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Dataypes, literals, syntax

From: Jonathan Borden <jonathan@openhealth.org>
Date: Fri, 19 Jul 2002 08:56:02 -0400
Message-ID: <049d01c22f23$a3ca9a40$0a2e249b@nemc.org>
To: <www-rdf-logic@w3.org>
Cc: <www-rdf-comments@w3.org>

I just noticed:
http://lists.w3.org/Archives/Public/w3c-rdfcore-wg/2002Jul/0121.html

It got me thinking about literal datatypes (the above considers XML
datatypes).

Why not:

<rdf:Description rdf:about="foo://bar">
    <ex:property xsi:type="xsd:integer">10</ex:property>
</rdf:Description>

being defined to parse to:

<foo://bar> ex:property xsd:integer"10" .

wouldn't this solve much of the datatypes debate -- it would _syntactically_
distinguish typed literals, as Drew McDermott correctly points out is the
way to go, and would avoid issues related to nonmonotonicity related to
interpreting a triple based on a schema that may or may not be present.

such a facility is compatible with XML Schema. This is how an XML Schema
compatible application -- xsi: stands for XML Schema Instance -- would
interpret explicit datatyping info for an XML document.

Suppose that RDF were defined 'on top of' the _post schema validation_
infoset (PSVI) or alternately a _type adorned infoset_ (TAI), rather than
the plain XML infoset. In that case, datatypes would be explicitly provided
to RDF applications.

Otherwise RDF is not really using XML Schema _datatypes_ which really means
that the PSVI/TAI is being used as the input for an application that defines
semantics, rather in the absense of the PSVI/TAI -- i.e. the current
situation -- RDF is merely trying to use the XML Schema _datatype qnames_
which for which I don't see a clear consensus on how to proceed.

Jonathan
Received on Friday, 19 July 2002 09:01:54 GMT

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