#!/usr/local/bin/perl use strict; use Benchmark; my $string = "<;nbsp dont_strip_me> ;strip_me"; sub reversed { my $reverse = reverse(shift); $reverse =~ s| \w* ; \s* > |>|x; return scalar reverse $reverse; } sub greedy { my $line = shift; $line =~ s|^ (.*>) \s* ; \w* |$1|x; return $line; } sub capture { my $line = shift; return $line =~ /^(.+>)/; } print "Reversed: ", reversed($string), "\n"; print "Greedy: ", greedy($string), "\n"; print "Capture: ", capture($string), "\n"; timethese( -10,{ reversed => sub { reversed( $string ) }, greedy => sub { greedy( $string ) }, capture => sub { capture( $string ) }, } ); #### :!./test.pl Reversed: <;nbsp dont_strip_me> Greedy: <;nbsp dont_strip_me> Capture: <;nbsp dont_strip_me> Benchmark: running capture, greedy, reversed, each for at least 10 CPU seconds... capture: 10 wallclock secs (10.40 usr + 0.01 sys = 10.41 CPU) @ 53160.52/s (n=553401) greedy: 10 wallclock secs (10.52 usr + 0.00 sys = 10.52 CPU) @ 21887.07/s (n=230252) reversed: 11 wallclock secs (10.54 usr + 0.01 sys = 10.55 CPU) @ 36366.92/s (n=383671)