#!/usr/bin/perl

use strict;
use warnings;


use Animal;

my $dog = Animal->new();
$dog->type("Dog");

my $cat = Animal->new();
$cat->type("Cat");

print $dog->speak;
print $cat->speak;

-------------------------------------------------------------------
package Animal;
use Cat;
use Dog;
@ISA = qw(Cat Dog);
use strict;


sub new {
        my $proto = shift;
        my $class = ref($proto) || $proto;
        my $self  = {};
        $self->{TYPE}   = undef;
        bless ($self, $class);
        return $self;
}

sub type {
        my $self = shift;
        if (@_) { $self->{TYPE} = shift }
        return $self->{TYPE};
}

sub speak {
        my $self = shift;
        my $type = $self->{TYPE};
        $self->$type::talk;
}

1;
-------------------------------------------------------------------
package Cat;
use strict;


sub speak {
        print "meow...\n";
}


1;
-------------------------------------------------------------------
package Dog;
use strict;


sub speak {
        print "woof...\n";
}


1;