Re: [xsl] following-sibling problem

I'm still stuck on two unresolved problems.  The first is this
grouping-related one.  My problem is I end up with empty ul content
(that is invalid).  Here was my message from last week ...

One problem with the below is that I can't work out how to only add the
nested ul element if there's content.  I end up with this, for example:

         <div class="slide">
            <h2>Heading</h2>
            <ul>
               <li>Bullet 1a
                  <ul>
                     <li>B2
                        <ul></ul>
                     </li>
                  </ul>
               </li>
               <li>Bullet 1b
                  <ul>
                     <li>Bullet 2a
                        <ul></ul>
                     </li>
                     <li>Bullet 2b
                        <ul></ul>
                     </li>
                  </ul>
               </li>
            </ul>
         </div>

			<bullets>
				<bullet level="0" marker-type="inherited">
					<content>Heading</content>
				</bullet>
				<bullet level="1" marker-type="inherited">
					<content>Bullet 1a</content>
				</bullet>
				<bullet level="1" marker-type="inherited">
					<content>Bullet 1b</content>
				</bullet>
				<bullet level="2" marker-type="inherited">
					<content>Bullet 2a - a quote</content>
				</bullet>
				<bullet level="2" marker-type="inherited" id="bullet-1">
					<content>Bullet 2b</content>
				</bullet>
			</bullets>

<xsl:template match="key:bullets">
  <xsl:choose>
    <xsl:when test="../@master-slide-id='master-slide-1'">
      <xsl:apply-templates select="key:bullet[@level='0']"
mode="title"/>
    </xsl:when>
    <xsl:otherwise>
      <h2><xsl:value-of select="key:bullet[@level='0']"/></h2>
      <ul>
        <xsl:call-template name="process-level">
          <xsl:with-param name="bullet" select="key:bullet"/>
          <xsl:with-param name="level" select="1"/>
        </xsl:call-template>
      </ul>
    </xsl:otherwise>
  </xsl:choose>
</xsl:template>

<xsl:template name="process-level">
  <xsl:param name="bullet" required="yes" as="element()*"/>
  <xsl:param name="level" required="yes" as="xs:integer"/>
  <xsl:for-each-group select="$bullet[not(@level='0')]"
                group-starting-with="*[xs:integer(@level) eq $level]">
      <li><xsl:value-of select="normalize-space(.)"/>
        <ul>
          <xsl:call-template name="process-level">
            <xsl:with-param name="bullet" select="current-group()
except ."/>
            <xsl:with-param name="level" select="$level + 1"/>
          </xsl:call-template>
        </ul>
      </li>
  </xsl:for-each-group>
</xsl:template>