Online PHP editor | output for CfuF7

<?php interface MultitonInterface { public static function getInstance(string $key); } trait MultitonTrait { private static array $instance = []; public static function getInstance(string $key): self { if (!array_key_exists($key, self::$instance)) { self::$instance[$key] = new self; } return self::$instance[$key]; } } class Database implements MultitonInterface { use MultitonTrait; private function __construct(){} private function __clone(){} public function __wakeup(){} public function connect() { echo "..."; } } $db = Database::getInstance('mysql'); $db->connect();