> This proposal does not include the dual facility of auto-unboxing.
> However, the expert group may choose to contemplate that facility as well,
> if its inclusion can be done in a manner that is not overly disruptive to the language as a whole.
ってあるから、まだ auto-unboxing は無いんじゃないの？Casting conversion(キャスト変換)はあるから、
キャストで明示的に unboxing するしかないと。