26 Time library [time]

26.8 The civil calendar [time.cal]

26.8.18 Conventional syntax operators [time.cal.operators]

A set of overloaded operator/ functions provides a conventional syntax for the creation of civil calendar dates.
[Note
:
The year, month, and day are accepted in any of the following 3 orders:
year/month/day
month/day/year
day/month/year
Anywhere a day is required, any of the following can also be specified:
last
weekday[i]
weekday[last]
end note
]
[Note
:
Partial-date types such as year_­month and month_­day can be created by not applying the second division operator for any of the three orders.
For example:
year_month ym = 2015y/April;
month_day md1 = April/4;
month_day md2 = 4d/April;
end note
]
[Example
:
auto a = 2015/4/4;         // a == int(125)
auto b = 2015y/4/4;        // b == year_­month_­day{year(2015), month(4), day(4)}
auto c = 2015y/4d/April;   // error: no viable operator/ for first /
auto d = 2015/April/4;     // error: no viable operator/ for first /
end example
]
constexpr year_month operator/(const year& y, const month& m) noexcept;
Returns: {y, m}.
constexpr year_month operator/(const year& y, int m) noexcept;
Returns: y / month(m).
constexpr month_day operator/(const month& m, const day& d) noexcept;
Returns: {m, d}.
constexpr month_day operator/(const month& m, int d) noexcept;
Returns: m / day(d).
constexpr month_day operator/(int m, const day& d) noexcept;
Returns: month(m) / d.
constexpr month_day operator/(const day& d, const month& m) noexcept;
Returns: m / d.
constexpr month_day operator/(const day& d, int m) noexcept;
Returns: month(m) / d.
constexpr month_day_last operator/(const month& m, last_spec) noexcept;
Returns: month_­day_­last{m}.
constexpr month_day_last operator/(int m, last_spec) noexcept;
Returns: month(m) / last.
constexpr month_day_last operator/(last_spec, const month& m) noexcept;
Returns: m / last.
constexpr month_day_last operator/(last_spec, int m) noexcept;
Returns: month(m) / last.
constexpr month_weekday operator/(const month& m, const weekday_indexed& wdi) noexcept;
Returns: {m, wdi}.
constexpr month_weekday operator/(int m, const weekday_indexed& wdi) noexcept;
Returns: month(m) / wdi.
constexpr month_weekday operator/(const weekday_indexed& wdi, const month& m) noexcept;
Returns: m / wdi.
constexpr month_weekday operator/(const weekday_indexed& wdi, int m) noexcept;
Returns: month(m) / wdi.
constexpr month_weekday_last operator/(const month& m, const weekday_last& wdl) noexcept;
Returns: {m, wdl}.
constexpr month_weekday_last operator/(int m, const weekday_last& wdl) noexcept;
Returns: month(m) / wdl.
constexpr month_weekday_last operator/(const weekday_last& wdl, const month& m) noexcept;
Returns: m / wdl.
constexpr month_weekday_last operator/(const weekday_last& wdl, int m) noexcept;
Returns: month(m) / wdl.
constexpr year_month_day operator/(const year_month& ym, const day& d) noexcept;
Returns: {ym.year(), ym.month(), d}.
constexpr year_month_day operator/(const year_month& ym, int d) noexcept;
Returns: ym / day(d).
constexpr year_month_day operator/(const year& y, const month_day& md) noexcept;
Returns: y / md.month() / md.day().
constexpr year_month_day operator/(int y, const month_day& md) noexcept;
Returns: year(y) / md.
constexpr year_month_day operator/(const month_day& md, const year& y) noexcept;
Returns: y / md.
constexpr year_month_day operator/(const month_day& md, int y) noexcept;
Returns: year(y) / md.
constexpr year_month_day_last operator/(const year_month& ym, last_spec) noexcept;
Returns: {ym.year(), month_­day_­last{ym.month()}}.
constexpr year_month_day_last operator/(const year& y, const month_day_last& mdl) noexcept;
Returns: {y, mdl}.
constexpr year_month_day_last operator/(int y, const month_day_last& mdl) noexcept;
Returns: year(y) / mdl.
constexpr year_month_day_last operator/(const month_day_last& mdl, const year& y) noexcept;
Returns: y / mdl.
constexpr year_month_day_last operator/(const month_day_last& mdl, int y) noexcept;
Returns: year(y) / mdl.
constexpr year_month_weekday operator/(const year_month& ym, const weekday_indexed& wdi) noexcept;
Returns: {ym.year(), ym.month(), wdi}.
constexpr year_month_weekday operator/(const year& y, const month_weekday& mwd) noexcept;
Returns: {y, mwd.month(), mwd.weekday_­indexed()}.
constexpr year_month_weekday operator/(int y, const month_weekday& mwd) noexcept;
Returns: year(y) / mwd.
constexpr year_month_weekday operator/(const month_weekday& mwd, const year& y) noexcept;
Returns: y / mwd.
constexpr year_month_weekday operator/(const month_weekday& mwd, int y) noexcept;
Returns: year(y) / mwd.
constexpr year_month_weekday_last operator/(const year_month& ym, const weekday_last& wdl) noexcept;
Returns: {ym.year(), ym.month(), wdl}.
constexpr year_month_weekday_last operator/(const year& y, const month_weekday_last& mwdl) noexcept;
Returns: {y, mwdl.month(), mwdl.weekday_­last()}.
constexpr year_month_weekday_last operator/(int y, const month_weekday_last& mwdl) noexcept;
Returns: year(y) / mwdl.
constexpr year_month_weekday_last operator/(const month_weekday_last& mwdl, const year& y) noexcept;
Returns: y / mwdl.
constexpr year_month_weekday_last operator/(const month_weekday_last& mwdl, int y) noexcept;
Returns: year(y) / mwdl.