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Re: Viewport and nested selected nodes

From: Richard Tobin <richard@inf.ed.ac.uk>
Date: Mon, 23 Oct 2006 18:32:37 +0100 (BST)
To: Norman Walsh <Norman.Walsh@Sun.COM>, public-xml-processing-model-wg@w3.org
Message-Id: <20061023173237.C6EED11EDD0@macpro.inf.ed.ac.uk>

> | 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.

-- Richard
Received on Monday, 23 October 2006 17:32:49 GMT

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