that was silly of me
thank you for pointing it out

use strict;
use warnings;

use XML::Twig;

my $xml = <<XML;
<foo>
   <bar>
      <bay V="A" />
      <baz V="B" />
   </bar>
</foo>
XML

my $t = XML::Twig->new
(
  twig_handlers => { '/foo/bar' => sub
      { 
         my $bay = $_->first_child('bay');
         my $baz = $_->first_child('baz');

         print $bay->att("V");
         print $baz->att("V");
       }
   }
);

$t->parse ($xml);
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