AS3 movieClip Path

programming flash
1

I am wondering why the AS3 movieClip target path are soo complicated? I’m loading a simple external swf that contain a movieClip that I want to play with. But I can’t find the proper syntaxe to call this movieClip… Can someone help me, please!

var swfLoader:Loader = new Loader();
holderSWF.addChild(swfLoader);
var externalSWF:URLRequest=new URLRequest(“externalFile.swf”);
swfLoader.contentLoaderInfo.addEventListener(Event.COMPLETE, loadProdComplete);
swfLoader.load(externalSWF);
function loadProdComplete(e:Event):void {
// in AS2 I would say _root.holderSWF.some_movieClip._x = 50;

// My try in AS3
// 1120: Access of undefined property loader.
var swf:MovieClip = MovieClip(loader.content);    
swf._x = 50;

}