29 Time library [time]

29.8 The civil calendar [time.cal]

29.8.16 Class year_month_weekday [time.cal.ymwd]

29.8.16.1 Overview [time.cal.ymwd.overview]

namespace std::chrono { class year_month_weekday { chrono::year y_; // exposition only chrono::month m_; // exposition only chrono::weekday_indexed wdi_; // exposition only public: year_month_weekday() = default; constexpr year_month_weekday(const chrono::year& y, const chrono::month& m, const chrono::weekday_indexed& wdi) noexcept; constexpr year_month_weekday(const sys_days& dp) noexcept; constexpr explicit year_month_weekday(const local_days& dp) noexcept; constexpr year_month_weekday& operator+=(const months& m) noexcept; constexpr year_month_weekday& operator-=(const months& m) noexcept; constexpr year_month_weekday& operator+=(const years& y) noexcept; constexpr year_month_weekday& operator-=(const years& y) noexcept; constexpr chrono::year year() const noexcept; constexpr chrono::month month() const noexcept; constexpr chrono::weekday weekday() const noexcept; constexpr unsigned index() const noexcept; constexpr chrono::weekday_indexed weekday_indexed() const noexcept; constexpr operator sys_days() const noexcept; constexpr explicit operator local_days() const noexcept; constexpr bool ok() const noexcept; }; }
year_month_weekday represents a specific year, month, and weekday of the month.
year_month_weekday is a field-based time point with a resolution of days.
[Note 1: 
year_month_weekday supports years- and months-oriented arithmetic, but not days-oriented arithmetic.
For the latter, there is a conversion to sys_days, which efficiently supports days-oriented arithmetic.
— end note]
year_month_weekday meets the Cpp17EqualityComparable (Table 28) requirements.
year_month_weekday is a trivially copyable and standard-layout class type.