Re: GUIDE: small comment on WD

From: Guus Schreiber <schreiber@swi.psy.uva.nl>
Subject: GUIDE: small comment on WD
Date: Fri, 15 Nov 2002 17:14:27 +0100

> We came across the following problerm.
> In the Guide the follwoing example [1] is given of "oneOf":
> 
> <owl:Class rdf:ID="WineColor">
>    <rdfs:subClassOf rdf:resource="#WineDescriptor"/>
>    <owl:oneOf rdf:parseType="Collection">
>      <owl:Thing rdf:about="#White"/>
>      <owl:Thing rdf:about="#Rose"/>
>      <owl:Thing rdf:about="#Red"/>
>    </owl:oneOf>
> </owl:Class>
> 
> Our parser has problems with this. The RDF Syntax doc appears to say 
> this is not the right syntax [2]. Collections should consist of node 
> elements, e.g.:
> 
>    <rdf:Description rdf:about="#White"/>
> 
> Correct?

Not correct, at least as far as I can determine.  An RDF node element,
which is what the owl:Thing nodes are, is a major syntactic category for
RDF.  In particular, the relevant section, 7.2.11, of the RDF syntax doc
specifically indicates that URIs other than rdf:Description are allowed,
and handled appropriately.

The part of the RDF syntax doc that you reference is *informational* only.
Any attempt to determine what is and what is not legal RDF should not use
this section.  (There was discussion in the RDF Core WG on this issue,
perhaps this misunderstanding should be brought forward as another point
against Section 2.)

> A minor point is that in the wine.owl file <owl:Item> is used instaed of 
> <owl:Thing>.
> 
> Guus
> 
> [1]
> http://www.w3.org/TR/2002/WD-owl-guide-20021104/#EnumeratedClasses
> [2]
> http://www.w3.org/TR/2002/WD-rdf-syntax-grammar-20021108/#section-Syntax-parsetype-Collection
> 
> -- 
> A. Th. Schreiber, SWI, University of Amsterdam,
> http://www.swi.psy.uva.nl/usr/Schreiber/home.html

peter

Received on Friday, 15 November 2002 11:50:44 UTC