XSL Tips - Recursion

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Recursion
  This examples shows how you can call a template recursitively in xsl. Note that is follows the base rules for recursion:
1. It calls itself
2. At least one parameter changes
3. As a way to end
This is useful when you need to use recursion of course, but more importantly to do a loop not base on xml nodes because there is no independent of node loop functions in xsl. Remember that xsl:for-each will loop through each matching node.
XML
<?xml version="1.0" encoding="US-ASCII" ?>

<test>m</test>

XSL
<?xml version="1.0" encoding="US-ASCII" ?>
<xsl:stylesheet xmlns:xsl="http://www.w3.org/1999/XSL/Transform" version="1.0">
  <xsl:output method="html" omit-xml-declaration="no" indent="yes" />

  <xsl:template match="test">
    <xsl:call-template name="loop">
      <xsl:with-param name="var">3</xsl:with-param>
    </xsl:call-template>
  </xsl:template>

  <xsl:template name="loop">
    <xsl:choose>
      <xsl:when test="$var &gt; 0">
        test
        <xsl:call-template name="loop">
          <xsl:with-param name="var">
            <xsl:number value="number($var)-1" />
          </xsl:with-param>
        </xsl:call-template>
      </xsl:when>
      <xsl:otherwise>
        weird
      </xsl:otherwise>
    </xsl:choose>
  </xsl:template>

</xsl:stylesheet>
Result
test test test weird