3v4l.org

run code in 300+ PHP versions simultaneously
<?php class Foo { public function __construct() { echo "Side effect!\n"; } } const C = new Foo();
Output for 8.1.0 - 8.1.6
Side effect!
Output for 7.4.0 - 7.4.29, 8.0.1 - 8.0.19
Fatal error: Constant expression contains invalid operations in /in/MSWi0 on line 9
Process exited with code 255.

preferences:
29.53 ms | 410 KiB | 5 Q