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Re: silly question about rdf:about

From: Dave Beckett <dave.beckett@bristol.ac.uk>
Date: Sun, 07 Apr 2002 18:58:36 +0100
To: Sandro Hawke <sandro@w3.org>
cc: www-rdf-interest@w3.org
Message-ID: <8684.1018202316@tatooine.ilrt.bris.ac.uk>
>>>Sandro Hawke said:
> 
> Why is rdf:about treated as magic syntax?  Wouldn't everything work
> the same in the grammar if
> http://www.w3.org/1999/02/22-rdf-syntax-ns#about were just another
> property?

The RDF/XML syntax would generate the same graph with this change
 
> Processors could either be hard-coded to know it was a
> daml:UnambiguousProperty (thus allowing the usual collapsing of nodes)
> or they could read that from the ontology.    (Obviously DAML is not
> part of RDF Core, but the concept of unambiguous properties is still
> around.)

There is no definition of an rdf processor, or an rdf processing
model.  We (RDF Core WG) certainly aren't adding requirement to
handle DAML or any other schema processing to an application that
reads RDF/XML and generates a graph.

Although having a daml:UnambiguousProperty feature around would be
very useful, it would be best to have this available to *all*
properties than adding special case magic for a particular property
in the RDF namespace.

> This interpretation would allow uses like:
> 
>   <rdf:Description>
>      <rdf:about>http://example.com</rdf:about>
>   </rdf:Description>
> 
> and declaring sub-properties of rdf:about to help classify kinds of
> names for things.   It would also allow zero or more names for things,
> which seems perfectly appropriate.

Zero names are already allowed:
  <rdf:Description>
     ...
  <rdf:Description/>

and subProperties requires an RDF-Schema-aware RDF system.

I suspect multiple 'names for things' is a large rat hole.  Insert
the usual URI-resource thread here.

This also potentially causes some unknown amount of changes to the
RDF model theory since a node can now have multiple URI labels.  If
you have worked them all out, please include them :)

Dave
Received on Sunday, 7 April 2002 13:58:41 GMT

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