3v4l.org

run code in 300+ PHP versions simultaneously
<?php namespace { function &call_user_func_array_userland($callable, array $args) { return $callable(...$args); } } namespace Bar { $foo = 'foo'; $bar = &call_user_func_array_userland(function &() use (&$foo) { return $foo; }, []); $bar = 'bar'; echo $foo . PHP_EOL; }
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 - 8.1.33, 8.2.0 - 8.2.29, 8.3.0 - 8.3.25, 8.4.1 - 8.4.12
bar

preferences:
154.59 ms | 407 KiB | 5 Q