing needs doing), or: > > xsd:integer's value space is not a subset of the value space of > xsd:decimal after all, in which case I add another "What?!?" to the > list, but that's a problem to raise with the xml schema people. > ]] -- JanG > > [[ > Yup; when Pat said, "none of the XSD datatypes intersect", he meant, > with the value space for XML Literal, not each other. Sorry if I gave > anyone heartaches over their cornflakes. > ]] > JanG, http://lists.w3.org/Archives/Public/w3c-rdfcore-wg/2003Aug/0241.html > > Is this resolved / closed / understood now? Any affect on specs? Actually, from the sound of PatH's followup, this might not be resolved. Anyway, currently we have the test case: http://www.w3.org/2000/10/rdf-tests/rdfcore/datatypes/Manifest.rdf#semantic-equivalence-between-datatypes which says that [[ eg:foo eg:bar "10"^^xsd:integer . ]] rdfs+dt(xsd:integer, xsd:decimal) - entails [[ eg:foo eg:bar "10.0"^^xsd:decimal . ]] The test case is useful in that it illustrates that two members of different datatypes may indeed denote the same value. It also expresses our best understanding at the time of the intention of the XSD spec. Finally, in support of this test case, as I recall WebOnt passed a resolution to the effect that (amongst other things) xsd:integer was a subclass of xsd:decimal (wrt value spaces). I don't know if that resolution is out-of-date. However: - the test case actually tests another spec - while it sounds like XMLSchema are prepping words which will probably (due to equality/identity distinction) preserve the truth of this test case by a gnat's whisker, - ... the truth of this test case is not "obvious" since the XSD WG, if not the spec itself, seem to be in two minds about it. Thus there are three options: 1. Preserve the test case as is. In that case, we should probably communicate to the XML Schema WG asking them to consider it as identifying a strong use case should they come to revise their decisions wrt the value sapces of XSD primitive types; 2. Remove it on the grounds that (a) it's not our problem, (b) the truth of it depends on another WG's decisions 3. Label the test case as being non-normative, whilst approved, since (a) it illustrates a valid point about the value spaces of datatyped literals, regardless of the XSD details, (b) we think this is how XSD primitive types should work in RDF, and again ask the XML Schema WG to bear it in mind. In that case the test case document would include some words about this test case to the effect that the XSD types are used purely to ground in concrete terms the illustrative test case. We already have implementations (Jos?) that pass this test case. -- jan grant, ILRT, University of Bristol. http://www.ilrt.bris.ac.uk/ Tel +44(0)117 9287088 Fax +44 (0)117 9287112 http://ioctl.org/jan/ That which does not kill us goes straight to our thighs. _______________________________________________ rdfcore-in-exile mailing list rdfcore-in-exile@vapours.rdfweb.org http://rdfweb.org/mailman/listinfo/rdfcore-in-exile
Received on Friday, 22 August 2003 21:33:38 UTC