Benchmarking Regexp vs. Grep vs. Hash for "finding"

reggrephash.pl

#!/usr/bin/env perl

use Benchmark qw( cmpthese );

my %in = (
        bar => 1,
        baz => 1,
        foo => 1,
);

my %out = (
        bar => 1,
        baz => 1,
        boo => 1,
);

cmpthese(
    10_000_000,
    { 'Grep' => sub {
            grep { $_ eq 'foo' } qw(bar baz foo);
        },
        '!Grep' => sub {
            grep { $_ eq 'foo' } qw(bar baz boo);
        },
        'Regexp' => sub { 'foo' =~ m/bar|baz|foo/ },
        '!Regexp' => sub { 'foo' =~ m/bar|baz|boo/ },
        'Hash' => sub { defined $in{foo} },
        '!Hash' => sub { defined $out{foo} },
    }
);


__END__

             Rate  Regexp    Grep   !Grep    Hash !Regexp   !Hash
Regexp   181192/s      --    -69%    -70%    -91%    -91%    -93%
Grep     583771/s    222%      --     -4%    -72%    -73%    -79%
!Grep    609756/s    237%      4%      --    -71%    -71%    -78%
Hash    2114165/s   1067%    262%    247%      --     -0%    -23%
!Regexp 2123142/s   1072%    264%    248%      0%      --    -22%
!Hash   2732240/s   1408%    368%    348%     29%     29%      --