$|=1;
use XML::Rules;
$xml = <<'*END*';
<school>
<classes name="Primary">
<student name="Junkman">
<Age>12</Age>
</student>
<student name="Lotman">
<Age>14</Age>
</student>
</classes>
<classes name="Nursery">
<student name="Testman">
<Age>34</Age>
</student>
</classes>
<classes name="SomeClass">
</classes>
</school>
*END*
my $parser = new XML::Rules (
rules => [
_default => '',
'^classes' => sub {return ($_[1]->{name} eq $_[4]->{parameters})}, # skip all classes whose names are not Primary
student => sub {print $_[1]->{name}."\n";}
]);
my $result = $parser->parsestring($xml, "Primary");