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Re: Common RDF parser bug?

From: David Allsopp <d.allsopp@signal.qinetiq.com>
Date: Mon, 21 Jan 2002 10:38:05 +0000
Message-ID: <3C4BEF8D.91EEAA8F@signal.qinetiq.com>
To: www-rdf-interest@w3.org

Jeremy Carroll wrote:
> >
> > I think the text from M&S is simply expressing a cardinality
> > constraint, part of the M&S (informal) ontology.  Therefor this
> > constraint should be handled when/if other ontology information is
> > handled, and not in the RDF parser.
> Hear, hear.
> ARP explicitly does not do any schema validation.
> I will *not* be adding this as a defect to ARP's bugzilla.

This does mean that anyone using an RDF parser to load an RDF-XML
document has no guarantee that the RDF is valid. It will certainly seem
counterintuitive to RDF newcomers that a conformant RDF parser will
allow invalid RDF.

It also seems from the replies that different approaches to such invalid
RDF will occur; some people may attempt to infer equivalences, as Sandro
suggests, but others could equally well reject the RDF as invalid after
detecting the wrong number of properties. Which approach is _correct_?
If there is more than one 'correct' approach, then the meaning of that
piece of RDF is ambiguous. I think this needs clarifying.


David Allsopp.

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Received on Monday, 21 January 2002 05:38:15 UTC

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