Re: [xsl] suppressing only the last PI

[egarrett@xxxxxxxxxxxx]

Thanks for your help.  I am trying to process all nodes, though, not 
just the PIs.  It looks as if I change this, it will only grab the PIs 
that are not specified, and not the other content.  Am I interpreting 
this correctly?


----- Original Message -----
From: Abel Braaksma <abel.online@xxxxxxxxx>
Date: Wednesday, January 3, 2007 3:23 pm
Subject: Re: [xsl] suppressing only the last PI
To: xsl-list@xxxxxxxxxxxxxxxxxxxxxx

> Emily.Garrett@xxxxxxxxxxx wrote:
> > However, the following instruction occurs prior to the content and
> > should suppress only the last PI, but is suppressing all processing
> > instructions named TL_XSL and whose value beings with 'PageEnd_' 
> and not
> > just the last one:
> >
> >    <xsl:apply-templates
> > select="node()[not(self::processing-instruction('TL_XSL')[starts-
> with(.,> 'PageEnd_')][position()=last()])]"/>
> >         
> > Can anyone tell what is wrong with it and why it is not just 
> suppressing> the last one? 
> 
> Hi Emily,
> 
> Instead of not(), use position != last(). Like this:
> 
> node()[self::processing-instruction('TL_XSL')
> [starts-with(.,'PageEnd_')]][position()!=last()]
> 
> Using the function not() returns true if the so-called effective 
> boolean 
> value of the argument returns false. In your case, the instruction 
> inside the brackets is an xpath expression that always returns 
> something 
> when at a processing instruction. The reverse being false. This 
> has to 
> do with shifting the square brackets. This becomes apparent when 
> dissecting your expression:
> 
> node()
>   [not
>      (
>         self::processing-instruction('TL_XSL')
>         [starts-with(., 'PageEnd_')]
>         [position()=last()]
>      )
>   ]
> 
> Remove  not() and proc-instr() for clarity leaves:
> 
> 1)      node()[[starts-with(., 'PageEnd_')]
> 2)      [position()=last()]]
> 
> Look closely at the square brackets. It says: "In the current 
> node, select all that starts with PageEnd, and if so, select the 
> last one you find". Effectively, you select a "group of one node 
> and take its last node", which is always true (for nodes that 
> start with PageEnd that is).
> 
> Reverse that, and it is always false.
> 
> If you want to use not(), you can do so, but put the brackets in 
> the right position, and reverse only the part you want to reverse 
> (namely, the test for last()):
> 
> node()
>   [self::processing-instruction('TL_XSL')]
>   [starts-with(., 'PageEnd_')]
>   [not(position()=last())]
> 
> But I'd find it more readable using != instead of not(), but 
> that's a matter of taste.
> 
> HtH,
> 
> Cheers,
> -- Abel Braaksma
>   http://www.nuntia.nl