W3C home > Mailing lists > Public > w3c-rdfcore-wg@w3.org > October 2002

Re: N-Triples changes for datatype values, (possible) N3 alignment

From: Patrick Stickler <patrick.stickler@nokia.com>
Date: Thu, 24 Oct 2002 15:33:06 +0300
Message-ID: <006901c27b59$80d4ca10$279316ac@NOE.Nokia.com>
To: "ext Dave Beckett" <dave.beckett@bristol.ac.uk>
Cc: <w3c-rdfcore-wg@w3.org>



[Patrick Stickler, Nokia/Finland, (+358 40) 801 9690, patrick.stickler@nokia.com]


----- Original Message ----- 
From: "ext Dave Beckett" <dave.beckett@bristol.ac.uk>
To: "Patrick Stickler" <patrick.stickler@nokia.com>
Cc: <w3c-rdfcore-wg@w3.org>
Sent: 24 October, 2002 14:33
Subject: Re: N-Triples changes for datatype values, (possible) N3 alignment 


> >>>Patrick Stickler said:
> > 
> > > 
> > >    "10"^^<http://www.w3.org/2001/XMLSchema#int>
> > 
> > Do I understand correctly that N3 will be preserving the
> > unity of the above node and not treating the above as a 
> > short hand for
> > 
> >    [ <http://www.w3.org/2001/XMLSchema#int> "10" ]
> 
> That's right - it will not generate the above.

OK.

> > Does ^^ have any present definition in N3? I've only ever seen
> > the single ^ used.
> 
> No, it is new syntax for this purpose, which is why I discussed it
> with Dan Connolly.

Are there any plans for it to generate triples? (I would expect
not, and would hope there would be language somewhere to the
effect that it would be disallowed in some fashioin)

Also, I am very curious as to the need for any of the "extra" 
delimiting characters.

Is not 

    "10"en-US<http://www.w3.org/2001/XMLSchema#int>

sufficiently explicit for parsing? The string final " and
the URI initial < seem to be sufficient to unambiguously
mark the boundaries of the components. Why are @ and ^^ 
actually needed?

KISS would seem to call for their omission, which would 
further serve to prevent their being given special significance
by alternate serializations which would result in a typed
literal node to triples interpretation.

Entailments/rules are another issue entirely. I don't mind
someone saying

{
   "LLL"<ddd>
}
log:implies
{
   [ <ddd> "LLL" ]
}

but I want to see that typed literal node remain as a typed
literal node (if we're talking about RDF) even if someone
wants to infer other triples from it.

> Can you provide me a real non-XSD example, that I can add to the
> N-Triples test?

Here are some "based on" UAProf. I say "based on" because there
don't appear to be official URIs for these datatypes, since RDF
didn't provide as yet a datatyping solution for UAProf to use.
But based on the existing RDF schema and examples from Mark Butler
in http://lists.w3.org/Archives/Public/w3c-rdfcore-wg/2002Aug/0150.html,
I think these are acceptable since the names used are defined by
that schema, albeit in the comments rather than in the RDF. Graham?

 "10"^^<http://www.wapforum.org/profiles/UAPROF/ccppschema-20010430#Number>

 "foo"^^<http://www.wapforum.org/profiles/UAPROF/ccppschema-20010430#Literal>

 "Yes"^^<http://www.wapforum.org/profiles/UAPROF/ccppschema-20010430#Boolean>

 "200x100"^^<http://www.wapforum.org/profiles/UAPROF/ccppschema-20010430#Dimension>

The above datatypes are all supported by, and can be tested with the
code available at http://www-nrc.nokia.com/sw/datatypes.zip. Including
the ability to compare values of these datatypes with those of XML Schema,
where "true"^^xsd:boolean == "Yes"^^uap:Boolean, etc.

Patrick
Received on Thursday, 24 October 2002 08:33:11 EDT

This archive was generated by hypermail pre-2.1.9 : Wednesday, 3 September 2003 09:52:29 EDT