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Re: do bad datatype literals denote [was Re: Datatype test cases ...]

From: pat hayes <phayes@ai.uwf.edu>
Date: Wed, 20 Nov 2002 13:43:01 -0600
Message-Id: <p05111b0cba019555bf08@[10.0.100.86]>
To: Brian McBride <bwm@hplb.hpl.hp.com>
Cc: w3c-rdfcore-wg@w3.org

>At 10:42 20/11/2002 -0600, pat hayes wrote:
>
>[...]
>
>>Oh, I thought that lang tags simply couldn't be attached to 
>>datatyped literals other than rdf:XMLLiterals, so this would be a 
>>syntax error. That's what the graph syntax rules seem to say. Is 
>>that wrong??
>
>Well, I don't think its what they do say.  I think its what they 
>should say, but that is not what the WG agreed.

Hmmm. So an literal can have three components: a string, a dtype and 
a lang tag, even when the dtype isn't rdf:XMLLiteral??

I just want to get this very clear, as I want to have all the cases 
listed in the basic MT rules. Right now there are cases I am missing, 
apparently.

>
>[...]
>
>>It works but for a different reason. Perhaps I should spell this 
>>out more in the semantics doc.
>>
>>Making the denotation be something arbitrary in this case (ie not a 
>>literal value, but otherwise it could be anything) means that the 
>>ONLY entailment you can get is what you would get from basic graph 
>>interpretations, which is replacing the bad literal by a new bnode:
>
>Hmmm, are you saying that it does not entail the emtpy graph.  I 
>think I wasn't clear; I'm trying to clarify precisely the test case 
>proposed by jan, non-well-formed-literal-2, in
>
>   http://www.w3.org/2000/10/rdf-tests/rdfcore/datatypes/Manifest.rdf
>
>
>  The test case is (something like)
>
>   <a> <b> "Arggggggg"^^xsd:integer .
>
>does not entail the empty graph.
>
>I think the MT says it does, but I'm appealing to you for confirmation.

Yes, anything entails the empty graph, because the empty graph is 
always true. It also entails

<a> <b> _:x .

>
>[...]
>
>>5 (??) If all the above and you know from the datatype mavens that 
>>some properties are true on some datatype values, then you can 
>>conclude some more triples using those properties. (Jos' idea) ??
>>
>>Im not sure about the last one: do we want to go there?
>
>Please no.

Yes, I tend to agree at this stage. Still, it would have been fun.

Pat


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Received on Wednesday, 20 November 2002 14:43:07 EST

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