- Output for 7.4.0 - 7.4.33, 8.0.1 - 8.0.30, 8.1.0 - 8.1.28, 8.2.0 - 8.2.18, 8.3.0 - 8.3.6
- Fatal error: Declaration of MyClass::foo() must be compatible with NewInterface::foo(): mixed in /in/EntQu on line 13
Process exited with code 255.
<?php
interface OldInterface {
public function foo();
}
interface NewInterface {
public function foo(): mixed;
}
final class MyClass implements OldInterface, NewInterface
{
public function foo() { return null; }
}
$c = new MyClass();
$c->foo();