Re: Can XPointers be used as a name (was Re: RDDL for names ?(was Re:XMLSchema built-in data typenamespaceURI.))

[Eric van der Vlist <vdv@dyomedea.com>]

Jonathan Borden wrote:
> 
> Eric van der Vlist wrote:
> 
> Jonathan Borden wrote:
> >>
> >> An XPointer can be used as either a name or an address depending on the
> >> form. The raw name form is a name, the child sequence form is an address
> and
> >> the full form may combine characteristics of both. e.g.
> 
> >I am not contesting the fact that, generally speaking, a XPointer can be
> >used as a name, but the fact that I don't want to assign to my user
> >defined datatypes a name that depends on the location of my schema file
> >and thus that in this case a XPointer is not convenient.
> 
> This is where RDDL and/or Entity Catalogs come in.

Is RDDL competing with W3C XML Schema for intrusiveness :=)) ???

> Firstly RDDL being bound to the namespace URI, allows the schema file(s) to
> be located wherever.
> 
> Catalogs with proper resolution software can redirect namespace URIs to
> local or otherwise located RDDL documents.
> 
> >> <xsd:simpleType name="unsignedInt" id="unsignedInt">..
> >>
> >> http://www.w3.org/2000/10/XMLSchema#unsignedInt  is a perfectly good name
> >> (IMHO)
> >>
> >> .../xsd:simpleType[@name='unsignedInt'] is also an fine name (IMHO)
> 
> >Yes I have no problem with these ones, but I consider
> >
> >file:yourSchema.xsd#myUnsignedInt
> >
> >or even
> >
> >http://example.org/yourSchema.xsd#myUnsignedInt
> >
> >as bad names since they depend on the actual physical location of the
> >schema file.
> 
> This depends purely on your choice of a namespace URI. The issue at hand is
> that XML Schema types depend on QNames which of course are namespace
> qualified, and the crux of my argument is that a QName is shorthand for a
> URI. Of course if you pick a poor QName you will get an equally poor URI.

The URI may be a good schema location for my processing needs and a bad
choice as a base name for my datatypes.

The prefix is a shorthand for the namespace URI that is, in principle,
independent of the schema location.

This is a powerful feature of W3C XML Schema that would be lost if the
namespace URI had to match the schema location.

> The bottom line is that if you generally expect namespace URIs to resolve to
> something, as I do, that you ought equally expect QNames in this namespace
> to resolve to something -- and in particular something that is 'contained'
> in this namespace. 

I don't expect namespace URIs to resolve to something (at least, I don't
expect them to consistently resolve to a single document type).

> Since a namespace name is a URI, logically a QName ought
> to be considered contained in the hierarchy of this URI.

Yes, but again the prefix is a shorthand to the target namespace URI,
not to the schema location.

What would be wrong with my proposal to let people choose a complete
"name" (URI) for identifying their types ?

Those who would like it could use a scheme based on the schema location,
other could use the namespace URI if it's different from the schema
location and other could use whatever they like.

To me, it's just adding more flexibility without adding any complexity.

Eric
 
> -Jonathan

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Eric van der Vlist       Dyomedea                    http://dyomedea.com
http://xmlfr.org         http://4xt.org              http://ducotede.com
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