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Re: RDFa review ... too late, but maybe still helpful for the group

From: Axel Polleres <axel.polleres@deri.org>
Date: Wed, 08 Oct 2008 09:14:40 +0100
Message-ID: <48EC6BF0.80004@deri.org>
To: Shane McCarron <shane@aptest.com>
CC: Ben Adida <ben@adida.net>, public-rdf-in-xhtml-tf@w3.org, "Passant, Alexandre" <Alexandre.Passant@deri.org>, Benjamin Heitmann <benjamin.heitmann@deri.org>

just correcting alexandre's reply address in the (cc:)
was misspelled before, apologies.


Shane McCarron wrote:
> My comments are in line.  Mark, there is an item in here that we really 
> need your input to react to.  I know you are buried, but 5 minutes would 
> be really helpful.
> Ben Adida wrote:
>> Hey folks,
>> Thanks for your review!
>> A few comments below in response to your questions. Mark, Shane, and
>> Steven might chime in to enhance the response :)
>> We'll do our best to incorporate as much as we can here, though we are
>> on a tight deadline to publish. Comments below.
>>> The inconsistent specification of the CURIE syntax is the main critical
>>> question we have, which occurs in more than one section.  The main
>>> question is whether a CURIE must contain a colon, or need not.  The
>>> formal syntax definition in section 7 says
>>>> curie       :=   [ [ prefix ] ':' ] reference
>>> but the definition of the XML Schema datatype in appendix B.1 does not
>>> reflect the fact that the colon can be missing:
>>>> <xs:simpleType name="CURIE">
>>>>     <xs:restriction base="xs:string">
>>>>       <xs:pattern value="[\i-[:]][\c-[:]]*:.+" />
>>>>     </xs:restriction>
>>>> </xs:simpleType>
>> Good point about the inconsistency, we'll be clearer about that. A valid
>> CURIE need not have a colon, but CURIEs in @rel/@rev *do* need a colon,
>> and that is indeed an intended design tidbit: we don't want rel="foobar"
>> to mean something by default, but we *do* want rel="next" to mean what
>> it has always meant.
> This was actually already corrected.  The XSD now matches the BNF.  And 
> yes, this means that rel="foobar" is syntactically valid were the 
> definition of @rel to use that datatype.  It will not when we have an 
> XML Schema implementation of RDFa+XHTML - @rel and @rev will have a 
> custom datatype that contains the reserved values.
>>>> @rel and @rev support both XHTML link types and CURIEs
>>> If XHTML link types like "next" turn out to be CURIEs, this will have 
>>> to be
>>> rephrased.
>> We could say "prefixed CURIEs," but I'll let Mark and Shane explain 
>> further.
> "next" is syntactically legal as a CURIE.  However, section 7 says "the 
> *mapping to use when there is no prefix* is not defined, which 
> effectively prohibits the use of CURIEs that do not contain a colon;"  
> This means that within the context of RDFa+XHTML "next" is NOT permitted.
>>>  So if redefining the default namespace does not have any impact on 
>>> the URI prefix
>>> mapping that is relevant for CURIEs, this should be explained by a
>>> dedicated example.
>> We might make it a dedicated test case, although I could have sworn we
>> had one (but I can't find it yet). I don't think we'll change language
>> at this point, as this has not been an issue so far. Mark, Shane, feel
>> free to correct me.
> Every test case defines a default namespace that never has an effect on 
> the generated triples.
>>> == 5.5 Sequence ==
>>>> 9. . the actual literal value is obtained as follows:
>>>> * as a [typed literal] if:
>>>>   * @datatype is present, and does not have an empty value
>>> Note that this condition covers the case @datatype=rdf:XMLLiteral, so it
>>> should be changed to: "does not have an empty value, nor the value
>>> XMLLiteral"
>> I think technically that's covered by the other condition matching, but
>> you're right that this would help clarify things and be more precise.
> This is probably correct, but I am reluctant to make this change without 
> Mark's agreement and explicit wording.
>>> ==== Using @src ====
>>>> The complete mark-up yields three triples:
>>>> ...
>>>> <photo1.jpg> xh:license <http://...> .
>>> xhv is the correct prefix.
>> Good catch!
> Fixed.  Thanks!

Dr. Axel Polleres, Digital Enterprise Research Institute (DERI)
email: axel.polleres@deri.org  url: http://www.polleres.net/

Everything is possible:
rdfs:subClassOf rdfs:subPropertyOf rdfs:Resource.
rdfs:subClassOf rdfs:subPropertyOf rdfs:subPropertyOf.
rdf:type rdfs:subPropertyOf rdfs:subClassOf.
rdfs:subClassOf rdf:type owl:SymmetricProperty.
Received on Wednesday, 8 October 2008 08:18:34 UTC

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