gistfile1.php

<?php
# Bench functional programming
$start = microtime(true);
$fact = function($x, $y = 1) use (&$fact) {
  if ($x == 0) {
		return $y;
	}
	return $fact($x - 1, $y * $x);
};
$fact(30000) . "\n";
echo (microtime(true) - $start) * 1000 . "\n";

# Bench traditionnal programming
$start = microtime(true);
function recurv($x, $y = 1) {
	if ($x == 0) {
		return 1;
	}
	return recurv($x - 1, $x * $y);
}
recurv(30000) . "\n";
echo (microtime(true) - $start) * 1000 . "\n";