Общение между двумя классами Singletone

[goldlider]

Собственно не могу понять, в чем ошибка. Компилятор показывает на строчку throw new Error("Game is a singletone class");

package
{
	import flash.display.Sprite;
 
	public class Game extends Sprite
	{
		private static var _allowInstantiation:Boolean = true;
		private static var _instance:Game;
 
		private var _hud:HUD;
 
		public static function get instance():Game
		{
			if (!_instance)
			{
				_allowInstantiation = false;
				_instance = new Game();
				_allowInstantiation = true;
			}
 
			return _instance;
		}
 
		public function Game()
		{
			if (_allowInstantiation)
			{
				throw new Error("Game is a singletone class");
			}
			initialize();
		}
 
		private function initialize():void
		{
			_hud = HUD.instance;
			addChild(_hud);
		}
	}
}

package
{
	import flash.display.Sprite;
 
	public class HUD extends Sprite
	{
		private static var _allowInstantiation:Boolean = true;
		private static var _instance:HUD;
 
		private var _game:Game;
 
		public static function get instance():HUD
		{
			if (!_instance)
			{
				_allowInstantiation = false;
				_instance = new HUD();
				_allowInstantiation = true;
			}
 
			return _instance;
		}
 
		public function HUD()
		{
			if (_allowInstantiation)
			{
				throw new Error("HUD is a singletone class");
			}
			initialize();
		}
 
		private function initialize():void
		{
			_game = Game.instance;
		}
	}
}