Online PHP editor | output for pTdMg

<?php class Banana {} class Football {} abstract class Point { abstract public function add(Point $other); abstract public function subtract(Point $other); } class Vector2 extends Point { public function add(Point|Banana $other) { if (!$other instanceof Banana) { throw new TypeError("Point only allowed to prevent compiler errors"); } // ...rest of the function } public function subtract(Point|Football $other) { if (!$other instanceof Football) { throw new TypeError("Point only allowed to prevent compiler errors"); } // ...rest of the function } } (new Vector2())->subtract( new Football() );