3v4l.org

run code in 300+ PHP versions simultaneously
<?php class A { function __isset($x) { echo '__isset: ', $x; return rand(); } } $a = new A; echo empty($a);
Output for 5.0.0 - 5.0.5, 5.1.0 - 5.1.6, 5.2.0 - 5.2.17, 5.3.0 - 5.3.29, 5.4.0 - 5.4.45, 5.5.0 - 5.5.36, 5.6.0 - 5.6.28, 7.0.0 - 7.0.20, 7.1.0 - 7.1.33, 7.2.17 - 7.2.25, 7.3.0 - 7.3.12, 7.4.0
Output for 4.3.0 - 4.3.11, 4.4.0 - 4.4.9
1

preferences:
189.23 ms | 401 KiB | 238 Q