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Need a decision (was: Re: namedNode? in predicate position?)

From: pat hayes <phayes@ai.uwf.edu>
Date: Tue, 4 Sep 2001 12:25:08 -0700
Message-Id: <v04210104b7bad8d1f211@[130.107.66.237]>
To: w3c-rdfcore-wg@w3.org
Dave Beckett <dave.beckett@bristol.ac.uk>
> >>>Art Barstow said:
>
><snip/>
>
> > I like the idea of allowing predicates to be princeNodes
> > because it would eliminate special casing predicates (and simplify
> > N-Triples a little).  However, I agree with Dave's position (although
> > M&S is not explicit on this) and thus have written some apps that
> > assume predicates will be URI-refs and not princeNodes.
>
>I don't have any problem with the change - just to note it *is* a
>change and we should take care that if we do this, we have good
>reasons and consider what the change causes deployed applications.
>
>The current RDF/XML syntax cannot generate any model with non-URI-ref
>predicates (unless you reify) thus that means some models can be
>created that can not be transfered in the standard RDF/XML syntax
>(although this is true for other models too).
>
>For evidence on implementation: my Redland system has no problem
>handling princeNode predicates.

Please let us get this decided as quickly as possible, as if we allow 
anonymous properties then I should change the MT back to apply 
directly to N-triples rather than to RDF graphs, since not all 
N-triples documents will be graphs, and in any case (as outlined in 
my reply to Aaron), the advantages of the graph syntax would be lost 
if we make this change, so it would be better to return to a more 
conventional notion of syntax.

In fact if we do make this change, I would urge that we decide that 
some kind of N-triplish syntax be adopted as the primary RDF syntax 
(though preferably with an explicit notion of syntactic scope), and 
abandon the 'RDF graph' idea as simply misleading, largely for the 
reasons Aaron suggests.

I will put off further work on the MT document until this issue is decided.

Pat Hayes

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Received on Tuesday, 4 September 2001 15:23:51 EDT

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