How to reuse once allocated space

[l4l]

I have a use case like this:

loop {
  let mut vec = boxcar::Vec::with_capacity(WELL_KNOWN_UPPER_LIMIT);

  // ..

  concurrently_append_updates(&mut vec);

  // ..

  let some_data = vec.iter().fold(..);
}

so in the end of the loop I want to reuse the memory and avoid dealloc-alloc on each iteration. Don't see anything suitable exposed in the api. Perhaps Vec::reset(self) -> Self could work?