http://www.perlmonks.org?node_id=46830


in reply to Re: Re: Re: Craftier
in thread Craftier

Ah, right, the original goal was not to remove all whitespace, but to compress whitespace. Here's a new benchmark:
#!perl use Benchmark; my $junk = ' The quick brown fox Jumped over the lazy dog '; timethese(-10, { 'split' => sub { $x = join ' ', split ' ', $junk; }, 'trans' => sub { ($x = $junk) =~ tr/ \t\r\n/ /s; $x =~ s/^ //; $x =~ s/ $//; }, 'subst' => sub { ($x = $junk) =~ s/\s+/ /g; $x =~ s/^ //; $x =~ s/ $//; }, 'subst2' => sub { ($x = $junk) =~ s/^\s+//; $x =~ s/\s+$//; $x =~ s/\s+/ /g; }, });
And the results:
Benchmark: running split, subst, subst2, trans, each for at least 10 CPU seconds... split: 41225.50/s subst: 40796.61/s subst2: 38222.28/s trans: 72880.42/s
split fares much better when the task is to compress whitespace, beating either substitution solution, but translate is still the winner. The extra substitutions to remove whitespace at the beginning and the end of the string slow down quite a bit the solutions which require them.