Re: ISSUE-147 (preserve markup by default): RDFa Processors should preserve markup by default [RDFa 1.1 in HTML5]

On Dec 28, 2012, at 1:26 PM, "Shane McCarron" <ahby@aptest.com<mailto:ahby@aptest.com>> wrote:

I agree with Gregg - this issue was debated ad nauseam two years ago.  At that time we made what we thought was a reasonable decision based upon how semantic data is consumed in the marketplace.  At that same time we said that there should be an HTMLLiteral datatype that could be emitted, but that we didn't know if there would be one.  If there were, it could be used in HTML5+RDFa.  Has such a type emerged?

Yes, there is one now: http://www.w3.org/TR/rdf11-concepts/#section-html


Gregg

On Fri, Dec 28, 2012 at 2:40 PM, Gregg Kellogg <gregg@greggkellogg.net<mailto:gregg@greggkellogg.net>> wrote:
On Dec 28, 2012, at 11:03 AM, RDFa Working Group Issue Tracker <sysbot+tracker@w3.org<mailto:sysbot%2Btracker@w3.org>> wrote:

> ISSUE-147 (preserve markup by default): RDFa Processors should preserve markup by default [RDFa 1.1 in HTML5]
>
> http://www.w3.org/2010/02/rdfa/track/issues/147

>
> Raised by: Manu Sporny
> On product: RDFa 1.1 in HTML5
>
> This issue was raised by Sebastian Heath:
>
> HTML5 and its variants such as XHTML5 provide a rich set of elements that content creators use to indicate many aspects of the texts they are representing. When processing RDF in attributes, the "RDFa 1.1 in HTML5" specification [1] should by default require preservation of all intentional markup. This is good practice. In particular, the working group should not assume that elements in content marked with the @property attribute are there by mistake. Nor should the replication of namespaces in the output be considered garbage.
>
> Full reasoning is here:
>
> http://lists.w3.org/Archives/Public/public-rdfa-wg/2012Dec/0074.html

>
> This issue is being re-opened because of the following statements:
>
> "This is good practice. In particular, the working group should not assume that elements in content marked with the @property attribute are there by mistake. Nor should the replication of namespaces in the output be considered garbage."
>
> The working group should re-examine if:
>
> 1) Preservation of markup is good practice for RDFa Processors.
> 2) The inclusion of HTML markup by authors was not a mistake and the feature is causing problems in RDFa 1.1 based on 6+ months of deployment experience.
> 3) The replication of namespaces should be considered garbage (I don't think the WG ever said this, and the assertion is most likely due to a mis-communication at some point).
> 4) Changing the rules at this point would cause an undue burden on authors and implementers due to conflicting rules between RDFa Core and HTML+RDFa.

If we were to do anything, it would only be for HTML5+RDFa, not XHTML1+RDFa or RDFa 1.1, as that ship has sailed. Furthermore, if this were to change for HTML5+RDFa, rdf:HTML would be a more appropriate datatype then rdf:XMLLiteral IMO.

Relating to 4), changing the rules now would be a major incompatibility with RDFa 1.1, which is explicit for this across all host language, so I think it's probably too late. The rules were changed when RDFa Core 1.1 became a REC, changing them back for HTML+RDFa would make it even more confusing.

This was resolved in May of 2010 [1]; it was also specifically called out in the charter for the RDF Web Applications Working Group [2].

Gregg

[1] http://www.w3.org/2010/02/rdfa/meetings/2010-05-13#resolution_2

[2] http://www.w3.org/2011/03/rdfwa-wg-charter




--
Shane P. McCarron
Managing Director, Applied Testing and Technology, Inc.