active class Base[t]
  var v  : t

  def init(v : t) : unit
    this.v = v
  end

  def base() : t
    this.v
  end
end

active class Foo
  def foo[sharable ty](arg : Fut[ty]) : ty
    get(arg ~~> fun(x : ty) : ty => get((new Base[ty](x)) ! base()))
  end
end

active class Main
  def main() : unit
    val arg = (new Base[int](42)) ! base()
    println("{}", get((new Foo) ! foo[int](arg)))
  end
end