23 General utilities library [utilities]

23.17 Time utilities [time]

23.17.5 Class template duration [time.duration]

23.17.5.6 duration comparisons [time.duration.comparisons]

In the function descriptions that follow, CT represents common_­type_­t<A, B>, where A and B are the types of the two arguments to the function.
template<class Rep1, class Period1, class Rep2, class Period2> constexpr bool operator==(const duration<Rep1, Period1>& lhs, const duration<Rep2, Period2>& rhs);
Returns: CT(lhs).count() == CT(rhs).count().
template<class Rep1, class Period1, class Rep2, class Period2> constexpr bool operator!=(const duration<Rep1, Period1>& lhs, const duration<Rep2, Period2>& rhs);
Returns: !(lhs == rhs).
template<class Rep1, class Period1, class Rep2, class Period2> constexpr bool operator<(const duration<Rep1, Period1>& lhs, const duration<Rep2, Period2>& rhs);
Returns: CT(lhs).count() < CT(rhs).count().
template<class Rep1, class Period1, class Rep2, class Period2> constexpr bool operator<=(const duration<Rep1, Period1>& lhs, const duration<Rep2, Period2>& rhs);
Returns: !(rhs < lhs).
template<class Rep1, class Period1, class Rep2, class Period2> constexpr bool operator>(const duration<Rep1, Period1>& lhs, const duration<Rep2, Period2>& rhs);
Returns: rhs < lhs.
template<class Rep1, class Period1, class Rep2, class Period2> constexpr bool operator>=(const duration<Rep1, Period1>& lhs, const duration<Rep2, Period2>& rhs);
Returns: !(lhs < rhs).