Re: [xsl] Template matching preceding-sibling.

Subject: Re: [xsl] Template matching preceding-sibling.
From: "Ilya Konanykhin" <ilya.konanykhin.ml@xxxxxxxxx>
Date: Wed, 14 Nov 2007 15:57:39 +0600
Michael,

thank you for your response and clarification, but you've commented on the question I haven't asked :)

My question is not about correctness of the aforementioned expression and its semantics. I'd like to know how could it be that copy-pasting the Steve's example and running it I obtained a result that was different to what he has got, and actually the result was exactly the same as he wanted to obtain (single string "Ello xslers"), if I understood his request correctly.

I might think that he just simplified his actual case to the very basic one and posted it to the list without checking the output, and in this particular case coincidently it worked according to his will. This leads me to the only conclusion that the responders (Charles, Steve and now you) were deducing the real and more general problem from its particular case description without actually running transformation, otherwise they would obviously got the same result I did, the correct one according to Steve. Am I right? If I am - then ok, I'll just construct another, more general example and will test it (that's exactly where your explanations will fit :)), but if not - it's definetely a reason to find out why one and the same template and input are tranformed on my machine into an output different to what at least several members of the list obtained.

Regards,
Ilya

PS Sorry if the meaning of my writings is hard to get - I'm not that good in English. If I described something unclear - please let me know and I'll try once more.


----- Original Message ----- From: "Michael Kay" <mike@xxxxxxxxxxxx>
To: <xsl-list@xxxxxxxxxxxxxxxxxxxxxx>
Sent: Wednesday, November 14, 2007 2:28 PM
Subject: RE: [xsl] Template matching preceding-sibling.




You're missing that != (like the other comparison operators) returns true if
any item on the left is != to any item on the right. You probably want


not(activity = preceding-sibling::Rec/activity)

but I haven't looked at the problem, it might be that you want

not(activity = preceding-sibling::Rec[1]/activity)

which only looks at the immediately preceding sibling.

Michael Kay
http://www.saxonica.com/

-----Original Message-----
From: Ilya Konanykhin [mailto:ilya.konanykhin.ml@xxxxxxxxx]
Sent: 14 November 2007 04:01
To: xsl-list@xxxxxxxxxxxxxxxxxxxxxx
Subject: Re: [xsl] Template matching preceding-sibling.

Hi, list!
I'm asking for clarification of the topic being on the list
several days ago (Nov 8). Steve <subsume@xxxxxxxxx> wrote:

> I'm missing something fundamental, what is it?
>
> <xsl:template match="Rec[activity !=
preceding-sibling::Rec/activity
> or not(preceding-sibling::Rec)]">  Ello xslers.
> </xsl:template>
>
> <xml>
>    <Rec>
>      <activity>hi</activity>
>    </Rec>
>    <Rec>
>       <activity>hi</activity>
>    </Rec>
> </xml>
>
> ----
>
> Above should only print anything once, but I'm getting it each time.
> What am I not getting?

Charles Knell and Scott Trenda gave advices/made notices,
thus confirming, that the problem exists. But copying the
input data and the template given by Steve and running it I
obtained exactly the result required by him in the first
topic-forming message, if I understood his request correctly.
I used MSXML (not sure about version, but don't think it's
important in this simple
case) and Saxon 9, for the latter I also tried changing
template version to 2.0 - the result stood the same. Data follows:

-----------
input.xml:
<?xml version="1.0"?>

<xml>
   <Rec>
     <activity>hi</activity>
   </Rec>
   <Rec>
      <activity>hi</activity>
   </Rec>
</xml>

-----------
input.xsl:
<?xml version="1.0"?>

<xsl:stylesheet xmlns:xsl="http://www.w3.org/1999/XSL/Transform";
version="1.0">

<xsl:template match="Rec[activity !=
preceding-sibling::Rec/activity or not(preceding-sibling::Rec)]">
  Ello xslers.
</xsl:template>

</xsl:stylesheet>

-----------
output.xml:
<?xml version="1.0" encoding="UTF-8"?>

Ello xslers.


hi


-----------

As it is clearly seen the string "Ello xslers" appears only
once and not twice as Steve wrote ("hi" comes from the defaul
copy rules, as I understand it).

Did I missed or misunderstood something very basic? Can
someone please reveal the trick to me (especially interested
in Charles' oppinion as he was involved most intensively in
the discussion).

Many thanks in advance,
Ilya

Current Thread