> How can I convert <em>s to <i>s, such that "nested" <em>s are either 
> italic or not italic as appropriate?  That is, I want
> 
>    <em>This is <em>emphasised</em>!</em>
> 
> to be converted into
> 
>    <i>This is </i>emphasised<i>!</i>

This is perhaps not the most beautiful solution, but it might spark a few ideas:

<xsl:template match="em/text()">
  <xsl:choose>
    <xsl:when test="count(ancestor::em) mod 2 = 1">
      <em>
        <xsl:copy/>
      </em>
    </xsl:when>
    <xsl:otherwise>
      <xsl:copy/>
    </xsl:otherwise>
  </xsl:choose>
</xsl:template>



// Magnus

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