#! /usr/bin/perl
use warnings;
use strict;

use Benchmark qw{ cmpthese };
use Test::More;

print $], "\n";
open my $W, '<', '/var/lib/dict/words' or die;
my @words = <$W>;
close $W;
my $s = '(.)(.)(.)\3\2\1';
my $re = qr/$s/;
my $tab = {
   re  => eval qq<sub { grep /$s/, \@words }>,
   qr  =>         sub { grep /$re/, @words },
   qro =>         sub { grep /$re/o, @words },
   s   =>         sub { grep /$s/, @words },
   so  =>         sub { grep /$s/o, @words },
};

my $n = $tab->{re}->();
is $tab->{$_}->(), $n, $_ for qw( qr qro s so );
done_testing();

cmpthese(-5, $tab);