In the following video www.youtube.com/watch you can watch a preview about this technology.
which include among all other regular syntax and rule of programing language new approach for static typing vs dynamic typing. which enable you to have them both in your program.
In the video they explain way you may need static typing.
I know there is a big argue around this but i think this video is worth seeing, since this technology is being developed from the guys who developed V8 engine.