mp_units::inverse

template<
    Unit auto To,
    auto R,
    typename Rep>
[[nodiscard]]
constexpr
Quantity auto
inverse(quantity<R, Rep> const& q)
requires (!detail::scaling_overflows_non_zero_values<Rep>(one / get_unit®, To)) && requires {
    representation_values<Rep>::one();
    value_cast<To>(representation_values<Rep>::one() / q);
  };