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Re: Unasserted triples, Contexts and things that go bump in the night.

From: Patrick Stickler <patrick.stickler@nokia.com>
Date: Wed, 20 Mar 2002 13:17:45 +0200
To: Jeremy Carroll <jjc@hplb.hpl.hp.com>, Pat Hayes <phayes@ai.uwf.edu>, RDF Core <w3c-rdfcore-wg@w3.org>
Message-ID: <B8BE3C79.111C6%patrick.stickler@nokia.com>
On 2002-03-20 12:38, "ext Jeremy Carroll" <jjc@hplb.hpl.hp.com> wrote:


>> Another possibility is to allow certain namespaces to be declared to
>> be dark, so that any triple using a property from a dark namespace is
>> considered to be unasserted. Again, this does not require any change
>> to the syntax, but only some extra conventions to be added to the
>> language. 
>> 
> 
> This could be a namespace prefix rather than the namespace e.g.
> 
> 
> <rdf:RDF xmlns:eg="http://example.org/" xmlns:egdark="http://example.org/"
>        rdf:darkPrefixes="egdark">
>    <rdf:Description eg:aserted="foo" egd:unasserted="bar" />
> 
> </rdf:RDF>
> 
> Jeremy

This becomes problemmatic (in a practical sense) if we want to
use the same vocabularies for both asserted and unasserted
statements.

An alternative:

How about an element rdf:Expression (or some such) which is in all
other ways identical to rdf:Description except that statements
are not asserted. E.g.

   <rdf:Expression rdf:about="#Bob>
      <ex:age>35</ex:age>
   </rdf:Expression>

gives us

    :Bob ex:age "35" ;
or
    - :Bob ex:age "35" .

This doesn't require any significant changes to current parsers
and the only modification is to activate a flag when seeing
rdf:Expression rather than rdf:Description and add the non-asserted
punctuation when outputting the triples.

Eh?

Patrick

--
               
Patrick Stickler              Phone: +358 50 483 9453
Senior Research Scientist     Fax:   +358 7180 35409
Nokia Research Center         Email: patrick.stickler@nokia.com
Received on Wednesday, 20 March 2002 06:15:36 EST

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