Ignoring 'A' and 'The' when sorting with XSLT

Question

I would like to have a list sorted ignoring any initial definite/indefinite articles \'the\' and \'a\'. For instance:

• The Comedy of Errors
• Hamlet

Answer 1

This transformation:

<xsl:template match="plays">
 <p>Plays sorted by title: </p>
    <xsl:for-each select="play">
      <xsl:sort select=
      "concat(@title
               [not(starts-with(.,'A ') 
                  or 
                   starts-with(.,'The '))],
              substring-after(@title[starts-with(., 'The ')], 'The '),
              substring-after(@title[starts-with(., 'A ')], 'A ')
              )
     "/>
      <p>
        <xsl:value-of select="@title"/>
      </p>
    </xsl:for-each>
</xsl:template>

when applied on this XML document:

produces the wanted, correct result:

<p>Plays sorted by title: </p>
<p>Barber</p>
<p>The Comedy of Errors</p>
<p>CTA &amp; Fred</p>
<p>Hamlet</p>
<p>A Midsummer Night's Dream</p>
<p>Twelfth Night</p>
<p>The Winter's Tale</p>

Answer 2

Here is how I would do that:

<xsl:template match="plays">
    <xsl:for-each select="play">
      <xsl:sort select="substring(title, 1 + 2*starts-with(title, 'A ') + 4*starts-with(title, 'The '))"/>
      <p>
        <xsl:value-of select="title"/>
      </p>
    </xsl:for-each>
</xsl:template>

Update: I forgot to add 1 to the expression (classic off-by-one error)

Well, starts-with is from XSLT 1.0. Prooflink: the first search result in Google yields XSLT 1.0: function starts-with