When to call www.Dispose() and assetBundle.Unload() ?

Unity Engine
1

I was wondering what the proper Unity way of calling Dispose and assetBundle.Unload were?

If I Instantiate a gameObject using assetBundle.Load() and then Destroy it later do I have to keep references to the original www.assetBundle and the www class to call Dispose and Unload after Destroy(gameObject)?

Simple example below.

IEnumerable Download(string url)
{
  myDownloader = new WWW(url);
  yield return myDownloader ;

  myObj = (GameObject)Instantiate(myDownloader.assetBundle.mainAsset);

  // should Dispose be called here?
  // if it is IDisposable won't that only clear unused references?
}

void DestroyDownloadedObject(GameObject obj)
{
    Destroy(obj);
    myAssetBundle.Unload(true);
    myDownloader.Dispose();
}
   
// do I need to keep the AssetBundle and WWW reference? 
AssetBundle myAssetBundle;
WWW myDownloader;
GameObject myObj;
2

You’ll notice on the AssetBundle.Unload doc page that when its boolean parameter is set to false then assets created from the asset bundle won’t be destroyed when it is unloaded. If you set the parameter to true, then the created assets will be destroyed along with the bundle.

Once you have a reference to the AssetBundle object in your code, it shouldn’t matter what you do with the WWW object that it was downloaded with.