RE: POWDER + GRDDL + RDF/XML

> -----Original Message-----
> From: public-grddl-wg-request@w3.org
> [mailto:public-grddl-wg-request@w3.org] On Behalf Of Jeremy Carroll
> Sent: Friday, January 25, 2008 2:05 PM
> To: david.booth@hp.com; public-grddl-wg@w3.org
> Cc: Phil Archer
> Subject: POWDER + GRDDL + RDF/XML
>
>
>
> David,
>
> I suspect it would be helpful to the POWDER WG if we could
> agree what we
> agree on, and what we disagree on. Here is a straw man:
>
> We agree:
> - the POWDER format should be heavily constrained, to allow easy
> processing of operational semantics by an XML app

Yes, though I would shorten that to " . . . to allow easy process by an XML app", i.e., not mention "operational semantics".

> - the POWDER format should not be unconstrained RDF/XML

Yes.  This follows from the previous one.

> - the full formal meaning of a POWDER document should most easily be
> accessed by use of GRDDL

Yes.

> - to permit adding arbitrary metadata, some part of a POWDER document
> should be defined in terms of
> http://www.w3.org/TR/rdf-syntax-grammar/#start
> (most probably one of nodeElement or nodeElementList)

Yes.

> - the meaning of any RDF/XML included in the POWDER document should be
> consistent with the GRDDL result.

I think so.  I haven't had time to figure out how POWDER causes sets of assertions to be applied to a particular set of resources, but assuming it is monotonic to immediately assert the triples from the embedded RDF/XML, then yes.

>
> We disagree:
> - whether a powder document as a whole should match the nodeElement
> construction of RDF/XML)
> - whether the powder document should be served as RDF/XML or as XML.

I'll address these in a separate message, to avoid cluttering this one.

>
>
> We have not yet finish understanding the differences in opinion
> concerning entailment relationships.

It sounds like the GRDDL processing is, in effect, implementing the semantic extensions
http://www.w3.org/TR/rdf-mt/#MonSemExt
implied by the powder spec.  If so, it sounds like the GRDDL results, in effect, would all be entailments of the directly embedded RDF.  Assuming they are monotonic (as required by the RDF semantics) that sounds good to me.  I like that approach.

>
> In my view the agreements above are much more extensive and important
> than the disagreements.

Absolutely.


David Booth, Ph.D.
HP Software
+1 617 629 8881 office  |  dbooth@hp.com
http://www.hp.com/go/software

Opinions expressed herein are those of the author and do not represent the official views of HP unless explicitly stated otherwise.

Received on Monday, 28 January 2008 13:58:22 UTC