Re: HTML extensibility framework

On Wed, 18 Mar 2009 01:11:46 +0100, Larry Masinter <>  
> Extension methods include:
> 0) new MIME type & new namespace
> 1) same MIME type & new namespace
> 2) new MIME type & old namespace
> 3) same MIME type & same namespace
> In case (3), you definitely need also one of the
> following (and can use these in other cases):
>    new element
>    different DOCTYPE
>    add a processing instruction
>    add a version attribute
>    add a version element
>    add comments or other indications of versioning
>    add a script which adds the processing
>    link new content with a new URI scheme
>    link new content with a URI to new content

Why do you need anything at all? Extensions added to HTML and CSS work  
fine without versioning. JavaScript has little versioning for some syntax  
changes but in general has no versioning either.

(I tend to think that languages that are incrementally improved upon by  
multiple parties and are widely deployed are much better off without  
versioning. Then again, everyone has different ideas as to what versioning  
means. Some feel it's just a hint for the validator. Some think user  
agents need different processing models. Etc.)

Anne van Kesteren

Received on Wednesday, 18 March 2009 00:41:42 UTC