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Re: XBL: syntax to use for includes attributes.

From: Robin Berjon <robin.berjon@expway.fr>
Date: Mon, 06 Dec 2004 16:54:09 -0500
Message-ID: <41B4D501.2030607@expway.fr>
To: Elliotte Harold <elharo@metalab.unc.edu>
Cc: www-svg@w3.org

Elliotte Harold wrote:
> The draft says, "The XBL task force has not yet decided the syntax to 
> use for includes attributes." and requests feedback on this issue, so 
> here you go.

Thanks!

> My feeling is that full XPath 1.0 is a minimum syntax for the includes 
> attributes. I assume the context node for the XPath expression would be 
> the matched node.

I can't speak for the whole TF but I believe that whichever route we go 
at this point, it'll be oriented more towards a subset of either XPath 
1.0 or CSS Selectors, rather than the full thing (and quite certainly 
not something more powerful).

> However, I really wonder if this goes far enough. I can foresee a lot of 
> use cases that need something Turing complete. For instance, you might 
> want to place each subsequent ten nodes in a different box. I can't see 
> how to do that with just XPath when you don't know the number of nodes 
> in advance.

I think you're missing something. The use case you seem to describe 
would imho include * (or none) in the shadow tree of the parent, and 
then use the script attached to the component to generate the n boxes. 
The intent of includes is not to be or become Turing complete but rather 
to address the simple cases simply. Anything Turing-complete can then be 
layered on top of that using script.

-- 
Robin Berjon
Received on Monday, 6 December 2004 21:54:49 GMT

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