I don't see any way to get a
&mut P reference to the pointer in
Pin<P>? Obviously such an operation would have to be
unsafe, but I think there's at least one valid use case for it.
Suppose you had a
Pin<Vec<T>> where T: Unpin . I think it would be safe to push to the
Vec , so long as you first check that
capacity. But you can't do this right now without first unpinning with
into_inner and then re-pinning.
In essence, I'm using
Pin<Vec<T>> as if it were
Pin<Box<[T]>> with a variable length up to a fixed capacity.
Does this make sense? Or am I missing something?