3v4l.org

run code in 300+ PHP versions simultaneously
<?php class B { public function __toString() { return "Instances of B() can be treated as a strings!\n"; } } $b = new B(); print($b); //Instances of B() can be treated as a strings! print(is_string($b) ? 'true' : 'false'); //false
Output for 7.1.0 - 7.1.33, 7.2.0 - 7.2.33, 7.3.0 - 7.3.30, 7.4.0 - 7.4.23, 8.0.0 - 8.0.10, 8.1rc1 - rc2
Instances of B() can be treated as a strings! false

preferences:
46.73 ms | 459 KiB | 5 Q