Disjointness of value spaces

The RDFCore WG are putting the finishing touches to a proposal for using 
XML Schema Datatypes in RDF graphs.  We hope to have a WD to share with 
folks soon.

In doing this, the following question has arisen concerning the value 
spaces of the primitive datatypes.

Are the value spaces of the primitive datatypes disjoint, i.e. are there 
any cases where a value may be in more than value space.  A specific case 
to consider is:

   is http://example.org/ in both xsd:string and xsd:anyURI

noting that RFC 2396 states:

   [[An identifier is an object that can act as a reference to
          something that has identity.  In the case of URI, the object is
          a sequence of characters with a restricted syntax.]]

Put another way, can we assume that if we have two values, one from the 
value space of one primitive datatype, and the other from the value space 
of a different primitive datatype, then they must be different values.

To the best of my knowledge, the RDFCore WG has no preferred answer to this 
question.  We wish to know the answer to ensure that our specification 
accurately reflects XML Schema datatypes.

Brian McBride
RDFCore co-chair

Received on Thursday, 31 October 2002 09:41:13 UTC