#!perl-w



use Benchmark qw(:all);

$toto = 'this+is+my+text';

$count =-5;


$results = timethese($count, 

            {

                'Translating' => sub { my($copy)=$toto; $copy =~tr/+/ 
+/; },

                'Substituting' => sub { my($copy)=$toto;$copy =~s/\+/ 
+/g; },

            },

            'none'

        );

        cmpthese( $results ) ;

__END__

Yielded:

                 Rate Substituting  Translating
Substituting 140156/s           --         -68%
Translating  436379/s         211%           --
[download]

Another perl function which out performs regex is index(), for checking for exact matches in textual data:

#!perl-w

use Benchmark qw(:all);

$toto = 'this+is+my+text';

$count =-5;


$results = timethese($count, 

            {

                'Indexing' => sub { my($copy)=$toto; $index = index($c
+opy, 'is');},

                'matching' => sub { my($copy)=$toto;$match if $copy =~
+/is/; },

            },

            'none'

        );

        cmpthese( $results ) ;

__END__
Gave:
             Rate matching Indexing
matching 552818/s       --     -14%
Indexing 641382/s      16%       --
[download]

but obviously there are limitations, with tr// you can't use it on only part of a string and index() only returns the position of the first match of an exact term or character in text data. The extra control and options offered by regex are what make them slower than both these functions in given situations.

Update

As Davido pointed out the original benchmark tests were flawed and have since been adjusted.