gistfile1.pl

#!/usr/bin/perl

package Bang;

sub new { bless {}, __PACKAGE__ }

package main;

use AnyEvent;

BEGIN {
  require AnyEvent::IRC::Client;
  *AnyEvent::IRC::Client::DESTROY = sub { warn "bai from AE::IRC" };
  *Bang::DESTROY = sub { warn "bai from Bang" };
}

my $cl = AnyEvent::IRC::Client->new;
undef $cl;

my $b = Bang->new;
undef $b;

AE::cv->recv;