my $mb = Mail::MboxParser->new('some_mailbox', decode => 'ALL');

    # -----------
    
    # slurping
    for my $msg ($mb->get_messages) {
        print $msg->header->{subject}, "\n";
        $msg->store_all_attachments('/tmp');
    }

    # iterating
    while (my $msg = $mb->next_message) {
        print $msg->header->{subject}, "\n";
        # ...
    }