Re: Count previous-siblings w/same attribute value up

If you actually want to do something with the groups at each level, then it is best to use XSLT 2:

t:\ftemp>type lou.xml
<flatOutline>
 <item numDisplay="I." level="1" />
 <item numDisplay="II." level="1" />
  <item numDisplay="A." level="2" />
  <item numDisplay="B." level="2" />
  <item numDisplay="C." level="2" />
 <item numDisplay="III." level="1"/>
  <item numDisplay="A." level="2"/>
   <item numDisplay="1." level="3" />
   <item numDisplay="2." level="3" />
   <item numDisplay="3." level="3" />
   <item numDisplay="4." level="3" />
  <item numDisplay="B." level="2"/>
   <item numDisplay="1." level="3" />
   <item numDisplay="2." level="3" />
   <item numDisplay="3." level="3" />
  <item numDisplay="C." level="2"/>
</flatOutline>

t:\ftemp>xslt2 lou.xml lou2.xsl
<?xml version="1.0" encoding="UTF-8"?>
<section level="1">
   <item numDisplay="I." level="1">1</item>
</section>
<section level="1">
   <item numDisplay="II." level="1">2</item>
   <section level="2">
      <item numDisplay="A." level="2">1</item>
      <item numDisplay="B." level="2">2</item>
      <item numDisplay="C." level="2">3</item>
   </section>
</section>
<section level="1">
   <item numDisplay="III." level="1">3</item>
   <section level="2">
      <item numDisplay="A." level="2">1</item>
      <section level="3">
         <item numDisplay="1." level="3">1</item>
         <item numDisplay="2." level="3">2</item>
         <item numDisplay="3." level="3">3</item>
         <item numDisplay="4." level="3">4</item>
      </section>
   </section>
   <section level="2">
      <item numDisplay="B." level="2">2</item>
      <section level="3">
         <item numDisplay="1." level="3">1</item>
         <item numDisplay="2." level="3">2</item>
         <item numDisplay="3." level="3">3</item>
      </section>
   </section>
   <section level="2">
      <item numDisplay="C." level="2">3</item>
   </section>
</section>
t:\ftemp>type lou2.xsl
<?xml version="1.0" encoding="UTF-8"?>
<xsl:stylesheet xmlns:xsl="http://www.w3.org/1999/XSL/Transform"
  version="2.0">
<xsl:output indent="yes"/>

<xsl:template match="/" name="do-next-group">
  <xsl:param name="group" select="/*/item"/>
  <xsl:param name="level" select="1"/>
  <xsl:choose>
    <xsl:when test="$group[@level!=$level]">
      <!--then more splitting of the group is necessary-->
      <xsl:for-each-group select="$group"
                          group-starting-with="item[@level=$level]">
        <xsl:variable name="this-position" select="position()"/>
        <section level="{$level}">
          <!--put the current level into this section-->
          <xsl:for-each select="current-group()[@level=$level]">
            <xsl:copy>
              <xsl:copy-of select="@*"/>
              <xsl:value-of select="$this-position"/>
            </xsl:copy>
          </xsl:for-each>
          <!--only nest when this group has members from deeper levels-->
          <xsl:if test="current-group()[@level!=$level]">
            <xsl:call-template name="do-next-group">
              <xsl:with-param name="group"
                              select="current-group()[@level!=$level]"/>
              <xsl:with-param name="level" select="$level+1"/>
            </xsl:call-template>
          </xsl:if>
        </section>
      </xsl:for-each-group>
    </xsl:when>
    <xsl:otherwise>
      <!--no more splitting of the group is necessary-->
      <section level="{$level}">
        <xsl:for-each select="$group">
          <xsl:copy>
            <xsl:copy-of select="@*"/>
            <xsl:value-of select="position()"/>
          </xsl:copy>
        </xsl:for-each>
      </section>
    </xsl:otherwise>
  </xsl:choose>
</xsl:template>

</xsl:stylesheet>
t:\ftemp>

--
Contact us for world-wide XML consulting and instructor-led training
Free 5-hour video lecture: XSLT/XPath 1.0 & 2.0 http://ude.my/t37DVX
Crane Softwrights Ltd.            http://www.CraneSoftwrights.com/s/
G. Ken Holman                   mailto:gkholman@xxxxxxxxxxxxxxxxxxxx
Google+ profile: https://plus.google.com/116832879756988317389/about
Legal business disclaimers:    http://www.CraneSoftwrights.com/legal