#! /usr/bin/perl
# vim:ts=4 sw=4 sts=4 et nu fdc=3:
use strict;
use warnings;

use Benchmark qw( cmpthese );

my $date1 = '2010-08-24';   # 
my $date2 = '2009-13-22';   # invalid date, but who cares


#> sub routines
#> ----------------------------------------------------------------------------

sub strcmp1 {
    my ($d1,$d2,$p,$l) = @_;
    substr($d1,$p,$l) ne substr($d2,$p,$l)
}


#> main script
#> ----------------------------------------------------------------------------

cmpthese( -1, {
    direct => sub { substr($date1,5,5) ne substr($date2,5,5) },
    regex  => sub { ($date1=~/^.....(.{5})/)[0] ne ($date2=~/^.....(.{5})/)[0] },
    sub1   => sub { strcmp1($date1,$date2,5,5) },
});

__END__