Grouping XML nodes using XSL 2.0

Man, that was painful!!! Curse those XML Committee morons that should have designed a transformation language based on Perl, rather than come with the atrocity that is XSL!

So, let's say you have the following XML (This is a list of cross references between 8051 banks, custom generated by a popular disassembler), which you already sorted using the other XSL I posted today:

<banks>
 <B0_000E/>
 <B0_000E/>
 <B0_000E/>
 <B0_000E/>
 <B0_49F8/>
 <B0_49F8/>
 <B0_49F8/>
 <B0_49F8/>
 <B0_49F8/>
 <B0_49F8/>
 <B0_520A/>
 <B0_520A>
    <BD_2E9D/>
    <BD_C4B5/>
 </B0_520A>
 <B0_520A/>
 <B0_54F9/>
 <B0_54F9/>
 <B0_54F9>
    <BB_E851/>
 </B0_54F9>
 <B0_54F9/>
 <B0_59EC>
    <B0_012F/>
 </B0_59EC>
 <B0_59EC>
    <BE_012F/>
 </B0_59EC>
 <B0_59EC>
    <BF_012F/>
 </B0_59EC>
 <B0_CC5E/>
 <B0_CC5E>
    <BC_DAA6/>
    <BC_DF2E/>
 </B0_CC5E>
 <B0_CC5E>
    <BB_DA1C/>
 </B0_CC5E>
 <B0_CC5E/>
  <B0_E022/>
 <B0_E022>
    <BE_E439/>
    <BE_E458/>
    <BE_EE05/>
    <BE_EE28/>
    <BE_F15B/>
    <BE_F17A/>
    <BE_F8E5/>
    <BE_F8F9/>
 </B0_E022>
 <B0_E022>
    <BF_3BF0/>
    <BF_6C6B/>
    <BF_7F7E/>
    <BF_7F9D/>
    <BF_7FE0/>
    <BF_7FFF/>
    <BF_CD2C/>
    <BF_D103/>
    <BF_D126/>
    <BF_D146/>
    <BF_D169/>
 </B0_E022>
 <B0_E022/>
 <B0_E022>
    <BC_CE5A/>
 </B0_E022>
 <B0_E022/>
 <B0_E022/>
 <B0_E201/>
 <B0_E201/>
</banks>

Obviously now, you would like to move all the sub nodes into a single one and remove all the duplicates to obtain a file like this:

<banks>
 <B0_000E/>
 <B0_49F8/>
 <B0_520A>
    <BD_2E9D/>
    <BD_C4B5/>
 </B0_520A>
 <B0_54F9>
    <BB_E851/>
 </B0_54F9>
 <B0_59EC>
    <B0_012F/>
    <BE_012F/>
    <BF_012F/>
 </B0_59EC>
 <B0_CC5E>
    <BC_DAA6/>
    <BC_DF2E/>
    <BB_DA1C/>
 </B0_CC5E>
 <B0_E022>
    <BE_E439/>
    <BE_E458/>
    <BE_EE05/>
    <BE_EE28/>
    <BE_F15B/>
    <BE_F17A/>
    <BE_F8E5/>
    <BE_F8F9/>
    <BF_3BF0/>
    <BF_6C6B/>
    <BF_7F7E/>
    <BF_7F9D/>
    <BF_7FE0/>
    <BF_7FFF/>
    <BF_CD2C/>
    <BF_D103/>
    <BF_D126/>
    <BF_D146/>
    <BF_D169/>
    <BC_CE5A/>
 </B0_E022>
 <B0_E201/>
</banks>

Well, using the XSL (2.0) below, now you can!

<xsl:stylesheet version="2.0" xmlns:xsl="http://www.w3.org/1999/XSL/Transform">
<xsl:output omit-xml-declaration="yes" indent="yes"/>

<xsl:template match="/">
  <banks> <!-- Our XML root element. Modify according to yours! -->
    <!-- Select all nodes that are immediate children of our root
         element ("/*/*") and group them according to their node
         names ("local-name()")  -->
    <xsl:for-each-group select="/*/*" group-by="local-name()">
      <!-- Output a (single) node for each of these groups -->
      <xsl:element name="{local-name()}">
      <!-- NB: To remove empty nodes, move the <xsl:element>
           section inside the <xsl:for-each-group> below, and use
           {local-name(parent::*)} instead of {local-name()} -->
        <!-- Select all the children nodes from the above group
             ("current-group()/*) - Don't bother to group them. -->
        <xsl:for-each-group select="current-group()/*" group-by=".">
          <!-- Here we copy the whole (group) branch as is -->
          <xsl:copy-of select="current-group()"/>
        </xsl:for-each-group>
      </xsl:element>
    </xsl:for-each-group>
  </banks> <!-- Close our root -->
</xsl:template>
</xsl:stylesheet>