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[Bug 4446] [XQuery] 2.3.4 Equivalent expressions

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Date: Sun, 17 Jun 2007 22:19:33 +0000
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To: public-qt-comments@w3.org
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http://www.w3.org/Bugs/Public/show_bug.cgi?id=4446





------- Comment #6 from hrennau@yahoo.de  2007-06-17 22:19 -------
(In reply to comment #3)
> I think the behaviour you're
> concerned about is for the processor to *always* return true() for this
> example. 
> ...
> How about "... MUST NOT evaluate a branch that is not selected" ?

It seems to me the problem is that the processor might skip the evaluation of
the condition. If so, your proposal would less reliably enforce the execution,
as compared to the wording of Michael Kay (if I understand it correctly, see
comment #5).

As an example, consider the case that the conditional expression is operand of
the fn:count function, and that both branches consist of function calls whose
signature guarantees exactly one result item. It seems to me that your wording
would permit to rewrite the conditional expression as the expression "1",
whereas the original proposal would not allow such a rewrite, because it would
amount to returning the result of a branch that has not been selected. 
Received on Sunday, 17 June 2007 22:19:38 UTC

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