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run code in 300+ PHP versions simultaneously
<?php class MyClass { public function __construct($id) { if (isset(self::$cache[$id])) return self::$cache[$id]; // Do expensive setup self::$cache[$id] = $this; } private static $cache = array(); } $a = new MyClass(1);
Output for 5.5.0 - 5.5.38, 5.6.0 - 5.6.38, 7.0.0 - 7.0.32, 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
preferences:
253.15 ms | 404 KiB | 321 Q