Online PHP editor | refs for KPDDa

<?php function ref(&$array) { foreach ($array as $item) { $item; } } function notref($array) { foreach ($array as $item) { $item; } } $array = range(0, 1000); $start = microtime(true); ref($array); echo 'time: '.(microtime(true) - $start).' sec'; $start = microtime(true); notref($array); echo 'time: '.(microtime(true) - $start).' sec';