27 Time library [time]

27.8 The civil calendar [time.cal]

27.8.15 Class year_­month_­day_­last [time.cal.ymdlast]

27.8.15.3 Non-member functions [time.cal.ymdlast.nonmembers]

constexpr bool operator==(const year_month_day_last& x, const year_month_day_last& y) noexcept;
Returns: x.year() == y.year() && x.month_­day_­last() == y.month_­day_­last().
constexpr bool operator<(const year_month_day_last& x, const year_month_day_last& y) noexcept;
Returns: If x.year() < y.year(), returns true.
Otherwise, if x.year() > y.year(), returns false.
Otherwise, returns x.month_­day_­last() < y.month_­day_­last().
constexpr year_month_day_last operator+(const year_month_day_last& ymdl, const months& dm) noexcept;
Returns: (ymdl.year() / ymdl.month() + dm) / last.
constexpr year_month_day_last operator+(const months& dm, const year_month_day_last& ymdl) noexcept;
Returns: ymdl + dm.
constexpr year_month_day_last operator-(const year_month_day_last& ymdl, const months& dm) noexcept;
Returns: ymdl + (-dm).
constexpr year_month_day_last operator+(const year_month_day_last& ymdl, const years& dy) noexcept;
Returns: {ymdl.year()+dy, ymdl.month_­day_­last()}.
constexpr year_month_day_last operator+(const years& dy, const year_month_day_last& ymdl) noexcept;
Returns: ymdl + dy.
constexpr year_month_day_last operator-(const year_month_day_last& ymdl, const years& dy) noexcept;
Returns: ymdl + (-dy).
template<class charT, class traits> basic_ostream<charT, traits>& operator<<(basic_ostream<charT, traits>& os, const year_month_day_last& ymdl);
Returns: os << ymdl.year() << '/' << ymdl.month_­day_­last().