A general <xsl:key> question.

My XSL (1.0) reference doesn't have any reference to the <xsl:key> and
the <xsl:key> FAQ I've reviewed provides some examples and answers
specific questions, it does not provide a general overview.  I'm been
entirely unsucessful in accessing the nodes I'm trying to associated
with the key.

Do keys have to be used within a context in which the associated nodes
exist?

During my XLS processing a create a set of nodes (which I change to a
node-set).  This set of nodes could be viewed as a set of indexes or
keys.  My primary processing involving looping through this set of
constructed nodes.  For each node I then process a subset of nodes
loaded from the XML file; this set of nodes are not children or siblings
of the constructed nodes.

This is where I am attempting to apply the key construct, but it appears
to always return a empty node list.  Maybe my key generation logic is
flawed, but unless I'm really confused, at worst case I might always get
a key of '1'.  I've included pieces of the original XSL; there's too
much to provide a complete context.
 

<!--
# Template which triggers processing for all rows associated with a
PageNode.
#
# CONTEXT: PageNode
-->
<!--**PATCH**-->
<xsl:key name="PageKey" match="/gnsl:Results/gnsl:Table/gnsl:Row"
         use="((count(preceding-sibling::*) div $RowsPerPage) + 1)" />
<!--**PATCH**-->

<xsl:template name="ProcessPageRows">
   <xsl:variable name="PageNum" select="@PageNum" />
   <xsl:variable name="StartRow" select="@StartRow" />
   <xsl:variable name="EndRow" select="@EndRow" />

   <xsl:if test="$NumberOfRows">
      <!--**PATCH**
       xsl:for-each select="$AllInputRows[ (position() &gt;= $StartRow)
and
                                           (position() &lt;= $EndRow) ]"
      **PATCH**-->
      <xsl:for-each select="key('PageKey',$PageNum)">
         <xsl:apply-templates select="." />
      </xsl:for-each>
   </xsl:if>
</xsl:template>


-- 
Edward L. Knoll   Phone (work)     : (719)484-2717
                  e-mail (work)    : ed.knoll@xxxxxxxxxxxxxx
                  e-mail (business): eknoll@xxxxxxxxxx
                  e-mail (personal): edward@xxxxxxxxxxx

 XSL-List info and archive:  http://www.mulberrytech.com/xsl/xsl-list