Would your union works for objects? 
my @unique = union{ $_[0]->isSameNode } 
                [ qw( list of xml nodes ) ], 
                [ qw( other list of xml nodes ) ] 
                #unique node list

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Edited by castaway - added code tags

In reply to Re^2: Let's unite sets by songahji
in thread Let's unite sets by songahji

Title:
Use:  <p> text here (a paragraph) </p>
and:  <code> code here </code>
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