3v4l.org

run code in 300+ PHP versions simultaneously
<?php class A { public function __invoke() { return "hello"; } } $a = new A; var_dump(is_callable($a)); function my_echo(callable $a) { echo $a() . PHP_EOL; var_dump($a instanceof A); } my_echo($a);
Output for 5.6.0 - 5.6.40, 7.0.0 - 7.0.33, 7.1.0 - 7.1.33, 7.2.0 - 7.2.33, 7.3.0 - 7.3.33, 7.4.0 - 7.4.33, 8.0.0 - 8.0.30, 8.1.0 - 8.1.34, 8.2.0 - 8.2.30, 8.3.0 - 8.3.30, 8.4.1 - 8.4.18, 8.5.0 - 8.5.3
bool(true) hello bool(true)

preferences:
99.84 ms | 1940 KiB | 4 Q