This implementation grows indefinitely if you repeatedly push to the head and remove from the tail, even if the max number of elements in the array is small
I feel like they're over-selling it anyway by comparing to `std::deque` (which is not hard to beat). The only advantage this has over a standard ring buffer (like Rust's VecDeque) is that the data is completely contiguous, but you'll pay a small performance cost for that (regular memmove's when used as a queue), and I'm not sure how useful it is anyway.