RE: [xsl] xslt node-set variable transversal

["Kyle Partridge" <kpartridge@xxxxxxxxxxxx>]

Andreas,

Thank you so much for your response!!

I know that all the preceding and following siblings of "region" will be
available from inside the template I'm calling.  But the problem is, I
ONLY want to process "region" nodes that belong within the column I'm
processing.

For example, let's say I want to turn my xml document into a PDF
document that is 439pt wide (8.5 inches).

I could easily have this, as the xml document <regions>:

<xsl:variable name="useable-page-width">493</xsl:variable>
<regions>
	<region left="36pt"..............etc
	<region left="120pt".............etc
	<region left="630pt".............etc
	<region left="230pt".............etc
</regions>

So, now, if I just do a template that matches on regions, for example,
and I get to region 4, and I want to find the space-before to draw that
region correctly on the page, if I don't re-screen all the
preceding-siblings, I'll get region 3 - which is outside of the column
I'm processing.

<xsl:template match:"ws:regions">
	<xsl:apply-templates select="ws:region[@left&gt;0 and
(@left+@width)&lt;number($useable-page-width)]"/>
</xsl:template>

<xsl:template match="ws:region">
	<!-- to get space-before for a region, I 
	need to subtract the bottom of the previous region
	from the top of this one - but I want to *ignore*
	any regions that don't belong in this space... -->

	<xsl:variable name="prev-region"
select="preceding-sibling::ws:region[@left&gt;0 and (@left+@width)&lt;
number($useable-page-width)][1]"/>
	
	<fo:block space-before={number(($prev-region/@top +
$prev-region/@height)-@top)){$units}}...............etc.

</xsl:template>

What I don't like about this is, every time I want to process a region I
have to re-filter all the nodes that don't belong in the column I care
about.  Is that the only way?

Thanks so much, again for your help.

KP

Andreas wrote:

<snip>
However, there seems to be something rather awkward about the structure

<xsl:for-each select="$nodes">
  ...
  <xsl:apply-templates select="." mode="different-mode">
    <xsl:with-param name="pprec" select="preceding-sibling::*" />
    <xsl:with-param name="pfoll" select="following-sibling::*" />
  </xsl:apply-templates>

</xsl:for-each>

which seems more or less what you're trying to do.

The reason for my thinking so is the fact that the preceding- and
following-sibling axes will *per se* be available from within the
matching
template, since the context node will be changed by the
apply-templates --I'm absolutely dazzled as to why you would want to
pass
these in as parameters...

The above just needs to become:
<xsl:apply-templates select="$nodes">
  <xsl:with-param name="pparam" select="expr" />
</xsl:apply-templates>

where the param is used to collect data which is easily accessible from
the
context surrounding the apply-templates, but won't be too easily
reachable
from within the context of the matching template.
</snip>