W3C home > Mailing lists > Public > www-rdf-interest@w3.org > October 2001

Re: RDFCore Update

From: Devon Smith <devon@taller.pscl.cwru.edu>
Date: Thu, 18 Oct 2001 16:46:11 -0400
To: Patrick.Stickler@nokia.com
Cc: www-rdf-interest@w3.org
Message-ID: <20011018164611.A498@taller.pscl.cwru.edu>
On Thu, Oct 18, 2001 at 10:46:49PM +0300, Patrick.Stickler@nokia.com wrote:
> 
> > From: "Brian McBride" <bwm@hplb.hpl.hp.com>
> > 
> > > One major area of focus for the WG at the moment is 
> > datatyping, e.g. using
> > XML
> > > schema datatypes in RDF.  Now would be a good time to let 
> > us have your
> > thoughts
> > > and ideas on this.
> > 
> > I think values should be anonymous nodes in RDF with property arcs
> > describing them in XML datatypes.
> > 
> > Seth Russell
> 
> Yes. That's one approach. But not necessarily the only or
> most optimal approach for all circumstances.
> 
> IMO it should also be possible to assign types to values in
> other ways, and there should be some official equivalence
> logic defined for these variant methods.
> 
> One would presume that all of the following three examples
> define precisely the same knowledge regarding data types:
> 
> --
> 
> <rdf:Description rdf:about="urn:foo:bar">
>   <abc:someProperty>
>     <rdf:Description>
>       <rdf:type rdf:resource="x:dataType"/>
>       <rdf:value>dataValue</rdf:value>
>     </rdf:Description>
>   </abc:someProperty>
> </rdf:Description>
> 
> --
> 
> <rdf:Description rdf:about="urn:foo:bar">
>   <abc:someProperty>dataValue</abc:someProperty>
> </rdf:Description>
> 
> <rdf:Description rdf:about="abc:someProperty">
>   <rdfs:range rdf:resource="x:dataType"/>
> </rdf:Description>

wouldn't this use of rdfs:range change it's semantics?
if it's used as a type specification mechanism, that would seem
to exclude it from being used as a type verification mechanism.
that is, if my parser reads in the fragment above, does it reject
it because 'dataValue' isn't of type x:dataType, or does it decide
that 'dataValue's type is x:dataType. i've understood rdfs:range to
mean the former. i guess it could be used for both, where the 
specification would apply to literals and verification would be used
with resources. that would exclude verification for any literal
values though. 

devon smith
Online Computer Library Center
smithde@oclc.org

> 
> --
> 
> <rdf:Description rdf:about="urn:foo:bar">
>   <abc:someProperty rdf:resource="x:dataType:dataValue"/>
> </rdf:Description>
> 
> --
> 
> There are valid reasons why each of these options should
> be allowed and ideally, these would have a consistent
> interpretation by RDF applications.
> 
> Regards,
> 
> Patrick
> 
> --
> Patrick Stickler                      Phone:  +358 3 356 0209
> Senior Research Scientist             Mobile: +358 50 483 9453
> Nokia Research Center                 Fax:    +358 7180 35409
> Visiokatu 1, 33720 Tampere, Finland   Email:  patrick.stickler@nokia.com
>  
Received on Thursday, 18 October 2001 16:41:14 GMT

This archive was generated by hypermail 2.2.0+W3C-0.50 : Monday, 7 December 2009 10:51:52 GMT