3v4l.org

run code in 300+ PHP versions simultaneously
<?php function test1() { $s = microtime(true); $var = null; for ($i = 0; $i < 1000000; $i++) { $condition = $var === null; } return microtime(true) - $s; } function test2() { $s = microtime(true); $var = null; for ($i = 0; $i < 1000000; $i++) { $condition = !isset($var); } return microtime(true) - $s; } echo test1() . "\n\n"; echo test2() . "\n\n";

preferences:
30.68 ms | 402 KiB | 5 Q