> It’s a bit complicated to set up […] it’s really fast Sigh, just use Perl. Writing code with the general regex engine took me only one minute of effort, but

> It’s a bit complicated to set up […] it’s really fast Sigh, just use Perl. Writing code with the general regex engine took me only one minute of effort, but it runs already nearly 500× faster than codeplea's optimised special purpose code. Why 100000 loops and not 10 like in the original code? Otherwise Benchmark.pm will show "(warning: too few iterations for a reliable count)". ---- benchmark.php 100000 loops: Loaded 3000 keywords to search on a text of 19377 characters. Searching with aho corasick... time: 329.3522541523 ---- benchmark.pl 100000 loops: Benchmark: timing 100000 iterations of regex... regex: 0.691561 wallclock secs ( 0.69 usr + 0.00 sys = 0.69 CPU) @ 144927.54/s (n=100000) ---- benchmark.pl (fill in the abbreviated ... parts from benchmark_setup.php): #!/usr/bin/env perl use Benchmark qw(timethese :hireswallclock); require Time::HiRes; my @needles = qw( abandonment abashed abashments abduction ... ); my $haystack = 'unscathed grampus ... heroically'; my $n = join '|', @needles; timethese 100000, { regex => sub { my @found; while ($haystack =~ /($n)/cg) { push @found, [$1, pos $haystack]; } return @found; }, index => sub { my @found; for (@needles) { my $pos = index $haystack, $_; push @found, [$_, $pos] if -1 < $pos; } return @found; } };