Re: IRI vs. URI Reference in RDFa

On 20 May 2011, at 05:53, Pat Hayes wrote:

> 
> On May 19, 2011, at 1:09 AM, Ivan Herman wrote:
> 
>> For the records, this is related to ISSUE-8[1]. Note also the advice I got from Felix Sasaki, former member of the Internationalization Activity in the W3C Team[2], which essentially advices to keep the IDN and its punycode equivalent as separate URIs as far as RDF is concerned.
> 
> I agree with this.
> 
> Pat 

+1


> 
> 
>> This seems to be in line with the proposal Manu. Maybe this is the opportunity for the RDF WG to officially close ISSUE-8.
>> 
>> Ivan
>> 
>> 
>> [1] http://www.w3.org/2011/rdf-wg/track/issues/8
>> [2] http://www.w3.org/mid/482F7435-3DD8-4FBB-A568-0D8937B2ED94%2540w3.org
>> 
>> On May 19, 2011, at 07:33 , Manu Sporny wrote:
>> 
>>> BCC-cross-posted to: SWCG, RDFa WG
>>> 
>>> There is an RDF/RDF Web Apps/RDFa coordination issue that the RDF Web
>>> Apps group needs to have resolved in order to take RDFa Core 1.1 and
>>> XHTML+RDFa 1.1 into Candidate Recommendation. We are requesting input
>>> from RDF WG and coordination help from SW CG
>>> 
>>> The basic question is what should an RDFa processor do when it comes
>>> across a value in an HTML document that looks like this:
>>> 
>>> <a rel="foaf:homepage"
>>> href="http://www.schweizer-küche.de/">Schweizer Küche</a>
>>> 
>>> The issue is being tracked here (raised by Mischa):
>>> 
>>> http://www.w3.org/2010/02/rdfa/track/issues/87
>>> 
>>> We had a very long conversation about it on the telecon last week:
>>> 
>>> http://www.w3.org/2010/02/rdfa/meetings/2011-05-12#ISSUE__2d_87__3a__IRI_vs__2e__URI_References
>>> 
>>> So the question is whether or not the markup above should generate this:
>>> 
>>> <> foaf:homepage <http://www.schweizer-küche.de/> .
>>> 
>>> or should generate this:
>>> 
>>> <> foaf:homepage <http://www.xn--schweizer-kche-qsb.de/> .
>>> 
>>> There were good arguments both ways, but I believe that the RDFa WG
>>> settled on the RDFa processor not modifying the URL value when
>>> generating the triples for two reasons:
>>> 
>>> 1) Punycoding URLs could change the meaning of the triple such that
>>> matching rules written by the author would no longer match.
>>> 2) Punycoding URLs are culturally imperialistic - most of the world's
>>> primary languages cannot be expressed in ASCII, we shouldn't
>>> force punycoding on all languages "other than English".
>>> 3) Modifying URLs away from the authors intent, or away from well-known
>>> transforms like relative-IRI to absolute-IRIs or normalized
>>> IRIs, is bad. We shouldn't attempt to guess what the author meant.
>>> 4) IDN is a hack and should be dragged into the street and shot
>>> (ok, so this is just my opinion :P)
>>> 
>>> So the general assertion is that RDFa Processors should only perform the
>>> following transformation on IRIs:
>>> 
>>> 1. Relative to Absolute IRI transformation.
>>> 
>>> That is, they shouldn't punycode and they shouldn't attempt to do any
>>> other processing on the IRI output by the processor. In other words,
>>> RDFa Processors shouldn't second-guess the document author. Thoughts?
>>> 
>>> -- manu
>>> 
>>> PS: This also, tangentially, re-opens the can of worms on equivalence
>>> testing for IRIs in RDF. Is http://example.com/ros&#xE9 the same as
>>> HTTP://example.com/ros%C3%A9 for equivalence testing in RDF?
>>> 
>>> -- 
>>> Manu Sporny (skype: msporny, twitter: manusporny)
>>> President/CEO - Digital Bazaar, Inc.
>>> blog: PaySwarm Developer Tools and Demo Released
>>> http://digitalbazaar.com/2011/05/05/payswarm-sandbox/
>>> 
>>> 
>> 
>> 
>> ----
>> Ivan Herman, W3C Semantic Web Activity Lead
>> Home: http://www.w3.org/People/Ivan/
>> mobile: +31-641044153
>> PGP Key: http://www.ivan-herman.net/pgpkey.html
>> FOAF: http://www.ivan-herman.net/foaf.rdf
>> 
>> 
>> 
>> 
>> 
>> 
>> 
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