Ah well. If we're allowed to cheat then the difference moves into the realms of run to run variability :)

use strict; use warnings; use 5.010; use Benchmark qw[ cmpthese ]; use List::Util qw[ shuffle ]; our @terms = qw[ the quick brown fox jumps over the lazy dog ]; our $re = join'', map "(?=^.*$_)", @terms; #$re = qr/$re/; our @lines = map join( ' ', shuffle @terms), 1 .. 100; push @lines, ( 'every good boy deserves food' ) x 100; my $line = join '&&', map {"/$_/"} @terms; our( $a, $b, $c, $d) = (0) x 4; cmpthese -1, { a=>q[ /$re/ and ++$a for @lines; ], d=>qq[ /$re/ and ++\$d for \@lines; ], b=>q[ for my $str ( @lines ) { !grep( $str !~ /$_/, @terms) and ++ +$b; } ], c=>qq [$line && ++\$c for \@lines;], }; say "$a:$b:$c:$d"; __END__ C:\test>junk48 Rate b a d c b 82.7/s -- -97% -97% -99% a 2657/s 3112% -- -3% -56% d 2748/s 3222% 3% -- -54% c 5982/s 7132% 125% 118% -- 388200:12000:829800:389700

Examine what is said, not who speaks -- Silence betokens consent -- Love the truth but pardon error.
"Science is about questioning the status quo. Questioning authority".
In the absence of evidence, opinion is indistinguishable from prejudice.

In reply to Re^9: Regex match at the beginning or end of string by BrowserUk
in thread Regex match at the beginning or end of string by cyber-guard

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