sub fib_no_log { my @fibonacci = (0, 1); my ($n, $sum) = (1, 0); while ($n < 1_000_000) { $n = $fibonacci[$#fibonacci] + $fibonacci[ $#fibonacci - 1 ]; push @fibonacci, $n; $sum += $n if (($n % 2) == 0); } return $sum; } ... 'fib_no_log' => sub { fib_no_log() },