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

Maciej Stachowiak, Wed, 17 Mar 2010 00:27:42 -0700:
> 
> On Mar 16, 2010, at 11:34 PM, Leif Halvard Silli wrote:
> 
>> Maciej Stachowiak, Tue, 16 Mar 2010 22:15:16 -0700:
>> 
>>> The former is essential, and separate
>>> from any differences in processing that DOM. The latter will not be
>>> achieved by Robert's proposal and is probably not practical for
>>> various edge case reasons.
>> 
>> Vendor prefixes would then be an edge case?
>> 
>> What I meant was that if an attribute prefix lives in a namespaces
>> according to one user agent, but not according to another (which could
>> be a possibility in text/html, even if it may not be possible in
>> XHTML), then a prefixed attribute "leave" on the DOM tree could be
>> targeted, via CSS, like this,
>> 
>> 	[*|attribute]{}
>> 
>> in the UA that sees it as a namespace. And like this,
>> 
>> 	[namespace\:attribute]{}
>> 
>> in an UA which doesn't see the namespace.  May be this difference is
>> what you refer to as the "produced DOM"? And I argue that one cannot
>> avoid this difference, when it comes to vendor prefixes.
> 
> I could be misunderstanding, but my reading of Robert's Proposal X is 
> that it would always place attributes in the namespace specified by 
> the relevant xmlns declaration, regardless of whether the browser has 
> special knowledge of a particular prefix. (Or if there is no 
> namespace declaration in the document, the attribute would end up in 
> the null namespace). Thus, which of the above selectors matches would 
> be consistent in all browsers for any given document, assuming all 
> browsers implement Proposal X.

I read what he says. I claim that it isn't as he (and you) say.

Let's say we have a Webkit specific style attribute:

	-webkit:style="color:red"

I suppose internally, Webkit would use its regular CSS interpreter. 
Hence Webkit see this attribute as being in the "@style namespace". 
Whereas other vendors do not.

>> Effectively, in text/html, then a vendor specific namespace could be
>> implemented without the use of a prefix - one could simply do this:
>> 
>> 	<div -wexbkit="value">
>> 
>> Those that support the -webkit namespace could then see it (in CSS) as
>> 
>> 	[*|-webkit]
>> 
>> Or as
>> 
>> 	[webkitnamespace|-webkit]
>> 
>> whereas the others could target it as
>> 
>> 	[-webkit]
> 
> Robert's Proposal Y would not place prefixed attributes in a 
> namespace (other than the null namespace). Thus, in all browsers, 
> only an attribute selector with no prefix specified would match.

So effectively, it would not be a vendor specific prefix? It is all 
just a promise from the other browsers: "No, we will not react to 
[-webkit] even if we see it" ?
-- 
leif halvard silli

Received on Wednesday, 17 March 2010 14:27:03 UTC