3v4l.org

run code in 300+ PHP versions simultaneously
<?php interface A { function foo(): X; } interface B extends A { function foo(): X; } $x = new class() implements A{ function foo(): X{} }; interface X { function bar(): A; } interface Y extends X { function bar(): A; }
Output for 7.1.0 - 7.1.20, 7.2.0 - 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

preferences:
88.84 ms | 407 KiB | 5 Q