Re: TWO Change proposals for ISSUE-41 : Distributed Extensibility

On Mar 15, 2010, at 8:28 PM, Ennals, Robert wrote:

>
> Proposal Y: tries to give a better fallback and backwards-compat  
> story:
> http://www.w3.org/html/wg/wiki/ChangeProposals/fixedprefixsimple
>

I read over Proposal Y. Because it has no effect on parsing behavior,  
I don't think it suffers from the issue I noticed with Proposal X. Its  
effects seem to be limited to creating an "extended HTML document"  
conformance class and making a (non-normative) recommendation to those  
making extensions, so the details it gives seem sufficient to evaluate  
it on the merits.

I think the rationale for the proposal could be improved by mentioning  
specific scenarios where a party may wish to define an extension to  
HTML, but none of the existing mechanisms would be appropriate. This  
is including data-* attributes, the "other applicable specifications"  
mechanism, as well as metadata mechanisms such as RDFa, Microdata or  
traditional features like class/rel/link/meta. I assume a key point  
here is that these extensions would be expected to affect behavior or  
presentation, but are not suitable for being made a core Web standard,  
at least not yet.

At least one example that I think fits these criteria is experimental  
features in browsers. Browser vendors from time to time want to  
implement features that are not in any specification as a way to  
demonstrate their merits or explore the design space. It would be good  
to have a way to do this without squatting on good names or locking in  
designs that turn out to be suboptimal. So I recommend listing that  
scenario. You may have others in mind.

Regards,
Maciej