How can I group homogenous data in xsl? - xslt

Question

Let's say we have following data:
<all>
<item id="1"/>
<item id="2"/>
...
<item id="N"/>
</all>
What is the most elegant, xslt-ish way to group those items?
For example, imagine we want a table with two cells in each row.
Off the top of my head I can imagine (not tested though)
in template, matching item, I can call this very item, selecting following-sibling.
But even in this case I should pass additional param, to make recursion finite.

Answer 1

As row-count can be variable .. am passing it as a param to the template .. :)
<?xml version="1.0" encoding="utf-8"?>
<xsl:stylesheet version="1.0" xmlns:xsl="http://www.w3.org/1999/XSL/Transform">
<xsl:output method="html" indent="yes"/>
<xsl:template match="/all[node]">
<table>
<xsl:for-each select="node[1]">
<xsl:call-template name="whoaa">
<xsl:with-param name="count" select="'1'"/>
<xsl:with-param name="row_count" select="'10'"/>
<!--maximum row_count is set to 10 -->
</xsl:call-template>
</xsl:for-each>
</table>
</xsl:template>
<xsl:template name="whoaa">
<xsl:param name="count"/>
<xsl:param name="row_count"/>
<!--check if we have crossed row_count-->
<xsl:if test="not ($row_count < $count)">
<tr>
<td>
<xsl:value-of select="."/>
</td>
<td>
<!--copy next column-->
<xsl:for-each select="following-sibling::node[1]">
<xsl:value-of select="."/>
</xsl:for-each>
</td>
</tr>
<!--Select next row .. call the same template untill we reach (row_count > count)-->
<xsl:for-each select="following-sibling::node[2]">
<xsl:call-template name="whoaa">
<xsl:with-param name="count" select="$count+2"/>
<xsl:with-param name="row_count" select="$row_count"/>
</xsl:call-template>
</xsl:for-each>
</xsl:if>
</xsl:template>
</xsl:stylesheet>

Answer 2

use position and mod, e.g.
<xsl:template match="/all">
<table>
<xsl:apply-templates name="item" mode="group"/>
</table>
</xsl:template>
<xsl:template match="item[position() mod 2=1]" mode="group">
<tr>
<td><xsl:apply-templates select="." mode="render"/></td>
<td><xsl:apply-templates select="following-sibling::item[1]" mode="render"/></td>
</tr>
</xsl:template>
<xsl:template match="item[position() mod 2=0]"></xsl:template>
<xsl:template match="item" mode="render">item: <xsl:value-of select="#id"/></xsl:template>