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Re: xsi:type test case

From: Graham Klyne <Graham.Klyne@MIMEsweeper.com>
Date: Tue, 06 Aug 2002 17:49:18 +0100
Message-Id: <5.1.0.14.2.20020806173957.03b70ec0@127.0.0.1>
To: "Jeremy Carroll" <jjc@hplb.hpl.hp.com>
Cc: <w3c-rdfcore-wg@w3.org>

At 05:38 PM 8/2/02 +0200, Jeremy Carroll wrote:

>Are the two documents descriptions of the same graph?
>
><rdf:RDF>
>   <rdf:Description>
>     <eg:prop xsi:type="xsd:decimal">2.0</eg:prop>
>   </rdf:Description>
></rdf:RDF>
>
>
>
><rdf:RDF>
>   <rdf:Description>
>     <eg:prop xsi:type="xsd:decimal">2.00</eg:prop>
>   </rdf:Description>
></rdf:RDF>
>
>I think I heard yes.

If the literal is intended to be a number, then I think yes.

But a possible issue then would be that RDF engines without knowledge of 
XML schema datatypes would get different answers from engines that do have 
such knowledge.  I don't know if that's a problem.


>Furthermore is this the same:
>
><rdf:RDF>
>   <rdf:Description>
>     <eg:prop xsi:type="xsd:int">2</eg:prop>
>   </rdf:Description>
></rdf:RDF>
>
>I suspect it is too?

Hmmm... I'd need to consult XML schema details for that.

And what about:

<rdf:RDF>
   <rdf:Description>
     <eg:prop xsi:type="xsd:float">2.0</eg:prop>
   </rdf:Description>
</rdf:RDF>

In this case I think the answer is no.  (For reasons mentioned in the 
message Dan cited recently -- 
http://lists.w3.org/Archives/Public/www-xml-schema-comments/2000JanMar/0130.html)

The question raised, I think, is does constructing the correct abstract 
graph depend on knowing about the datatypes?  If so, then I think 
extensibility has just been comprehensively denied.  (Which is not too 
surprising, if one considers the way programming languages typically 
distinguish syntactically between literal types -- the range of literal 
types is often prescribed by the language, though complex values may 
sometimes be constructed from them.)

#g


-------------------
Graham Klyne
<GK@NineByNine.org>
Received on Tuesday, 6 August 2002 13:37:40 EDT

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