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

From: Dave Beckett <dave.beckett@bristol.ac.uk>
Date: Wed, 20 Nov 2002 16:17:02 +0000
To: Brian McBride <bwm@hplb.hpl.hp.com>
cc: Jan Grant <Jan.Grant@bristol.ac.uk>, pat hayes <phayes@ai.uwf.edu>, Jeremy Carroll <jjc@hplb.hpl.hp.com>, RDFCore Working Group <w3c-rdfcore-wg@w3.org>
Message-ID: <13849.1037809022@hoth.ilrt.bris.ac.uk>

>>>Brian McBride said:
> At 14:49 20/11/2002 +0000, Jan Grant wrote:
> [...]
> > > We know that:
> > >
> > >   <a> <b> "foo"@@en#<datatype> .
> > >   <c> <d> "foo"@@fr#<datatype> .
> > >
> > > entails
> > >
> > >   <a> <b> _:l .
> > >   <c> <d> _:l .
> > >
> > > for all datatypes except rdf:XMLLiteral.
> >
> >It does? Doh.
> 
> I think so, but don't take my word for it.  Jeremy?
> 
> >I still think that's broken; but I'll fix the test case.
> >Basically these cases outline the various issues - I'll correct them as
> >appropriate.
> 
> Nah - see below - you got it right unless we know that datatype is not 
> rdf:XMLLiteral.  We know its not called that, but unless we make a unique 
> name assumption, we don't know that its not another name for the same thing.

I also think it is broken - hard to implement in a efficient fashion.
(And the N-Triples syntax above is wrong; ^^ not #)

Typed literals should be opaque nodes with identity, like URI-refs.
Looking at parts of them for RDF interpretations is wrong.  This
"ignoring the language in datatype interpretation except for
rdf:XMLLiteral" is seeming increasingly stupid.

If it said:
  [[
     <a> <b> XXX .
     <c> <d> XXX .

   where XXX is any legal syntax for typed literal object node

   entails

     <a> <b> _:l .
     <c> <d> _:l .
  ]]

Then it would make more sense to me.

<snip/>

Dave
Received on Wednesday, 20 November 2002 11:19:04 EST

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