Re: Explicit RDF property for "literal has datatype D"?

On Jul 6, 2009, at 9:53 AM, Toby A Inkster wrote:

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> On 6 Jul 2009, at 14:34, Christoph LANGE wrote:
>
>> p a rdf:Property ;
>>  rdfs:domain rdfs:Literal ;
>>  rdfs:range rdfs:Datatype .
>
>
> In terms of RDF, this can't be done. Well, the property could be  
> defined using RDFS, but it could never legally be used. The  
> definition would imply that "p" is used like so:
>
> 	"2008-01-01" p xsd:date .

rdfs:Literal is the class of literal VALUES, and bnodes and URIs can  
denote literal values. So you could use a bnode:

_:x p xsd:date .
_:x :seenAsLiteral  "2008-01-01" .

(I made up the second property, but you get the idea.)
OR, you could just ignore this damn silly syntactic restriction and  
put the literal in the subject, like many RDF systems now do.

Pat Hayes

>
> However, RDF doesn't allow a literal to be used as the subject of a  
> triple. Hence there is no property defined like the "p" you  
> describe. There are supersets of RDF (such as Notation 3) which  
> relax this restriction and would allow a property "p" like you  
> describe to be used.
>
> - --
> Toby A Inkster
> <mailto:mail@tobyinkster.co.uk>
> <http://tobyinkster.co.uk>
>
>
>
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Received on Monday, 6 July 2009 17:06:24 UTC