Re: [xsl] Inconsistency in descendant:: expressions?

Subject: Re: [xsl] Inconsistency in descendant:: expressions?
From: Peter West <lists@xxxxxxxxx>
Date: Sun, 4 Aug 2013 20:36:11 +1000
See below.

Peter West

"Ask and it will be given you; seek, and you will find; knock, and it will be
opened to you."

On 04/08/2013, at 7:05 PM, Martin Honnen <Martin.Honnen@xxxxxx> wrote:

> Peter West wrote:
>> I'm using Oxygen 15.0 with Saxon PE 9.5.0.2 XSLT 2.
>>
>> My XSLT is rusty, and I was struggling with the expression of particular
descendant expression. After a number of botched attempts, I cam up with two
versions that seemed to work. (Yes, I will use the ancestor:: axis, but I want
to know what is happening here.)
>>
>> The following code operates on an xhtml document.
>
> It would help if you posted a minimal but complete document allowing us to
reproduce the problem.
>
>
>> 1)  <xsl:variable name="table-node" select="//*:table[//*:tr[count(*:td) =
3]][1]"/>
>
> Are you sure that you want
>  //*:tr
> inside of the predicate and not
>  .//*:tr
> ?
> Your current versions looks at all *:tr elements in the document, not at the
*:tr descendants of the *:table element you are applying the predicate to.

yes, I want .//*:tr.  It worked because there is only one table in the file I
was using.  I've fixed that, but it that doesn't change the result.
>
>> 2)  <xsl:variable name="table-ancestors"
select="//*[descendant::node()=$table-node]"/>
>
> You compare the string value of a table element to other nodes, is that what
you want? The ". is $foo" which checks node identity you have below in 3)
seems more meaningful to me.

Ok. The penny has dropped. The select is supposed to find all nodes from the
root that have a particular <table> node as a descendant. In the case above,
the node() string value is compared to the string value of the <table> node;
that node matches. However, the string value of the <tbody> node also matches,
so the <table> has such a descendant,

Thanks!


>
>
>> 3)  <xsl:variable name="table-parents" select="//*[descendant::node()[. is
$table-node]]"/>

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