Re: Primer XPackage examples [was Re: Review of RDF primer Revised Editor's Draft 21 July 2003]

On Fri, 01 Aug 2003 19:16:56 -0400
Frank Manola <fmanola@mitre.org> wrote:

> Dave (and for everyone's information)--
> 
> Regarding your comments below on the XPackage examples:
> 
> I reviewed the XPackage examples again (I *thought* I'd validated them, 
> and it turns out I had).  The complete example 37 (with all the 
> namespaces declared) is:
> 
> <?xml version="1.0"?>
> <xpackage:description
>             xmlns:xpackage="http://xpackage.org/namespaces/2003/xpackage#"
>             xmlns:rdf="http://www.w3.org/1999/02/22-rdf-syntax-ns#"
>             xmlns:rdfs="http://www.w3.org/2000/01/rdf-schema#"
>             xmlns:dc="http://purl.org/dc/elements/1.1/"
>             xmlns:mime="http://xpackage.org/namespaces/2003/mime#"
>             xmlns:x="http://xpackage.org/namespaces/2003/xml#"
>             xmlns:xlink="http://www.w3.org/1999/xlink">
>      <rdf:RDF>
> <!--doc.html-->
>          <rdf:Description rdf:about="urn:example:xhtmldocument-doc">
>            <rdfs:comment>The XHTML document.</rdfs:comment>
>            <xpackage:location xlink:href="doc.html"/>
>            <mime:contentType>application/xhtml+xml</mime:contentType>
>            <x:namespace rdf:resource="http://www.w3.org/1999/xhtml"/>
>            <x:style rdf:resource="urn:example:xhtmldocument-stylesheet"/>
>            <dc:creator>Garret Wilson</dc:creator>
>            <xpackage:manifest rdf:parseType="Collection">
>               <rdf:Description
>                       rdf:about="urn:example:xhtmldocument-stylesheet"/>
>               <rdf:Description
>                       rdf:about="urn:example:xhtmldocument-image"/>
>            </xpackage:manifest>
>          </rdf:Description>
> 
>      </rdf:RDF>
> </xpackage:description>
> 
> This validates in the W3C RDF validator.  In the generated triples, the 
> xpackage:location property has a blank node as its object, and the blank 
> node in turn has a http://www.w3.org/1999/xlinkhref property whose value 
> is the literal "doc.html".  Example 38 works the same way.  Does this 
> not square with your understanding of what's supposed to happen? 

It does.  What you describe in the first sentence is what I explained
in my comment.  The point is, the xlink:href is not special, and RDF/XML
has no special processing for it's value - which looks like a URI.
It might be misleading if people read it that way.  
  <xpackage:location xlink:href="doc.html"/>
makes 2 triples - which I think is only clear if you recognised that
abbreviation, or tried it out, such as by using a validator:
  _:a xpackage:location _:b .
  _:b xlink:href "doc.html" .

(I'm sad to see this abbreviation used, I would have liked to have killed it)

Dave

Received on Monday, 4 August 2003 05:47:10 UTC