Re: pfps-04

From: pat hayes <phayes@ihmc.us>
Subject: Re: pfps-04
Date: Wed, 23 Jul 2003 14:56:07 -0500

> >From: Brian McBride <bwm@hplb.hpl.hp.com>
> >Subject: pfps-04
> >Date: 21 Jul 2003 14:22:45 +0100
> >
> >>  Peter,
> >>
> >>  with reference to your comment recorded as
> >>
> >>  http://www.w3.org/2001/sw/RDFCore/20030123-issues/#pfps-04
> >>
> >>  the RDFCore WG has resolved to accept your comment.
> >>
> >>  http://lists.w3.org/Archives/Public/w3c-rdfcore-wg/2003Jul/0173.html
> >>
> >>  As you know, there have been extensive modifications to the RDF
> >>  entailment rules since your comment was written
> >>
> >>  The current editor's draft, which is now stable enough to review,
> >>
> >>  http://www.w3.org/2001/sw/RDFCore/TR/WD-rdf-mt-20030117/
> >>
> >>  now contains a version of the RDF entailment rules which we believe
> >>  corresponds directly to the RDF semantic conditions in the sense
> >>  described. You can check the proof contained in the specification.
> >>
> >>  Please reply to this message, copying www-rdf-comments@w3.org,
> >>  indicating whether this response adequately addresses your comment.
> >>
> >>  Brian
> >
> >
> >There is still a mismatch between the RDF Entailment Rules, which, if
> >complete, determine that XML Literals are not the same as strings
> 
> ?? How can they possible determine that? Please explain.
> 
> Pat

[The following assumes that certain aspects of the RDF model theory will be
fixed up appropriately.]

Let x be any well-typed XML literal string.  Then "xx"^^rdf:XMLLiteral,
where xx is the appropriate encoding of x, has the same denotation in every
interpretation of a vocabulary that includes "xx"^^rdf:XMLLiteral, namely
the canonical XML object corresponding to x.  Let this object be x'.

If x' is a string then  
	ex:a ex:p x^^rdf:XMLLiteral .
rdf-entails 
	ex:a ex:p "xx'" .
where xx' is the n-triple encoding of x'.

Therefore for the RDF entailment rules to be complete, no XML Literal can
have a character string as its denotation.

Peter F. Patel-Schneider 
Bell Labs Research

Received on Wednesday, 23 July 2003 18:03:31 UTC