RE: [xsl] ancestor

[Wendell Piez <wapiez@xxxxxxxxxxxxxxxx>]

Peiyun,

At 02:40 PM 10/18/2004, you wrote:
> >Has this test returned a value for you?
> ><xsl:if test="$inlineequation/@id=./@id"><xsl:value-of
> >select="position()" /></xsl:if>
> Yes, I got the one I needed.
>
> >you want to compare its value to the value of the current elements id
> attribute
> >which would look like this:
> ><xsl:if test="$inlineequation/@id = current()/@id">
> ><xsl:value-of select="position()" />
> ></xsl:if>
> Yes, you are right.
>
> More generally, I'm trying to get the position of an element in a selected
> list of elements. All elements are identifiable by   @id. If the element is
> not selected (even if it matches the element name) in the list, then nothing
> is output. I need the position of that element a few times in a matching
> template for that element in different places.

If you can describe exactly the elements whose positions you want in a 
match pattern, I think the easiest way to get what you want is probably to 
use xsl:number:

<xsl:template match="inlineequation" mode="number">
  <xsl:number count="inlineequation[not(ancestor::table)]" level="any"/>
  <!-- any formatting you want always to appear with your number, can
       go in this template too -->
<xsl:template>

<xsl:template match="inlineequation[not(ancestor::table)]">
  <xsl:apply-templates select="." mode="number"/>
  ... do your other stuff ...
</xsl:template>

This is much simpler than the approach you are currently trying. It might 
or might not perform better, depending on the processor (xsl:number can 
sometimes be slow). Other contingencies will affect this: for example, if I 
were outputting all the equations together, the gathering and counting by 
position would be more attractive. If, however, I had to reach in and find 
the correct node to number from my bunch, I'd try this method first.

Note also that if you can't use a pattern to distinguish just the nodes you 
want, you have to use the more complex approach. (We saw that a couple of 
days ago with numbering tables and figures in order of first reference to 
them....)

Cheers,
Wendell


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Wendell Piez                            mailto:wapiez@xxxxxxxxxxxxxxxx
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