<stx:transform version="1.0" 
  xmlns:stx="http://stx.sourceforge.net/2002/ns"
  strip-space="yes">

  <stx:variable name="var1" select="(1,2,3)"/>

  <stx:template match="/root">
    <root>
      <stx:variable name="var2" select="('a','b')"/>

      <stx:for-each-item name="i" select="$var1">
	<stx:variable name="var3" select="'0'"/>
	<i>
	  <stx:for-each-item name="j" select="$var2">
	    <j>
	      <stx:value-of select="concat($i,$j,$var3)"/>
	    </j>
	  </stx:for-each-item>
	</i>
      </stx:for-each-item>

    </root>
  </stx:template>


</stx:transform>