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Re: [css3-namespace] what is a "no namespace"

From: fantasai <fantasai.lists@inkedblade.net>
Date: Mon, 18 Feb 2008 19:05:36 -0800
Message-ID: <47BA4780.8060206@inkedblade.net>
To: Christof Hoeke <csad7@t-online.de>
CC: Www-style <www-style@w3.org>

Christof Hoeke wrote:
> 
> hello,
> a comment to the last call of the CSS Namespace spec but actually I 
> always wondered a bit if it could be explained a bit more clearly what 
> "no namespace" means?
> 
> --- another thing first:
> 
> While writing this comment I originally had the following thought:
> 
>     In XML no namespace means
>      1. elements with no prefix and no default namespace in the 
> enclosing document/element
>      2. elements resetting a default namespace defined in the enclosing 
> document/element with::
>     
>     <x xmlns="">...
> 
> Using this simple logic it would be allowed to define::
> 
>     @namespace empty "";
> 
> to select element x from above with::
> 
>     empty|x
> 
> But in XML the empty string is not allowed when defining a namespace 
> with a prefix (http://www.w3.org/TR/xml-names/#iri-use), only when 
> defining the default namespace (if I understand 
> http://www.w3.org/TR/xml-names/#defaulting right).
> 
> So the above should not be valid in CSS either I guess?
> The syntax does not prevent this though and no comment is there either 
> (maybe I overlooked it?).

Added to the issues list. Anne or I will get back to you on this one.
   http://dev.w3.org/csswg/css3-namespace/issues-2

> Anyway, I also think the term "no namespace" should be more explicit. In 
> an very old draft 
> (http://www.w3.org/1999/06/25/WD-css3-namespace-19990625/#tag-selector) 
> I found the sentence:
> 
>     The namespace component may be left empty to indicate that the 
> selector is only to match elements with no declared namespace
> 
> Maybe the single word "declared" could be re-added to 
> http://www.w3.org/TR/css3-namespace/#css-qnames to make this clearer?

I borrowed some wording from Namespaces in XML and clarified it as

     The prefix of a qualified name may be omitted to indicate that the name
     belongs to no namespace, i.e. that the namespace name part of the expanded
     name has no value.

Does that work for you?

~fantasai
Received on Tuesday, 19 February 2008 03:05:26 GMT

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