Another way would be to make the subroutine curried (that is expecting to get the parameters separately, not all at once): 

foreach my $file (@files){
# set up the XML parser:
 my $twig= XML::Twig->new( 
  twig_handlers => { topicref => topicref_processing($file),
               xref => topicref_processing($file) },
 );
 $twig->parsefile($file);
 $twig->purge;
}

sub topicref_processing {
  my ($file) = @_;
  return sub {
    my($twig, $topicref) = @_;
    my($atts) = $topicref->atts();
    if($$atts{'keyref'}){
     ### associate this keyref with $file
    }
  }
}

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Jenda
Enoch was right!
Enjoy the last years of Rome.

In reply to Re^2: XML::Twig newbie question by Jenda
in thread XML::Twig newbie question by slugger415

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