#include "tensorstore/util/small_bit_set.h"
template <typename T, typename U>
  requires (!std::is_const_v<T>) && (!std::is_const_v<U>)
void tensorstore::swap(BitRef<T> a, BitRef<U> b);

Swaps the contents of the bit to which a refers with the contents of the bit to which b refers (does not rebind a or b).