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Re: HTML+RDFa Issues (update)

From: Steven Pemberton <Steven.Pemberton@cwi.nl>
Date: Thu, 02 Jul 2009 17:01:31 +0200
To: "Mark Birbeck" <mark.birbeck@webbackplane.com>, "RDFa mailing list" <public-rdf-in-xhtml-tf@w3.org>
Message-ID: <op.uwf30trfsmjzpq@steven-750g>
Agree, cancel.

Nice quote from Guus Schreiber about RDFa that you tweeted by the way Mark.

Steven

On Thu, 02 Jul 2009 16:48:30 +0200, Mark Birbeck  
<mark.birbeck@webbackplane.com> wrote:

> To those that are left, is there any point in having a call? I'm not
> sure there is much we can do.
>
>
> Regards,
>
> Mark
>
> On Thu, Jul 2, 2009 at 7:19 AM, Ben Adida<ben@adida.net> wrote:
>>
>> Hi folks,
>>
>> I thought I'd be able to make it to the call this week, but last minute
>> stuff before a short 4th of july trip are making it impossible, so
>> regrets from me.
>>
>> I'll write some thoughts on Manu's points below after the (US) holiday
>> weekend :)
>>
>> -Ben
>>
>> Manu Sporny wrote:
>>> We had a fairly productive discussion last week (draft minutes[1])
>>> regarding the most pressing issues surrounding HTML+RDFa. A brief
>>> summary of the findings can be found here:
>>>
>>> http://rdfa.info/wiki/rdfa-in-html-issues#RDFa_Task_Force_Discussion_Order
>>>
>>> Regrets for the call tomorrow, I won't have Internet access.
>>>
>>> Some quick thoughts on the next set of issues:
>>>
>>> == Processing of xmlns:* in non-XML languages ==
>>>
>>> I think that we should phase out xmlns:* for the following reasons:
>>>
>>>  * There is a case-sensitivity issue when used in HTML4 markup.
>>>  * It's technically feasible, but has led to a number of
>>>    namespace rants and "polluting HTML4/5 with namespaces" rants.
>>>
>>> We could replace xmlns:* with @prefix or Mark's upcoming @token
>>> proposal. xmlns:* should exist for backwards compatibility, but we  
>>> could
>>> suggest that it may be phased out in future versions of RDFa and should
>>> not be used for new markup.
>>>
>>> == Case sensitivity for xmlns: attributes and prefixes in attribute
>>>    values ==
>>>
>>> As Shane has mentioned previously, we should immediately update the
>>> XHTML+RDFa errata document to say that all prefixes specified by xmlns:
>>> should be lower-case. In other words, authors SHOULD NOT use mixed case
>>> for prefixes. Therefore, doing the following would be frowned upon:
>>>
>>> xmlns:Foo or xmlns:FooBar or xmlns:FOOBAR
>>>
>>> the suggested markup should be:
>>>
>>> xmlns:foo or xmlns:foobar or xmlns:foobar
>>>
>>> I agree with Shane's assessment: I don't think we need to change the
>>> parsing rules to lower-case prefix names in xmlns:. We should provide
>>> guidance to authors so that if they want to create markup that works in
>>> both HTML and XHTML, they should not mix case if xmlns: is used.
>>>
>>> This point isn't moot if we transition away from using xmlns:* - we  
>>> will
>>> still need to provide guidance for those that continue to use xmlns:*  
>>> in
>>> XHTML1.1 documents.
>>>
>>> = Use of regular CURIEs in @rel =
>>>
>>> I believe that Julian Reschke has raised this issue several times. I
>>> don't remember the technical issue and I remember Ben stating clearly
>>> that there isn't a technical issue.
>>>
>>> I don't have any input on this at the present time. Clearly, if a
>>> technical issue exists with CURIEs in @rel - we must address it.
>>>
>>> = Script-based modification of DOM =
>>>
>>> If we include language to address this issue in an XYZ+RDFa document,
>>> the language should be minimal.
>>>
>>> The only time that RDFa enters the picture is when the
>>> (X)HTML/Javascript model/control layer serializes/streams the (X)HTML
>>> document into/to a tree model and hands it off to the RDFa parser. The
>>> RDFa parser shouldn't have any knowledge of how the tree model is
>>> generated - but we shouldn't be strict about making this point.
>>>
>>> Re-parsing can be done whenever a DOM changed happens, on a X second
>>> timeout basis, or at the leisure of the browser - for example, when CPU
>>> usage is low.
>>>
>>> If this is a question of /when/ the RDFa parser should be called, our
>>> answer should be "whenever the application layer wants to run the RDFa
>>> parser".
>>>
>>> If this is a question of /how/ the RDFa parser should be called, we
>>> shouldn't go to great lengths to specify how that is done. For example,
>>> if speed optimizations for incremental DOM parsing of an HTML document
>>> (versus complete parsing of the HTML document) are desired - the
>>> implementation is up to the implementer of the incremental RDFa parser
>>> (which would need specific hooks into the DOM layer and vice versa).
>>>
>>> The important part is that the triples that are generated via an
>>> incremental RDFa parser should be exactly the same as if the document
>>> was parsed fully. I don't think we need to specify much more than that.
>>>
>>> -- manu
>>>
>>> [1] http://www.w3.org/2009/06/25-rdfa-minutes.html
>>>
>>
>>
>>
>
>
>
Received on Thursday, 2 July 2009 15:02:17 GMT

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