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Re: Inability of location steps to support multiple axes

From: Oliver Becker <obecker@informatik.hu-berlin.de>
Date: Wed, 10 Sep 2003 14:04:49 +0200 (MEST)
Message-Id: <200309101204.h8AC4nta001855@mail.informatik.hu-berlin.de>
To: public-qt-comments@w3.org, emerson@harvestman.net


> As you can plainly see from (http://www.w3.org/TR/xpath20/#doc-StepExpr)
> the Xpath 2.0 specification does
> Not allow anything other than axis/node-test specifiers within a
> location step.

A StepExpr could be a FilterStep which in turn could be a PrimaryExpr
with empty Predicates etc ...

I wrote:
> The parse tree for that is a little bit lengthy, but basically you can
> reduce a StepExpr -> PrimaryExpr -> ParenthesizedExpr -> ...
> -> '(' OrExpr ')' -> ... (many steps using always the first non
> terminal) ... 
> -> '(' UnionExpr ')'
> -> ... -> '(' PathExpr '|' PathExpr ')'
> There you are!

Oliver


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|  ob|do        Dipl.Inf. Oliver Becker                             |
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Received on Wednesday, 10 September 2003 08:04:56 UTC

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