това е най-бавния вариант:

#!/usr/bin/perl



use strict;

use Benchmark qw(:all);



$main::string = 'aaaaaaaaaa';

$main::buffer = 'a';

$main::same   = 1;

@main::array_full = split '', $main::string;

@main::array_part = qw(a b a a a a a a a a);



my $result = timethese(10_000_000, {

        'equal_full' => '$main::buffer eq $_ or last for @main::array_full;',

        'equal_part' => '$main::buffer eq $_ or last for @main::array_part;',

        'regex'      => '$main::string =~ /^\Q$main::buffer\E+$/o',

        'substr'     => 'for (0..length($main::string)) {

                                if (substr($main::string,$_,1) ne $main::buffer) {

                                        $main::same=0;

                                        last;

                                }

                        }',

});



cmpthese( $result );



__END__



stdout:



Benchmark: timing 10000000 iterations of equal_full, equal_part, regex, substr...

equal_full: 38 wallclock secs (30.03 usr +  0.04 sys = 30.07 CPU) @ 332557.37/s (n=10000000)

equal_part: 13 wallclock secs ( 8.79 usr +  0.00 sys =  8.79 CPU) @ 1137656.43/s (n=10000000)

     regex:  9 wallclock secs ( 7.81 usr +  0.01 sys =  7.82 CPU) @ 1278772.38/s (n=10000000)

    substr: 72 wallclock secs (51.92 usr +  0.05 sys = 51.97 CPU) @ 192418.70/s (n=10000000)

                Rate     substr equal_full equal_part      regex

substr      192419/s         --       -42%       -83%       -85%

equal_full  332557/s        73%         --       -71%       -74%

equal_part 1137656/s       491%       242%         --       -11%

regex      1278772/s       565%       285%        12%         --