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run code in 300+ PHP versions simultaneously
<?php class A { private static self $singleton; public function __construct() { if(!isset(self::$singleton)) { self::$singleton = $this; } return self::$singleton; } } $a = new A; $b = new A; $c = new A; var_dump($a); var_dump($b); var_dump($c); var_dump($a->__construct());
Output for 7.4.0 - 7.4.33, 8.0.1 - 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
object(A)#1 (0) { } object(A)#2 (0) { } object(A)#3 (0) { } object(A)#1 (0) { }
preferences:
85.46 ms | 407 KiB | 5 Q