Re: "vertical slices" of tree

[Johannes Lebek]

The following script prints the names of the nodes that belong to these 
"vertical slices":

<?xml version="1.0"?>
<xsl:stylesheet version="1.0" 
xmlns:xsl="http://www.w3.org/1999/XSL/Transform";>
  <xsl:output method="text"/>
  <xsl:template match="/">
    <xsl:for-each select="node()/node()[not(name() = '')]">
      <xsl:text>'</xsl:text>
      <xsl:value-of select="name()"/>
      <xsl:text>'</xsl:text>
      <xsl:text>&#xA;</xsl:text>
    </xsl:for-each>
    <xsl:text>&#xA;</xsl:text>

    <xsl:for-each select="node()/node()/node()[not(name() = '')]">
      <xsl:text>'</xsl:text>
      <xsl:value-of select="name()"/>
      <xsl:text>'</xsl:text>
      <xsl:text>&#xA;</xsl:text>
    </xsl:for-each>
    <xsl:text>&#xA;</xsl:text>
    <xsl:for-each select="node()/node()/node()/node()[not(name() = '')]">
      <xsl:text>'</xsl:text>
      <xsl:value-of select="name()"/>
      <xsl:text>'</xsl:text>
      <xsl:text>&#xA;</xsl:text>
    </xsl:for-each>
  </xsl:template>
</xsl:stylesheet>
The output is:
'b'
'e'
'c'
'f'
'd'
'g'
Please note:
1) Predicate "[not(name() = '')]" is required to skip text nodes.
2) Retrieving names of nodes of a 'certain' depth could be achieved by
   using a recursively called template (parameter: depth)
Regards,
Johannes

Joseph Kesselman wrote:

"Siblings" was my first reaction too (the sibling axes and/or
children-of-same-parent). However, if one takes a deeper "slice", nodes at
the same depth may not actually be siblings. For example, see C and E in:
      <a>
            <b>
                  <C/>
            </b>
            <d FOO="bar">
                  <E/>
            </d>
      </a>
If that's what's intended, I'm not sure what the best XPath expression
would be. One approach is "nodes with same number of ancestors as this
one", but you'd need to think about whether the attribute FOO is considered
part of the same slice as C and E.
______________________________________
Joe Kesselman, IBM Next-Generation Web Technologies: XML, XSL and more.
"The world changed profoundly and unpredictably the day Tim Berners Lee
got bitten by a radioactive spider." -- Rafe Culpin, in r.m.filk