Re: comparing nodesets to each other

without seeing what your source xml looks like, or what output format
you want to generate it's fairly impossible to give any specific advice,
but a few observations.

      <xsl:variable name="variation">
   ...

this means that $variation will hole a result tree fragment, which means
that

      <xsl:for-each select="$variation">

will generate an error on a conformant XSLT 1.0  processor, if you are
using XSLT 2, best to say so, as any answeres are likely to be rather
different in that case. For XSLT1 you'd need a node-set extension
function.


In general it's rather hard to define "difference" (see a long thread on
exactly that subject lastweek)

for example if your two fragments are

<a>
 <b/>
 <c/>
 <d/>
</a>

and

<a>
 <x/>
 <b/>
 <c/>
 <d/>
</a>

What do you want to mark as the "difference", is it that an element x
was added (this does actually correspond to the edit I made to generate
the text above) or do you want to mark that the frst child changed from
b to x, the second from c to b, the third from d to c, and a new fourth
child, d added.

Depending on which of those two answers you want, the code is likely to
be radically different. 



         <xsl:if test=". != $compare-node">
            <xsl:copy-of select="."/>
            <xsl:attribute name="different">current</xsl:attribute>
         </xsl:if>

This will always generate an error if teh test is true.
The copy-of . copies an element node, and then xsl:attribute tries to
add an attribute to the currently open node, ie the parent of teh node
just copied, and you can not add attributes to an element once a child
has been added.

David

________________________________________________________________________
This e-mail has been scanned for all viruses by Star. The
service is powered by MessageLabs. For more information on a proactive
anti-virus service working around the clock, around the globe, visit:
http://www.star.net.uk
________________________________________________________________________