RDF in XHTML 1.0 Task Force -- 08 Jan 2009

RDFa NS URL

<ShaneM> we do not use that namespac

<ShaneM> it is pointed to from the xhtml namespace document

Ralph: It is up there, somewhere - the XHTML namespace document points to it.
... Where is http://www.w3.org/ns/rdfa/ used?

ShaneM: It shouldn't be circulating, nothing should point to it.

<ShaneM> http://www.w3.org/1999/xhtml/

<benadida> http://www.w3.org/1999/xhtml/Overview.xhtml

<benadida> (2 days younger)

<benadida> http://www.w3.org/2008/07/rdfa-xslt

ShaneM: Ralph/Steven or I will fix this.
... The contents of both those documents should be exactly the same.

<ShaneM> ACTION: fix the .htaccess for the XHTML namespace [recorded in http://www.w3.org/2009/01/08-rdfa-minutes.html#action01]

Action Items

<benadida> action items --> http://www.w3.org/2008/12/18-rdfa-minutes.html#ActionSummary

ACTION: Mark to review reasoning on setting explicit about="" on HEAD and BODY [recorded in http://www.w3.org/2008/12/18-rdfa-irc] [CONTINUES]

ACTION: Ben to add public-rdfa examples to wiki and think of slightly improved top-level organization [recorded in http://www.w3.org/2008/11/06-rdfa-minutes.html#action11] [CONTINUES]

ACTION: Ben to put up information on "how to write RDFa" with screencast possibly and instructions on bookmarklet. [recorded in http://www.w3.org/2008/11/06-rdfa-minutes.html#action12] [CONTINUES]

ACTION: Jeremy to demonstrate GRDDL with XHTML/RDFa once the NS URI is set up. [recorded in http://www.w3.org/2008/09/11-rdfa-minutes.html#action03] [CONTINUES]

ACTION: Manu talk with Jamie McCarthy about an AskSlashdot piece [recorded in http://www.w3.org/2008/09/11-rdfa-minutes.html#action04] [CONTINUES]

ACTION: Manu to write summary for Semantic Web Use Cases for Ivan. [recorded in http://www.w3.org/2008/09/11-rdfa-minutes.html#action09] [CONTINUES]

ACTION: Manu write the perl code for Slashdot. [recorded in http://www.w3.org/2008/09/11-rdfa-minutes.html#action11] [CONTINUES]

ACTION: Mark create base wizard suitable for cloning [recorded in http://www.w3.org/2008/09/11-rdfa-minutes.html#action12] [CONTINUES]

ACTION: Mark to send Ben ubiquity related wizard stuff [recorded in http://www.w3.org/2008/11/20-rdfa-minutes.html#action11] [CONTINUES]

ACTION: Mark write foaf examples for wiki [recorded in http://www.w3.org/2008/09/11-rdfa-minutes.html#action13] [CONTINUES]

ACTION: Michael to create 'RDFa for uF users' on RDFa Wiki [recorded in http://www.w3.org/2008/09/11-rdfa-minutes.html#action14] [CONTINUES]

<mhausenblas> http://semanticweb.org/wiki/Microformats_in_RDF

Manu:2 parts
... part 2 is "If I've already setup my page to use hCard, how do I switch to RDFa?"

Michael: split it into two parts (how and differences)

Manu: Perhaps we need something that shows general differences between uF and RDFa, and then gives specific examples.

ACTION: Ralph think about RSS+RDFa [recorded in http://www.w3.org/2008/09/11-rdfa-minutes.html#action15] [CONTINUES]

Test Cases

<msporny> public-rdf-in-xhtml-tf/2009Jan/0016.html Test Case #121: "[prefix:]" CURIE format is valid

Manu: the issue tested here is with suffix-less CURIEs, e.g. "example:"
... CURIE still expands, empty-string as suffix.

<Ralph> +1

<mhausenblas> +1

<ShaneM> +1

RESOLUTION: test case 121 suffix-less CURIE approved

<msporny> http://lists.w3.org/Archives/Public/public-rdf-in-xhtml-tf/2009Jan/0017.html Test Case #122: "[:]" CURIE format is valid

<mhausenblas> +1

<Ralph> +1

<benadida> +1

<ShaneM> +1

<markbirbeck> +1

<msporny> +1

RESOLUTION: test case 122 prefix and suffix-less CURIE [:] approved

<msporny> public-rdf-in-xhtml-tf/2009Jan/0018.html Test Case #123: "[]" is a valid safe CURIE

<mhausenblas> public-rdf-in-xhtml-tf/2009Jan/0026.html

<msporny> about="[foo]"

Manu: the current consensus is that the subject is http://example.org/

<msporny> about="[]"

Manu: "[foo]" is an invalid CURIE, therefore so should be the empty string
... as neither is in the reserved (XHTML) list

<msporny> # 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;

Ben: did we define CURIES to require a prefix in RDFa?

Mark: yes
... wasn't my preference, but it was a long discussion

Ben: considering consistency w.r.t. reserved words
... this is the first instance where an invalid value actually changes the structure

Mark: and Ivan pointed out the same thing occurs with @about="[foo]"

Shane: right; @about="[foo]" should not change the subject

Ben: but the presence of @rel alters the graph structure even if the CURIE is not valid
... however in this case it's acting as if @about was not present
... however, since @about just changes the subject and doesn't by itself generates triples, maybe this is OK

Mark: it's clear that this is the current spec. We could discuss whether this is the most desireable choice.

Ben: so if it's not a valid CURIE value, the behavior is as if @about were not there

Mark: the alternative discussed was to assume the invalid CURIE was in the local document namespace
... and we liked that less

Ben: the discussion is about the subject; some triple has to be generated, and the spec is clear

Mark: however, as you note @rel="[foo]" does do some work

Ben: rephrasing, what is the alternative when an invalid CURIE is found?
... it would seem wrong to drop the triple entirely
... whereas it's more reasonable to drop the triple in @rel="[foo]"
... so I don't see a better alternative for @about="[foo]" without major changes to CURIE
... I'm satisfied with this conclusion

Mark: the test case seems to be unnecessarily nested

Manu: yeah, probably; it went through several iterations

Mark: the middle DIV could probably be dropped
... you only need the first one

Manu: yeah, it appears the <div about="http://example.org/"> could be dropped
... the correct SPARQL should be ...

Shane: do you agree, Mark, that the same rules apply to @resource, @href, @src?

Ben: only @resource uses SafeCURIE

<msporny> Here's the updated case:

Shane: assuming that it is possible to create an illegal URI then the general rule would hold that an illegal URI is ignored

Mark: yeah

Shane: @href and @src?

<msporny> ---------------------Test Case 123 XHTML--------------------------

<msporny> <!DOCTYPE html PUBLIC "-//W3C//DTD XHTML+RDFa 1.0//EN"

<msporny> "http://www.w3.org/MarkUp/DTD/xhtml-rdfa-1.dtd">

<msporny> <html xmlns="http://www.w3.org/1999/xhtml"

<msporny> xmlns:dc="http://purl.org/dc/elements/1.1/">

<msporny> checks to make sure RDFa processors resolve the empty

<msporny> CURIE correctly.

<msporny> <span property="dc:contributor">Shane McCarron</span>

<msporny> contributed to this test.

<msporny> -----------------------------------------------------------------

<msporny> ---------------------Test Case 123 SPARQL -----------------------

<msporny> ASK WHERE {

<msporny> "Test Case 0123" .

<msporny> "Shane McCarron" .

<msporny> }

<msporny> ----------------------------------------------------------------

Shane: @href and @src are evaluated the same way

<msporny> +1

<markbirbeck> +1

Ben: +1

<mhausenblas> +1

RESOLUTION: test case 123 with [] invalid CURIE approved

<ShaneM> +1

<Ralph> +1, though recommend changing the SPAN content to give a semantically less confusing title

ACTION: Manu to create TC to test @resource="[]" does not set object based on TC 123. [recorded in http://www.w3.org/2009/01/08-rdfa-minutes.html#action14]

comment from december about test suite:

ACTION: Manu to look at http://lists.w3.org/Archives/Public/public-rdf-in-xhtml-tf/2008Dec/0037.html [recorded in http://www.w3.org/2009/01/08-rdfa-minutes.html#action15]

Manu: Didn't have time to look at it in depth.

<benadida> consensus from dec 4th:

<benadida> so I think we have consensus about @prefix='p1=u1 p2=u2 ...'

<benadida> ... and that @prefix='=u1' seems not to have value

<benadida> ... and @prefix='u1' may have value and should be further investigated

<benadida> --> http://www.w3.org/2008/12/04-rdfa-minutes.html#item02

keyword bundles and HTML4-compatible RDFa

benadida: We agree that there needs to be some non-xml based approach to declare namespaces. Should it be called @prefix?
... We need to make that decision.
... We should confirm the idea that a "with" statement is not useful. We drop the idea of @prefix="=u1".
... If we want to provide bundles, are they bundles of reserved words, or more involved transformations.

markbirbeck: I don't think we finalized whether the syntax within the attribute is "a=b" or "a:b" or something else.
... If it is some sort of transformation, it would be a set of transformations defined using RDF.
... Fresnel is one example of this approach.
... Transformations are out of scope in a way, we don't need to overload the RDFa parsing algorithm.

benadida: Do you have a draft of your deeper thoughts about this issue?

markbirbeck: I'm a bit weary of discussing this off-list, prefer to have the discussion in the public.
... We're keen to address the issue

benadida: I agree.

markbirbeck: I like "keyword bundle"

benadida: It would be good to see how all this stuff plays together.

ShaneM: These should be two separate topics. @prefix is one, keyword bundles is the other.

benadida: Any other decisions that we need to make that are missing?

markbirbeck: there isn't any particular reason that we couldn't end up with two more attributes.
... We could agree on @prefix and get that done.
... @token and keyword bundles could use another attribute.
... and it could come later.

<ShaneM> oooh - we could introduce curie-xxx attributes just to irritate people in the tag (that was sarcasm!)

@token would be used to specify these values at run-time.

server-curie-xx

benadida: We do have a proposal on the table for @prefix, prefix="p1=u1 p2=u2"

markbirbeck: There are some benefits to have @prefix in the HEAD - it could be argued that it should apply in the BODY.

ShaneM: Didn't we talk about using LINK to specify that?

markbirbeck: Yes, or we could extend it in some other way - a new element or attribute.

<ShaneM> I agree that having prefix / keyword bundles in the head that apply to the entire document makes sense.

Ben: regrets for 22 Jan
... next meeting: 22 Jan

RDF in XHTML 1.0 Task Force

08 Jan 2009

Attendees

Contents

RDFa NS URL

Action Items

Test Cases

comment from december about test suite:

keyword bundles and HTML4-compatible RDFa

Summary of Action Items