gistfile1.as

package 
{
	import flash.display.Sprite;
	import flash.events.Event;
	import flash.system.System;
	import flash.utils.Dictionary;

	public class Main extends Sprite 
	{
		
		private var _test:Test;
		private var _dict:Dictionary = new Dictionary(true);
		private var _count:int = 0;
		public function Main():void 
		{
			init();
			addEventListener(Event.ENTER_FRAME, handleEnterFrame);
		}
		
		private function init():void 
		{
			_test = new Test();
			addChild(_test);
			_dict[_test] = true;
		}
		
		private function handleEnterFrame(e:Event):void {
			_count++;
			if (_count >= 10 && _test != null) {
				removeChild(_test);
				_test = null;
				System.gc();
				System.gc();
			}
			var items:int = 0;
			for (var i:* in _dict) {
				trace(i);
				items++;
			}
			trace(items);
		}
		
	}
	
}
import flash.display.Sprite;
import flash.events.Event;

class Test extends Sprite {
	
	public function Test() {
		addEventListener(Event.ENTER_FRAME, handleEnterFrame);
	}
	
	private function handleEnterFrame(e:Event):void {
		trace("Test::enterFrame");
	}
	
}