On Fri, 7 Jan 2005 17:57:35 -0800, Roy T. Fielding <[EMAIL PROTECTED]> wrote:

> And it also says
> 
>   7 Sharp-eyed readers...

I was only providing an example for demonstration purposes. Broad brush strokes.

> > _:entry prism:embargoDate "2005-02-15" .
> >
> > The embargoDate is unambiguously a property of the entry. In the RSS
> > 1.0 case this is defined in the RDF model.
> 
> No, it isn't, as is clear from the PRISM specification itself.  XML
> does have a built-in containment relation, which is the essence of a
> mark-up language.  RDF/XML does extra work to override that containment
> relation for the sake of externally-defined metadata.  What you ascribe
> to RDF's inherent characteristics is, in fact, the opposite -- it is
> XML's native characteristics that are escaped by RDF/XML.

Perhaps I wasn't clear enough. XML has containment. Individual
specifications may assign it semantics. RDF/XML assigns it semantics
corresponding to the RDF model. Without either the individual
specification's definition, or a generalised interpretation like
RDF/XML's all you have is syntax featuring containment.

> Poorly targeted RDF mark-up will be just as vulnerable to
> misinterpretation
> as poorly designed XML mark-up, whereas properly designed XML mark-up is
> syntactically bound through containment to the resource it refers.
> E.g.,
> 
>     <entry other:embargoDate="20050202">stuff to be embargoed</entry>
> 
> XML does have a natural containment relationship that is only violated
> by specific types of languages that do not actually perform mark-up,
> namely RDF and its siblings.  

But XML containment can only express tree structures. To express graph
structures, the containment must somehow be violated. RDF is a graph.

(RDF/XML could probably have made a lot better use of XML's structure,
but it's a bit late in the day now).

While I don't see any reason not to make
> XML's mark-up relations explicit in the specification, 

That pleases me. That's all I'm hoping for.

I do hope that
> folks
> understand that the relationship should be obvious to anyone who does
> not
> work in a language that is as perversely non-mark-up as RDF/XML.

Well there you have it - it is possible to design XML languages that
are perverse. So we can't rely on everyone following the 'obvious'
relationship pattern. Making it explicit should help prevent
misinterpretation.

Cheers,
Danny.

-- 

http://dannyayers.com

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