MainLoop: while ($packet = getpacket())
{
    if ($packet == RESPONSE_PACKET)
    {
        deal_with_response();
    }
    else
    {
        dispatch_packet();
    }
}

sub dispatch_packet
{
    my $packet = shift;
    if ($packet == NORMAL_PACKET)
    {
        ordinary_handler();
    }
    elsif ($packet == SPECIAL_PACKET)
    {
        special_handler();
    }
}

sub ordinary_handler
{
    whatever();
}

sub special_handler
{
    ask_for_info();
    # save the state so that we can deal
    # with the response later
    save_state();
}

sub deal_with_response
{
    # get the saved state and deal with the response
    load_state();
    talk_to_the_hand();
}

__END__
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