RDF-in-XHTML Task Force

Manu: what happens after end of December? Keep meeting?

Ralph: SWD WG expects to resolve to ask for SKOS CR transition by 16 December and then I will ask for a 4-month extension to SWD WG charter
... this would allow us to formally continue to talk about RDFa futures
... on a personal level, I think it would be a mistake to change RDFa until there is clear support for a proposed change within the HTML WG

Manu: it would be nice to be able to say "here is what we think should be done"
... especially for the microformats community
... we'd be in a stronger position w.r.t. conversations with microformats if we said we think @prefix and external profiles are a good direction

Ben: what's the goal of such a statement? would you hope that people start to use RDFa with @prefix?

Manu: yes, I think the community is stuck
... this has to do with vocabulary development
... the community is currently spending a lot of time on issues that RDFa already solves

Ben: I think it works better to have a proposal with community support to present to W3C rather than to expect W3C to pull the community

Shane: we do talk about HTML5 a lot but it doesn't exist yet -- it's only a Working Group

Ben: there are features of HTML5 that browsers do currently deploy

Shane: none of these deployed features have anything to do with microformats

Ben: call it whatever; we know there is desire to deploy RDFa in HTML without @xmlns
... in the end, we'll have the same proposal for HTML
... so the thing we ought to do is show how to deploy RDFa in HTML4 now, get it to validate, etc.

Manu: yep

<ShaneM> topics - validation in non-xml documents, definition of non-prefixed items, changing of default prefix on the fly

<ShaneM> @prefix SOLVES the problem of validating in non-xml documents. it is INDEPENDENT of the other two topics IMHO

<ShaneM> the ability to extend the collection of non-prefixed terms is interesting, but NOT REQUIRED.

<ShaneM> changing the default prefix on the fly is a CHANGE to RDFa overall, independent of whether a document is XML or not, and whether it uses @prefix or not

<ShaneM> hmm - that might not be true. I think you MUST use @prefix if you want to change the default CURIE prefix.

-> Tuesday SWD WG telecon discussion of charter extension

Action Items

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

ACTION: [DONE] Shane to update the errata document to reflect that step 6 has extra text about a new subject - also respond to Johan who sent private mail, copying the task force. [recorded in http://www.w3.org/2008/11/20-rdfa-minutes.html#action15]

ACTION: [PENDING] 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]

Ben: I've done part of this, still need to update wiki

ACTION: [PENDING] 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]

Ben: I've made a bit of progress on this
... reactions to the new wiki layout?

Manu: new layout is better than the old

ACTION: [PENDING] 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]

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

Manu: I've been hoping to implement it first :)

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

<msporny> http://rdfa.digitalbazaar.com/bitmunk-case-study/

Manu: I wrote a draft but Ivan wants a rewrite
... draft explains what our company is doing
... Ivan would like this draft posted as a longer story and a shorter version for the use case wiki

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

Manu: basically modifying their templates but it's a bit more involved
... adding SIOC

Ben: how about roping Steve Williams from digg into this?
... perhaps just tell him what you're thinking
... digg is also thinking about SIOC
... so showing them your vocabulary ideas could be a useful trigger

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

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

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

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

@prefix

Ben: Mark has a draft blog post on @prefix

Shane: there are several topics and they're independent
... we could come up with credible solutions on pieces
... 1. defining prefix mappings in non-XML grammars
... we've proposed @prefix and a syntax; everyone seems to be onboard, with some semantic extensions

Ralph: do the inheritance rules for @prefix exactly match those for @xmlns?

Shane: I was looking at default namespaces as they relate to CURIEs
... that's a separate topic

Ben: there seemed to be some different between HEAD and BODY rules
... did I read too much into the discussion?
... given that HTML allows metadata in HEAD ...

Shane: at that time we were talking about using <link @rel='prefix' ...> and that's a separable issue

Ben: so current @prefix thinking is that inheritance works exactly like @xmlns?

Shane: yes

Ben: I think we could agree on a syntax like @prefix='a=URI1 b=URI2 ...'

Manu: there was a notion that @prefix might hold more than just what is in this document
... there was also a question of what happens in @prefix='URI'
... i.e. default prefixes, or a vocabulary that could be pulled-in to define other prefixes

Ben: pulling in another vocabulary wouldn't conflict with this syntax

<ShaneM> http://rdfa.info/wiki/RDFainHTML4#Prefix_Mappings

Shane: the wiki page supports these sorts of extensions
... could debate whether it makes sense to redefine the default prefix

Ben: I agree the three items under 'Future Handling' can be considered separately
... Mark was thinking about something that would pull in a local vocabulary for one section of a document

Shane: want to separate the topics; validating v. changing the extensibility model of RDFa

Ben: I believe there is consensus on the first bullet; @prefix='prefix=URI'
... I don't see consensus on the second bullet @prefix='=URI'

Manu: microformats added bullets 2 and 3 because we didn't feel @profile was the place to extend RDFa functionality
... this is more in the 3rd bullet; extensibility via @prefix or via @profile
... the issue of setting the default namespace is in both worlds

Ben: if we want to make it easy to markup common formats, such as a page on a social network, will we want to be able to pull terms from multiple vocabularies?
... if so, the way to simplify this is not by defining lots of prefixes but to include pre-packages bundles of terms

Manu: so maybe the 2nd bullet is unnecessary

Ben: yes, 2nd could be subsumed in 3rd
... but 2nd is also a trivial generalization of 1st bullet
... however, this also makes @prefix do more than @xmlns [which we might not want]
... I like simplifying the social network bundle of terms case

Manu: I can't think of a strong use case for bullet 2 given that we implement 1 and 3

Ben: right, could have a bundle that only uses 1 vocabulary, so little marginal value to bullet 2

Manu: bullet 2 came before we'd thought out bullet 3 completely

Shane: I don't agree with Mark's approach; I think it's overly simplistic
... it doesn't takes advantage of the essential RDF-ness of the environment
... and it doesn't really address the microformat case in a way that makes it easy to extend XMDT

<ShaneM> http://rdfa.info/wiki/RDFa_Vocabularies#Discovering_new_unprefixed_CURIEs

Shane: Manu wrote a separate proposal ^^
... making it easy to markup microformat definitions in a way that defines vocabulary terms
... whatever we do here should be grounded in RDF

Ralph: yay Shane!

Shane: unless he's changed his approach, Mark was defining a way to map prefixes to URIs
... this is using xmlns to define macros, rather than using RDF to define vocabularies
... vocabulary terms need to be grounded in URIs to allow a follow-your-nose processing engine to follow the URIs

Ben: the intermediate document could be RDF

Shane: but Mark hasn't proposed this

Manu: Mark was just showing a technically nifty way to use @prefix to expand terms without having to consult an external document
... but we recognize it would also be helpful to be able to provide an external RDF document that defines prefixes
... I think Mark was opposed to having to load these external documents

Shane: I understand why it might be unattractive to _have_ to load an external document to understand unprefixed CURIEs
... RDF interpretation requires dereferencing prefix mappings, which I maintain has to be done anyway

Ben: Mark was talking about bundles of vocabularies which seems to me to require external documents

Shane: Mark had a syntax for doing this inline in the document, but I don't know why you'd want to bundle this into every document
... Mark did write that this _can_ be embedded locally if there was a consistent syntax

Ben: I see little value in such embedding

Shane: our debate should be about how to derive the meaning, not about the syntax

Ben: so I think we have consensus about @prefix='p1=u1 p2=u2 ...'
... and that @prefix='=u1' seems not to have value
... and @prefix='u1' may have value and should be further investigated

[adjourned]