Need a few basic Classes in RDFS

Hello,

We're trying to design a RDF-based information retrieval system, and we
discover that we really need to define a few general-purpose Classes, as
possible values of RDFS:Range
The most obviously needed are (non exhaustive list!) :
	Numerals
	Integers
	PositiveIntegers
	URI
	MimeType

Of course we can perfectly define these Classes in our own schema, and
implement in our application the corresponding processes (validity checking
of declarations, automatic computation of value-ranges by transitive
closures, etc.)
I'm concerned by the interoperability problems that may rapidly emerge if
many developpers define their own schema with these basic classes locally
re-defined.
Some systems will process foo:Integers, others Bar:Integers, and how would
they recognise ++efficiently++ that when some declarations are imported
from system A to system B, foo:Integers is (hopefully!) strictly equivalent
to 
bar:Integers ?

The rdf and rdfs constructors are of course "wired" in our application, as
are our basic Classes. 
If these basic Classes were standardised in the future RDFS recommendation,
it would enable all developpers to "wire" them in their code, avoiding
possible mismatches and overhead (having to download some other schema,
serialize it, and process foo:Integers as if it was another object than
bar:Integers).

In fact, my understanding is that if many people define the +same+ objects
separately and in separate namespaces, it may kill all the potential
benefits of namespaces!

I feel that the relevant working-group should seriously consider the
standardization of a few basic classes, exactly as it has been done (and
perhaps for the same reasons) for the possible values of rdfs:necessityValue.

The idea that on the long-term, a more general "XML-schema" should solve
the issue does not answers to my concern.

Best regards
Alain Michard
INRIA

Received on Wednesday, 5 August 1998 04:51:41 UTC