Re: private/public __construct in PHP / Singleton pattern

Joe Stump wrote:

I've ran across what I feel is a bug in PHP5's OOP. I'm trying to create a singleton pattern, but PHP5 doesn't allow you to do this with base classes with public __construct() it appears. For instance: <?php abstract class A {

    public function __construct()
    {
        echo __CLASS__;
    }

} class B extends A {

    private static $instance;

    private function __construct()
    {
        parent::__construct();
    }

    public static function singleton()
    {
        if (!isset(self::$instance)) {
            $c = __CLASS__;
            self::$instance = new $c;
        }

        return self::$instance;
    }

} $b = B::singleton(); ?> Results in the following error: <br /> <b>Fatal error</b>: Access level to B::__construct() must be public (as in class A) in <b>/usr/local/httpd/htdocs/framework/foo.php</b> on line <b>29</b><br /> Am the the only one that finds this retarded? --Joe

Per the documentation, you can only open-up the declaration (say, from private to protected to public) but not the other way around. I think you could resolve that by using "protected" on the A::__construct() and "final protected" on B::__construct() That will prevent people from directly creating instances, if I get what you're trying to do. -Philippe