#!/usr/bin/env perl

use strict;
use warnings;

my %capture;

BEGIN {
    my $RXone   = qr{(?x: 1 )};
    my $RXthree = qr{(?x: 3 )};
    my $RXnum   = qr{(?x: $RXone | $RXthree )};
    my $RXstr   = qr{(?x: ( [a-z]+ $RXnum ) )};

    %capture = (
        menu   => {
            regexp => qr{(?x: ^ menu   \s+ $RXstr $ )},
            action => sub { parse_menu(@_) },
        },
        driver => {
            regexp => qr{(?x: ^ driver \s+ $RXstr $ )},
            action => sub { parse_driver(@_) },
        },
    );
}

my @capture_keys = keys %capture;

while (<DATA>) {
    for my $capture_key (@capture_keys) {
        if (/$capture{$capture_key}{regexp}/) {
            $capture{$capture_key}{action}->($1);
            last;
        } 
    }
}

sub parse_menu   { print "MENU:   @_\n" }
sub parse_driver { print "DRIVER: @_\n" }

__DATA__
menu menu1
driver driver1
other other1
menu menu2
driver driver2
other other2
menu menu3
driver driver3
other other3

##</code><code>##

MENU:   menu1
DRIVER: driver1
MENU:   menu3
DRIVER: driver3