{
	package Person;
	
	use Moo;
	
	has name     => (is => 'ro', required => 1);
	has age      => (is => 'rw', required => 1);
	
	sub introduce_yourself {
		my $self = shift;
		printf("My name is %s, and I am %d years old.\n", $self->name, $self->age);
	}
}

{
	package Breeding;
	
	use Moo::Role;
	
	has children => (is => 'ro', default => sub { return []; });
	
	sub is_parent {
		my $self = shift;
		@{ $self->children };
	}
	
	sub bear_children {
		my $self = shift;
		my ($partner, @kids_names) = @_;
		
		for my $name (@kids_names) {
			my $kid = ref($self)->new(name => $name, age => 0);
			push @{ $self->children }, $kid;
			push @{ $partner->children }, $kid;
		}
		
		return;
	}
}

{
	package Person::Breeding;
	
	use Moo;
	extends 'Person';
	with 'Breeding';
}


my $alice = Person::Breeding->new(name => 'Alice', age => 32);
my $bob   = Person::Breeding->new(name => 'Bob', age => 31);

$_->introduce_yourself for $alice, $bob;

$alice->bear_children($bob, 'Carol', 'Dave', 'Eve');

print "Bob is a father!\n" if $bob->is_parent;