RE: [Fwd: XML Schema 1.1 Requirements]

> -----Original Message-----
> From: ext Jeremy Carroll [mailto:jjc@hplb.hpl.hp.com]
> Sent: 22 January, 2003 21:27
> To: RDF Core
> Subject: [Fwd: XML Schema 1.1 Requirements]
> 
> 
> 
> (first sent to webont just as valid for RDFCore)
> 
> I have made two comments [2],[3] on this new WD [1] that the 
> WG may wish to
> endorse, or follow up on.
>
> The relevant text is:
> [[
> 3.1.2 Desiderata
> 3.1.2.2 Systematic treatment of fundamental facets (RQ-24)
> Make the treatment of fundamental facets more systematic. 

Are XML Schema datatyping facets meant here? If so, then
this is outside the scope of RDF datatyping. RDF datatyping
does not provide mechanisms for defining datatypes, only
for denoting datatypes and associating lexical forms with
datatypes to unambiguously denote a datatype value. How
a given datatype is defined, e.g. whether it is with XML
Schema or some other framework, is irrelevant to RDF.

> Define canonical
> forms for all types,

NO. Definitely not. If a datatype defines canonical forms, fine,
but RDF Datatyping does not require them. They are insignificant
to the the semantics and therefore such a requirement would not
be justified and would preclude the use of datatypes with RDF
which do not define canonical lexical forms.

> and specify the rules for generating the 
> canonical
> form, given a value. 

This is a datatype specific function completely outside the scope
of RDF datatyping and should not be addressed in the RDF specs.

> Clarify the status of anySimpleType and 
> define its
> value space (if any). 

RDF does not say anything about any particular datatype. This
is for the XML Schema WG to define, and/or to be addressed in
a separate Note addressing XML Schema datatyping issues in RDF.

I would expect, though, that the class extension of xsd:anySimpleType
would be equivalent to the membership of rdfs:Literal.

> Clarify the assignment of types to nodes in the
> absence of relevant schema components. 

Default types? Other than rdf:Resource? I don't understand this
one.

> Distinguish our 
> identity relation
> from the mathematical relation of quantitative equality.

V unir ab pyhr jung guvf zrnaf, ohg BX ol zr ;-)

> ]]
> 
> and
> 
> [[
> 2.5.1 Desiderata
> 2.5.1.1 First class objects (RQ-23)
> Define an algorithm for generating a URI for any construct in 
> a schema (or,
> possibly, in a schema document), thus making schema 
> constructs first-class
> objects in the Web. Minimally the algorithm should cover 
> element( type)s,
> attributes, simple types, complex types, and notations. 
> Optionally it may
> also cover other constructs such as named groups and items in 
> enumerations
> of legal values.
> ]]

Ummm, XPointer?


Patrick

--
Patrick Stickler, Nokia/Finland, (+358 40) 801 9690, patrick.stickler@nokia.com

Received on Thursday, 23 January 2003 04:51:37 UTC