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Re: Viewport and nested selected nodes

From: Alex Milowski <alex@milowski.org>
Date: Mon, 23 Oct 2006 19:37:29 -0700
Message-ID: <453D7C69.9000604@milowski.org>
To: public-xml-processing-model-wg@w3.org

Richard Tobin wrote:
>> | I think that viewport should probably filter the selected nodes to
>> | only those that do not have another selected node as a descendant.
> 
>> I had the opposite strategy in mind, where the filter selects the
>> "outermost" matching nodes and ignores nested matches.
> 
> It would be good to be able to stream if possible, and in this case
> that means matching the XPath against nodes, rather than evaluating
> a expression from the root and getting a node set back.
> 
> If you do that, and we specify that the innermost match is used, the
> implementation has to inspect the descendants of matches even in cases
> where there won't in fact be a matching descendant.  If we use the
> outermost one, this case will be more efficient.

Good point.

It would really lobotomize my ability to stream large documents if
we had to deliver the inner matches.

--Alex Milowski
Received on Tuesday, 24 October 2006 02:37:50 GMT

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