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RE: incomplete datatyping (was: Re: datatypes and MT)

From: <Patrick.Stickler@nokia.com>
Date: Tue, 6 Nov 2001 12:35:23 +0200
Message-ID: <2BF0AD29BC31FE46B7887732114404316216D5@trebe003.NOE.Nokia.com>
To: melnik@db.stanford.edu, phayes@ai.uwf.edu
Cc: w3c-rdfcore-wg@w3.org
> > (BTW, I agree that this simple idea has its merits; but I think that
> > if we are going to insist that literals *must* be explicitly
> > datatyped, then we should impose this as an explicit syntactic
> > constraint in the very syntax of the language.)

This follows from the nagging feeling I've been having that
"typed" literals are not really "literals" in the strictest
sense.

> In principle, I agree. However, if we stick a single type to each
> literal we won't be able to deal with the cases where 
> multiple literals
> are required to determine the data value unambiguously
> 
> _x rdf:type ComplexNumber
> _x realDecimal "1.0"
> _x imaginaryDecimal "2.0"
> 
> as indicated in
> http://lists.w3.org/Archives/Public/w3c-rdfcore-wg/2001Nov/0103.html

I didn't catch this the first time I looked at this example,
but it seems to me that what we really have here is:

  _x rdf:type ComplexNumber
  _x realComponent [ rdf:value "1.0"; rdf:type xsd:decimal ]
  _x imaginaryComponent [ rdf:value "2.0"; rdf:type xsd:decimal ]

or using URV's

  _x rdf:type ComplexNumber
  _x realComponent <xsd:decimal:1.0>
  _x imaginaryComponent <xsd:decimal:2.0>

Thus we have a true complex value, which itself has two properties
each of which have a data typed literal value. Thus, in fact, this 
example doesn't contradict my earlier assertion for which this was 
offered as an exception.

Cheers,

Patrick
 
Received on Tuesday, 6 November 2001 05:35:51 EST

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