3v4l.org

run code in 300+ PHP versions simultaneously
<?php abstract class T { static public $instanses; final private function __construct(){ } public static function getInstance() { if (!(static::$instanses instanceof static)) { static::$instanses = new static; } return static::$instanses; } } class A extends T { } class B extends A { } $t = A::getInstance(); var_dump($t); $t1 = B::getInstance(); var_dump($t1); ?>
Output for 5.4.0 - 5.4.45, 5.5.0 - 5.5.38, 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 - 8.1.28, 8.2.0 - 8.2.18, 8.3.0 - 8.3.6
object(A)#1 (0) { } object(B)#2 (0) { }
preferences:
248.32 ms | 404 KiB | 373 Q