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Re: [RDFa] ISSUE-3 @class and @role for rdf:type

From: Mark Birbeck <mark.birbeck@x-port.net>
Date: Thu, 28 Jun 2007 15:29:05 +0100
Message-ID: <640dd5060706280729y78b9b170pdbf7f9d7a952462a@mail.gmail.com>
To: "Ben Adida" <ben@adida.net>
Cc: "Ivan Herman" <ivan@w3.org>, RDFa <public-rdf-in-xhtml-tf@w3.org>, "SWD WG" <public-swd-wg@w3.org>

Hi Ben,

I'm not sure I agree. Sure we've done talks, but the main source of
information for people, going forward, will be the primer and our
various specs. This is pretty much our last chance to get these things
right, so if people think @class is wrong then we should just make the
change as soon as we can. Of course, if there is sufficient argument
for keeping @class then that's just as easy, but the point is that the
existing documentation shouldn't be an argument against making a final
change, if we think that change is right.

Regards,

Mark

On 28/06/07, Ben Adida <ben@adida.net> wrote:
>
> It's important to remember that we agreed that it is too late to change
> @class, since we've published many talks and documents that use it. I
> would strongly vote for not revisiting this. Having an additional
> attribute may be okay to provide an alternative for folks who find
> @class distasteful, but I'm not hugely in favor of it (one way is better
> than two.)
>
> -Ben
>
> Ivan Herman wrote:
> > Mark,
> >
> > as I said: I am not sure about the usage of @role, I did not follow the
> > details of that. I am happy to disregard @role for now.
> >
> > I also agree that rdf:type is important, so it is probably a good idea
> > to give a shorthand (just like Turtle does). @isA sounds perfectly fine
> > to me...
> >
> > Ivan
> >
> > Mark Birbeck wrote:
> >> Hi Ivan,
> >>
> >> I also prefer a new attribute.
> >>
> >> The only thing I feel really strongly about is that we don't use @role
> >> for rdf:type, since I think that will come back to bite us in the
> >> future. So for me, that leaves two choices, use @class or use a new
> >> attribute.
> >>
> >> I can live with using @class, but I do agree that it comes with some
> >> baggage. I don't mean that from the point of view of some kind of
> >> 'backlash', since I think people are using @class semantically already
> >> (even without using microformats). What I mean is that I can easily
> >> imagine people forgetting to put foaf:Person (for example) in the
> >> class attribute on the containing element, since novice authors would
> >> probably see it as 'I must set the CSS class to foaf:Person for this
> >> to work'.
> >>
> >> I also believe that rdf:type is so important that it should be part of
> >> the core RDFa attributes, that are independent of any host language. A
> >> host language may have an additional way of doing this, and we might
> >> even decide in the future to use @class in HTML after all. But by
> >> having our own attribute, it means that there is a core way of marking
> >> up rdf:type that is always there, no matter what language is the host.
> >>
> >> So to summarise; my preferred approach would be to leave @class
> >> undefined for now--we can always come back to this in a future
> >> version--and use @isA or something like that, to indicate the rdf:type
> >> of something.
> >>
> >> Regards,
> >>
> >> Mark
> >>
> >>
> >>
> >> On 28/06/07, Ivan Herman <ivan@w3.org> wrote:
> >>> I am a bit uneasy with the usage of @class. _I know_ that the formal
> >>> semantics of @class allows this type of usage, and I also know that the
> >>> microformat community uses that trick, I still feel that usage @class is
> >>> putting a semantics into the attribute that a lambda user would not
> >>> expect. (And yes, I am also uneasy with the way the microformats reuse
> >>> attributes like title, class, or abbr...).
> >>>
> >>> I would prefer to use a dedicated attribute if we need it (or simply
> >>> stick to the rel="rdf:type", which is at disposal anyway).
> >>>
> >>> I must admit I am not fully familiar with the discussion behind @role to
> >>> decide whether @role should be introduced in RDFa for XTHML1, too, to
> >>> cover this usage, or whether a different @type or similar should be
> >>> introduced. I guess this discussion should start _if_ ISSUE-3 is not
> >>> resolved for @class
> >>>
> >>> Ivan
> >>>
> >>> P.S. Having said all that: I do not consider this issue as life
> >>> threatening:-) Ie, resolving it quickly is probably more important than
> >>> spending lots of time finding the best solution.
> >>>
> >>> Ben Adida wrote:
> >>>> Another issue up for discussion.
> >>>>
> >>>> ISSUE-3
> >>>> http://www.w3.org/2006/07/SWD/track/issues/3
> >>>>
> >>>> The question is what @class and @role should yield in XHTML1.1+RDFa. We
> >>>> don't have complete consensus on this (we specifically note Steven
> >>>> Pemberton's worries about the reuse of the @class attribute), but the
> >>>> current solution, as accepted in the Primer and in many use cases,
> >>> is as
> >>>> follows:
> >>>>
> >>>> @class yields rdf:type only if the value is namespace-qualified. @class
> >>>> contains a space-separated list of values. Only those values which are
> >>>> namespace-qualified yield rdf:type triples.
> >>>>
> >>>> @role does not exist in XHTML1.1, so it is not used here. In XHTML2, it
> >>>> is expected to yield a triple with predicate xhtml2:role.
> >>>>
> >>>> +1 if you agree, otherwise email your disagreements and explanation.
> >>>>
> >>>> -Ben
> >>>>
> >>> --
> >>>
> >>> Ivan Herman, W3C Semantic Web Activity Lead
> >>> URL: http://www.w3.org/People/Ivan/
> >>> PGP Key: http://www.cwi.nl/%7Eivan/AboutMe/pgpkey.html
> >>> FOAF: http://www.ivan-herman.net/foaf.rdf
> >>>
> >>>
> >>
> >
>
>
>


-- 
  Mark Birbeck, formsPlayer

  mark.birbeck@x-port.net | +44 (0) 20 7689 9232
  http://www.formsPlayer.com | http://internet-apps.blogspot.com

  standards. innovation.
Received on Thursday, 28 June 2007 14:29:22 GMT

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