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Re: owl:hasValue range?

From: Jeff Z. Pan <pan@cs.man.ac.uk>
Date: Fri, 21 May 2004 23:39:24 +0100
Message-ID: <00d901c43f84$89a0db70$6bc65882@cs.man.ac.uk>
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

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