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

From: Dave Reynolds <dave.e.reynolds@googlemail.com>
Date: Mon, 04 Jan 2010 08:28:49 +0000
Message-ID: <4B41A6C1.4050200@gmail.com>
To: Jiří Procházka <ojirio@gmail.com>
CC: Semantic Web <semantic-web@w3.org>
Jiří Procházka wrote:
> Sorry for resurrecting this old thread, but I just stumbled upon this:
> 
> "rdfs:Datatype is both an instance of and a subclass of rdfs:Class. Each
> instance of rdfs:Datatype is a subclass of rdfs:Literal."
> 
> "A typed literal is an instance of a datatype class."
> 
> citing http://www.w3.org/TR/rdf-schema/#ch_datatype
> 
> So I think this is valid:
> 
> _:x rdf:type xsd:date .
> _:x owl:sameAs "2008-01-01" .

Not as such, did you mean:

  _:x rdf:type xsd:date .
  _:x owl:sameAs "2008-01-01"^^xsd:date .

? Which would, I believe, be valid.

Dave

> 
> Quite confusing, but might be useful for RDF systems which treat
> literals as just one "type" (type from their point of view).
> 
> Shame there is no such thing for language tags, or is there?
> 
> Best,
> Jiri Prochazka
> 
> On 07/06/2009 07:43 PM, Jeremy Carroll wrote:
>> Pat Hayes wrote:
>>>>> p a rdf:Property ;
>>>>>  rdfs:domain rdfs:Literal ;
>>>>>  rdfs:range rdfs:Datatype .
>>>
>>> _:x p xsd:date .
>>> _:x :seenAsLiteral  "2008-01-01" .
>> I tend to write these examples as
>>
>> _:x p xsd:date .
>> _:x owl:sameAs  "2008-01-01" .
>>
>> Semantically that has a literal as the subject, and it works around the
>> legacy syntactic restriction
>>
>> Unfortunately the reasoning required to make this work means that simple
>> RDF systems may well not get it.
>>
>> Jeremy
>>
>>
>>
> 
Received on Monday, 4 January 2010 08:29:26 UTC

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