I've implemented a custom PinVec, which is a Vec with pinned element. I'm trying to figure out if the following get/set interface is sounded.

struct PinVec<T> { ... }

impl<T> PinVec<T> {
  fn get(&self, idx: usize) -> Pin<&T> { .. }
  fn get_mut(&mut self, idx: usize) -> Pin<&mut T> { .. }
  fn push(&mut self, val: T) { .. }

  fn set(&mut self, idx: usize, val: T) { .. }
  fn remove_last(&mut self) { .. }
}

Particularly, are set and remove_last sound, do they require T: Unpin or unsafe? The relevant part seems to be this Drop Guarantee section std::pin - Rust. Though I don't know if that reads as I can drop old values safely and T will handle notifications by itself.

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