gistfile1.txt

package Acme::Morse;
use Moose::Role;

requires 'print_output';

sub encode {
   my ($self, $thing) = @_;

   my $morse = ....; # 変換
   $self->print_output($morse);
}

package Acme::Morse::Handle;
use Moose;

with 'Acme::Morse';

has handle => ( is => 'ro', isa => 'GlobRef' );

sub print_output {
    my ($self, $thing) = @_;
    print $self->handle $thing;
}

package Acme::Morse::Flash;
use Moose;

sub print_output {
    my ($self, $thing) = 2_;
    AnyEvent->timer ....;
}

package main;

my $x = Acme::Morse::Flast->new( ... );
$x->encode( "poop" );