`Rc` implies ownership, albeit shared one. So if a heap location is held by `Rc`, all reference to it should be either `Rc` or `Weak`. You can't have an `Rc` an

`Rc` implies ownership, albeit shared one. So if a heap location is held by `Rc`, all reference to it should be either `Rc` or `Weak`. You can't have an `Rc` and a `Box` for the same data, IIUC. A `Box` is unaware of `Rc` and will drop its data when dropped itself.