- From: Jeff Z. Pan <pan@cs.man.ac.uk>
- Date: Fri, 21 May 2004 23:39:24 +0100
- To: "Dan Brickley" <danbri@w3.org>, <www-rdf-logic@w3.org>
On May 18, 2004 12:41 AM, Dan Brickley wrote: > > I'm trying to understand how to use 'hasValue' when the values > I have in mind are literals. > > http://www.w3.org/TR/2004/REC-owl-ref-20040210/#ValueRestriction > suggests this is feasible. Yes, it is. > http://www.w3.org/2002/07/owl says: I cannot access this URL :-( > <rdf:Property rdf:ID="hasValue"> > <rdfs:label>hasValue</rdfs:label> > <rdfs:domain rdf:resource="#Restriction"/> > </rdf:Property> > I'm left puzzled, I guess because I thought OWL DL generally frowned on > properties which could point either to a resource or a literal. Maybe > built-in properties are excused from this? The OWL DL direct semantics covers only the lowest two layers, but not the built-in (meta) properties like owl:hasValue. For instances of owl:Property, they should be either instances of owl:ObjectProperty or instances of owl:DatatypeProperty, but not both. > Are both the following ok?: > > <owl:Restriction> > <owl:onProperty rdf:resource="#hasParent" /> > <owl:hasValue rdf:resource="#Clinton" /> > </owl:Restriction> Fine, Clinton is an individual and hasParent is an object property. > <owl:Restriction> > <owl:onProperty rdf:resource="#hasParentName" /> > <owl:hasValue>Bill Clinton</owl:hasValue> > </owl:Restriction> Fine too, as "Bill Clinton" is a plain literal (as you didn't specify which datatype you want to use) and hasParentName is a datatype property. Jeff -- Jeff Z. Pan ( http://DL-Web.man.ac.uk/ ) Computer Science Dept., The University of Manchester > thanks for any advice, > > Dan > >
Received on Friday, 21 May 2004 18:32:27 UTC