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Re: A brief primer on Qnames and URIs

From: Bijan Parsia <bparsia@cs.man.ac.uk>
Date: Thu, 15 Nov 2007 11:25:14 +0000
Message-Id: <501ADDA8-71DD-4C10-AD59-BD5418BCF296@cs.man.ac.uk>
Cc: public-owl-wg@w3.org
To: "Peter F. Patel-Schneider" <pfps@research.bell-labs.com>

On 15 Nov 2007, at 10:45, Peter F. Patel-Schneider wrote:

> Summary:  There are approved URIs for the XSD facets.

Ok, nice. Thanks for verifying that.

> Result:  I think that thus we can use the XSD names for the XSD facets
> 	 in OWL 1.1.

Welllllll.

[snip]
> Note, however, that the URIs for the datatypes are *not* the
> concatenation of their namespace http://www.w3.org/2001/XMLSchema and
> their local name.  For example the URI for integer is
> http://www.w3.org/2001/XMLSchema#integer, not
> http://www.w3.org/2001/XMLSchemainteger.  One would thus expect  
> that in
> an OWL or RDF document that the namespace for prefix xsd would be
> http://www.w3.org/2001/XMLSchema# and not the XML Schema namespace.
[snip]

Ye-ouch. So if we used qnames that could turn into the right uris, we  
wouldn't be reusing their qnames, in fact, we wouldn't be using  
universal names *in their namespace*, just one very similar that they  
probably still own.

My head hurts :(

So, at the least, we still need, for XML Syntaxes, to confirm that  
for xmlns:xsd="http://www.w3.org/2001/XMLSchema#" that things like

	<xsd:minInclusive....

or
	<... xsd:minInclusive="...

are cool with them. I would hope that it is!

OTOH, if we adopt their syntax for inline derived types, then we need  
*two* xsd declarations (the inner one shadowing the outer one)?!?!

I have to say that I would be willing to support a more user rational  
scheme over the objections (if any) of the XML Schema working group.  
To wit:
	We need to have resolvable URIs for user defined datatypes in XML  
Schema documents. If they punt, we should take over.
	We need sensible names for facet elements and URIs. If they  
disagree, we should take our case upwards.
	We need reasonable syntax for inline datatypes. I'm open that that  
would be fragments of XML Schema, but given the trickinesses of XML  
Literals in RDF/XML, I'm also open to something like the current design.

I've no evidence at the moment that the current XML Schema WG  
wouldn't be friendly and helpful on this points, but I strongly  
disagree with Jeremy's expressed opinion in the telecon that "If the  
XML Schema WG doesn't solve this, then it remains unsolved". *If*  
they are recalcitrant, we should still solve our problems.

Cheers,
Bijan.

P.S. Here's some ranting about this from an XMLy person:
	http://www.jenitennison.com/blog/node/49
Received on Thursday, 15 November 2007 11:23:43 GMT

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