Simple (?) Singleton Question

[rwilkerson]

Not being a seasoned PHP developer, tonight I started playing with the use of the Singleton pattern to store configuration information.  What I was surprised to find was that the instance - at least the one I'm creating - isn't really a singleton.  With each request, the constructor is called.  Isn't that very much *not* a singleton or am I misunderstanding or doing something wrong?  I'm using a pretty simple case:

 

class Config
{
    private static $instance;

    private function __construct() { 
		echo '<p>Constructing</p>';
}

    public static function getInstance()
    {
        if (!self::$instance)
        {
            self::$instance = new self();
        }

        return self::$instance;
    }
    public function clear() { 
	echo '<p>clearing...</p>';
	self::$instance    = null; 
    }
}

 

What am I not doing or not understanding?

 

Any insight would be greatly appreciated.

 

Rob

[btherl]

Please provide your test code as well.