Re: range, domain: Conjunctive AND disjunctive semantics both supportable; constraints should be identical

On Fri, 29 Sep 2000, Peter F. Patel-Schneider wrote:

> From: Jan Grant <Jan.Grant@bristol.ac.uk>
> Subject: range, domain: Conjunctive AND disjunctive semantics both           supportable; constraints should be identical
> Date: Fri, 29 Sep 2000 10:21:53 +0100 (BST)
> 
> > and loosely:
> > 
> > P has a range of (a member of the union of A and B)
> > 
> > 	A --[rdfs:subclassOf]-> anon:C
> > 	B --[rdfs:subclassOf]-> anon:C
> > 	P --[rdfs:range]-> anon:C
> > 
> > (give anon:C a real URI if you prefer).
> > 
> > Are there problems with this scheme?
> 
> Unfortunately, this does not restrict the range of P to the union of A and
> B but instead to some (unspecified) superset of the union.  

Yep, I acknowledge this; that's why I said it might be used for
validation (of some existing RDF against such a schema) but not for
inferencing (unless the application layer knows that the closed-world
assumption is a reasonable one).

jan

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jan grant, ILRT, University of Bristol. http://www.ilrt.bris.ac.uk/
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