Re: [css3-namespace] Last call comments from XHTML2 WG

fantasai wrote:
> 
> Steven Pemberton wrote:
>>
>> On Fri, 28 Mar 2008 16:18:04 +0100, Bjoern Hoehrmann 
>> <derhoermi@gmx.net> wrote:
>>> Mark asked for guidance on how to choose between multiple methods, that
>>> request is sound and already addressed in the right place. You on the
>>> other hand assert that default namespace declarations in style sheets as
>>> proposed in the draft come as a surprise and special attention needs to
>>> be drawn to this surprise. I don't think there is any surprise, and thus
>>> have a hard time to understand exactly how we could address the concern.
>>> If you could propose specific edits, that would be most helpful.
>>
>> I didn't say it was a surprise. I said it was contrary to an axiom of 
>> CSS up to now that future additions to CSS don't change how previous 
>> parts of the language work. That is part of the forward-compatible 
>> parsing rules of CSS:
>>     If I apply the forward-compatible parsing rules to a CSS(n+1) 
>> stylesheet, stripping it of its CSS(n+1) features, I will get a CSS(n) 
>> stylesheet. None of the rules left change their meaning in the process.
>>
>> This has always been true in CSS, and the namespace selectors spec 
>> changes this.
>>
>> A note pointing out that default namespaces alter the way that type 
>> selectors work compared with earlier versions of CSS, and if you want 
>> to avoid that you should always use explicit qualified names would do 
>> the trick.
> 
> I don't mind adding a note pointing to the Selectors module here. I'm
> opposed to making any normative changes or giving any unsound advice,
> but clarifying the situation shouldn't be a problem imho.
> 
> I'd rather add a pointer and not repeat the entire explanation, though,
> if that's ok. :) Especially since the issue is technically out-of-scope
> for this particular module: the Selectors module is where default
> namespaces are defined to apply to type selectors.

Added

   <p class="note">Note that using default namespaces in conjunction with type
     selectors can cause UAs that support default namespaces and UAs that don't
     support default namespaces to interpret selectors differently. See
     <a href="http://www.w3.org/TR/css3-selectors/#downlevel">Namespaces and
     down-level clients</a> in the Selectors module [[SELECT]] for details.</p>

Let me know what you think.

~fantasai