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Re: Some questions on properties

From: Stefan Decker <stefan@db.stanford.edu>
Date: Wed, 26 Apr 2000 17:31:00 -0700
Message-Id: <4.2.0.58.20000426171139.00daa5a0@db.stanford.edu>
To: Jan Wielemaker <jan@swi.psy.uva.nl>, www-rdf-interest@w3.org



>Two new questions.  First looks like a bug in the 02/22 specs:
>
>================================================================
><?xml version="1.0"?>
>
><!-- Example from REC-rdf-syntax, demonstrating abbrevation -->
>
><rdf:RDF xmlns:rdf="http://www.w3.org/1999/02/22-rdf-syntax-ns#"
>          xmlns:s="http://description.org/schema/"
>          xmlns:v="http://description.org/view/">
>   <rdf:Description about="http://www.w3.org/Home/Lassila">
>     <s:Creator>
>       <!-- REC-rdf-syntax just says `about' -->
>(*)   <s:Person rdf:about="http://www.w3.org/staffId/85740">
>         <v:Name>Ora Lassila</v:Name>
>         <v:Email>lassila@w3.org</v:Email>
>       </s:Person>
>     </s:Creator>
>   </rdf:Description>
></rdf:RDF>
>================================================================
>
>In the (*) line, it says simply `about', but if I understand things
>correctly this brings `about' in the `s' names space, resulting in
>a quite different interpretation.  Right?

"about" and "ID" are somewhat not affected by namespaces, when used as 
defined in the
RDF-Specification.

>Second is again on the protertyElt production [6.12].
>
>What is the difference between
>
>   <rdf:Description ID="foo">
>     <a1 ID="bar">
>        <rdf:Description>
>           <name>Hello World</name>
>        </rdf:Description>
>     </a1>
>   </rdf:Description>
>
>and
>
>   <rdf:Description ID="foo">
>     <a1>
>        <rdf:Description ID="bar">
>           <name>Hello World</name>
>        </rdf:Description>
>     </a1>
>   </rdf:Description>
>
>I have the impression they should be the same and specifying both ID's
>inconsistent is an error.  Right?

The first definition gives the ID "bar" to the statement {foo,a1,genid1}
the second definition gives an ID the second resource and leads to the 
triple {foo,a1,bar}.

Best,
         Stefan



>         Regards --- Jan
Received on Wednesday, 26 April 2000 20:30:41 GMT

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