use strict;
use Benchmark qw(cmpthese);

cmpthese (-10, {
   a => 's/\s*#.*//',
   b => '$_ = $` if /#/',
   c => 'my ($line) = split/#/',
   d => '$_ = substr($_, 0, $-[0]) if /#/',
   e => 'if ((my $p = index($_, "#")) > -1) { substr($_, $p, -1, "") }'
});