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run code in 300+ PHP versions simultaneously
<?php class Singleton { private static $instance = null; private function __construct() { } public static function getInstance() { if (self::$instance === null) { self::$instance = new self(); } return self::$instance; } } $singleton = Singleton::getInstance();
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

preferences:
291.98 ms | 404 KiB | 373 Q