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Re: name of rdf:nodeID attribute

From: Garret Wilson <garret@globalmentor.com>
Date: Tue, 14 Jan 2003 11:40:06 -0800
Message-ID: <3E246796.7000309@globalmentor.com>
To: Dave Beckett <dave.beckett@bristol.ac.uk>
CC: www-rdf-comments@w3.org

Dave,

Dave Beckett wrote:
>>>>Garret Wilson said:
>><rdf:Description>
>>   <ex:editor rdf:nodeID="abc">
>>     <ex:homePage rdf:resource="http://purl.org/net/dajobe/"/>
>>   </ex:editor>
>></rdf:Description>
> 
> Not quite, you broke the node element / property element striping
> there so the innermost ex:homePage is a node element and doesn't take
> rdf:resource, does take an rdf:about (see I said it was confusing!).

Actually, it does take an rdf:resource, which is exactly my point. 
Here's what this is meant to encode:

<rdf:Description>
   <ex:editor>
     <rdf:Description rdf:nodeID="abc"
       <ex:homePage rdf:resource="http://purl.org/net/dajobe/"/>
     </rdf:Description>
   </ex:editor>
</rdf:Description>

Here, rdf:nodeID is serving the same function as rdf:about. In the above 
example, you noted that I can't put another property ex:homePage that 
describes the resource represented by rdf:nodeID="abc". That's because 
*that* occurrence of rdf:nodeID is talking about the node in the context 
of the object of ex:editor, not as the subject of ex:homePage.

As the object of ex:editor, the node ID should be represented by a 
reference (e.g. rdf:nodeIDRef="abc") analogous to rdf:reference. As the 
subject of ex:homePage it should be represented by rdf:nodeID analogous 
to rdf:about. If rdf:nodeIDRef can talk about a node in the context of 
both an object and a subject, then the first example above should be 
allowed, to mean the same thing as the second example above.

My point here is that rdf:about and rdf:reference are used in different 
situations in the syntax depending on whether the resource identifies is 
taking the role of subject or object of a triple. The same should go for 
rdf:nodeID/rdf:nodeIDRef.

> rdf:nodeID is not in the graph at all.

Right, but the node it represents is on the graph. That's what was meant.

> You really can change any RDF/XML with rdf:about and/or rdf:resource
> attributes to use rdf:nodeID and that is ok.

So, why don't we deprecate rdf:resource and allow rdf:about wherever we 
can have an rdf:resource? I really don't see the confusion for having 
both, though.

Garret
Received on Tuesday, 14 January 2003 14:44:17 GMT

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