オブジェクトの例(3/4)

package Music::Media::CD;
use Jukebox;
@ISA = qw(Music::Media);  # 継承

sub play {
    my $self = shift;
    my $number = $self->{number};
    Jukebox->bynumber($number)->play;
}

package Music::Media::MP3;
use MP3;
@ISA = qw(Music::Media);
sub play {
    my $self = shift;
    for (@{$self->{contents}}) {
        MP3::play($_->[2]);
        sleep(2);
    }
}