Re: RDFa, Embedded RDFa and GRDDL

On Tue, 23 Jan 2007, Dan Connolly wrote:

>
>> In the case of Embedded RDF, while it allows us to embed some fragment of
>> RDF, it does not currently work in the example in the primer due to its
>> lack of ability to support XML Schema Data Types  and I refuse
>> to ship broken examples to Last Call. Perhaps it could be used in the
>> second section of the primer, although it would complicate the example.
>> If IanD does not get enough cycles free to respond to either adding
>> Embedded RDF data-types or changing the examples, we will have no choice
>> but to remove it from the primer and reference Embedded RDF in the
>> use-case document.
>
> Hmm... why do we need datatypes in the primer? I guess I'll have
> to take a closer look. But I agree that we need to get the primer
> to be internally consistent before last call.

In the current editor's draft of the primer [1], we use this FILTER 
statement to match dates:

FILTER ( ?start1 = ?start2 && ?stop1 = ?stop2 && ?url1 != ?url2 && 
?location1=?location2) .

The use of SPARQL inequality does not work unless datatypes are 
consistent. Therefore unless Embedded RDF supports data-types we should 
probably move the example currently in the primer to RDFa, and test to see 
if Fabien's XSLT supports use of XML Schema datatypes in RDFa.

>> Re RDFa, we have left  the spec open enough so that a GRDDL  result is
>> defined in terms of graphs, not RDF/XML, so a GRDDL result can be a RDFa document.
>
> That's not using GRDDL for RDFa; that's using RDFa as an RDF syntax.

However, without a RDFa-enabled parser, we cannot easily get graphs from 
RDFa into our test-harness, and so the results of an hGRDDL transformation
seem unable to be useful as proof that we can "bootstrap" RDFa.

Therefore the best we can do is to use Fabien's (thanks for the reminder!) 
RDFa->RDF/XML transform in the primer. I'll put approving this test-case 
into next week  agenda's when Fabien returns to our telecon as he is 
missing tomorrow's telecon, and then we should get an action to update the 
primer so it's internally consistent and the examples actually work.

>> 3) RDFa to have a stable syntax.
>
> Why? For GRDDL WG purposes, I don't see any major problems if
> RDFa syntax changes after our test suite is done. Our tests will
> become less valuable as real-world examples, but not any less
> valuable as GRDDL tests.

Because if we mention RDFa in the primer and the syntax changes we then 
have to revise the primer.

[1] http://www.w3.org/2001/sw/grddl-wg/doc29/primer.html


-- 
 				--harry

 	Harry Halpin
 	Informatics, University of Edinburgh
         http://www.ibiblio.org/hhalpin

Received on Wednesday, 24 January 2007 00:58:48 UTC