3v4l.org

run code in 300+ PHP versions simultaneously
<?php class Tools { public static $notify; public function test() { var_dump(self::$notify, (boolean)self::$notify, !self::$notify); } } $debug = true; if ($debug) { Tools::$notify = false; } $tools = new Tools; $tools->test();
Output for 7.0.0 - 7.0.20, 7.1.0 - 7.1.20, 7.2.6 - 7.2.33, 7.3.16 - 7.3.33, 7.4.0 - 7.4.33, 8.0.0 - 8.0.30, 8.1.0 - 8.1.27, 8.2.0 - 8.2.17, 8.3.0 - 8.3.4
bool(false) bool(false) bool(true)

preferences:
151.87 ms | 403 KiB | 167 Q