std::chrono::operator/ (calendar)

 

C++

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Standard library headers

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Feature test macros (C++20)

Language support library

Concepts library (C++20)

Metaprogramming library (C++11)

Diagnostics library

General utilities library

Strings library

Containers library

Iterators library

Ranges library (C++20)

Algorithms library

Numerics library

Localizations library

Input/output library

Filesystem library (C++17)

Regular expressions library (C++11)

Concurrency support library (C++11)

Technical specifications

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External libraries

 

Utilities library

Language support Type support (basic types, RTTI) Library feature-test macros (C++20) Dynamic memory management Program utilities Coroutine support (C++20) Variadic functions is_constant_evaluated (C++20) launder (C++17) initializer_list (C++11) source_location (C++20) Three-way comparison (C++20) three_way_comparablethree_way_comparable_with (C++20)(C++20) strong_ordering (C++20) weak_ordering (C++20) partial_ordering (C++20) common_comparison_category (C++20) compare_three_way_result (C++20) compare_three_way (C++20) strong_order (C++20) weak_order (C++20) partial_order (C++20) compare_strong_order_fallback (C++20) compare_weak_order_fallback (C++20) compare_partial_order_fallback (C++20)    is_eqis_neqis_ltis_lteqis_gtis_gteq (C++20)(C++20)(C++20)(C++20)(C++20)(C++20)

General utilities Date and time Function objects Formatting library (C++20) bitset hash (C++11) Relational operators (deprecated in C++20) rel_ops::operator!=rel_ops::operator> rel_ops::operator<=rel_ops::operator>= Integer comparison functions cmp_equalcmp_lesscmp_less_than (C++20)(C++20)(C++20)    cmp_not_equalcmp_greatercmp_greater_than (C++20)(C++20)(C++20) in_range (C++20) Swap and type operations swap ranges::swap (C++20) exchange (C++14) declval (C++11) to_underlying (C++23) forward (C++11) forward_like (C++23) move (C++11) move_if_noexcept (C++11) as_const (C++17) Common vocabulary types pair tuple (C++11) optional (C++17) any (C++17) variant (C++17) tuple_size (C++11) tuple_element (C++11) apply (C++17) make_from_tuple (C++17) expected (C++23) Elementary string conversions to_chars (C++17) from_chars (C++17) chars_format (C++17)

 

Date and time utilities

Time point
time_point (C++11)	clock_time_conversion (C++20)	clock_cast (C++20)
Duration
duration (C++11)
Clocks
system_clock (C++11) steady_clock (C++11) high_resolution_clock (C++11)	is_clock (C++20) utc_clock (C++20) tai_clock (C++20)	gps_clock (C++20) file_clock (C++20) local_t (C++20)
Time of day
is_amis_pm (C++20)(C++20)	make12make24 (C++20)(C++20)	hh_mm_ss (C++20)
Calendars
day (C++20) month (C++20) year (C++20) weekday (C++20) operator/ (C++20) year_month_day (C++20)	year_month_day_last (C++20) year_month_weekday (C++20) year_month_weekday_last (C++20)       weekday_indexed (C++20) weekday_last (C++20) month_day (C++20)	month_day_last (C++20) month_weekday (C++20) month_weekday_last (C++20) year_month (C++20) last_speclast (C++20)(C++20)
Time zones
tzdb (C++20) tzdb_list (C++20) get_tzdbget_tzdb_listreload_tzdbremote_version (C++20)(C++20)(C++20)(C++20) sys_info (C++20)	local_info (C++20) nonexistent_local_time (C++20) ambiguous_local_time (C++20) locate_zone (C++20) current_zone (C++20) time_zone (C++20) choose (C++20)	zoned_traits (C++20) zoned_time (C++20) time_zone_link (C++20) leap_second (C++20) leap_second_info (C++20) get_leap_second_info (C++20)
chrono I/O
parse (C++20)
C-style date and time

 

Defined in header <chrono>
year_month
constexpr auto operator/( const std::chrono::year& y,                           const std::chrono::month& m ) noexcept     -> std::chrono::year_month;	(1)	(since C++20)
constexpr auto operator/( const std::chrono::year& y, int m ) noexcept     -> std::chrono::year_month;	(2)	(since C++20)
month_day
constexpr auto operator/( const std::chrono::month& m,                           const std::chrono::day& d ) noexcept     -> std::chrono::month_day;	(3)	(since C++20)
constexpr auto operator/( const std::chrono::month& m, int d ) noexcept     -> std::chrono::month_day;	(4)	(since C++20)
constexpr auto operator/( int m, const std::chrono::day& d ) noexcept     -> std::chrono::month_day;	(5)	(since C++20)
constexpr auto operator/( const std::chrono::day& d,                           const std::chrono::month& m ) noexcept    -> std::chrono::month_day;	(6)	(since C++20)
constexpr auto operator/( const std::chrono::day& d, int m ) noexcept     -> std::chrono::month_day;	(7)	(since C++20)
month_day_last
constexpr auto operator/( const std::chrono::month& m,                          std::chrono::last_spec ) noexcept     -> std::chrono::month_day_last;	(8)	(since C++20)
constexpr auto operator/( int m, std::chrono::last_spec ) noexcept     -> std::chrono::month_day_last;	(9)	(since C++20)
constexpr auto operator/( std::chrono::last_spec,                           const std::chrono::month& m ) noexcept     -> std::chrono::month_day_last;	(10)	(since C++20)
constexpr auto operator/( std::chrono::last_spec, int m ) noexcept     -> std::chrono::month_day_last;	(11)	(since C++20)
month_weekday
constexpr auto operator/( const std::chrono::month& m,                           const std::chrono::weekday_indexed& wdi ) noexcept     -> std::chrono::month_weekday;	(12)	(since C++20)
constexpr auto operator/( int m, const std::chrono::weekday_indexed& wdi ) noexcept     -> std::chrono::month_weekday;	(13)	(since C++20)
constexpr auto operator/( const std::chrono::weekday_indexed& wdi,                           const std::chrono::month& m ) noexcept     -> std::chrono::month_weekday;	(14)	(since C++20)
constexpr auto operator/( const std::chrono::weekday_indexed& wdi, int m ) noexcept     -> std::chrono::month_weekday;	(15)	(since C++20)
month_weekday_last
constexpr auto operator/( const std::chrono::month& m,                           const std::chrono::weekday_last& wdl ) noexcept     -> std::chrono::month_weekday_last;	(16)	(since C++20)
constexpr auto operator/( int m, const std::chrono::weekday_last& wdl ) noexcept     -> std::chrono::month_weekday_last;	(17)	(since C++20)
constexpr auto operator/( const std::chrono::weekday_last& wdl,                           const std::chrono::month& m ) noexcept     -> std::chrono::month_weekday_last;	(18)	(since C++20)
constexpr auto operator/( const std::chrono::weekday_last& wdl, int m ) noexcept     -> std::chrono::month_weekday_last;	(19)	(since C++20)
year_month_day
constexpr auto operator/( const std::chrono::year_month& ym,                           const std::chrono::day& d ) noexcept     -> std::chrono::year_month_day;	(20)	(since C++20)
constexpr auto operator/( const std::chrono::year_month& ym, int d ) noexcept     -> std::chrono::year_month_day;	(21)	(since C++20)
constexpr auto operator/( const std::chrono::year& y,                           const std::chrono::month_day& md ) noexcept     -> std::chrono::year_month_day;	(22)	(since C++20)
constexpr auto operator/( int y, const std::chrono::month_day& md ) noexcept     -> std::chrono::year_month_day;	(23)	(since C++20)
constexpr auto operator/( const std::chrono::month_day& md,                           const std::chrono::year& y ) noexcept     -> std::chrono::year_month_day;	(24)	(since C++20)
constexpr auto operator/( const std::chrono::month_day& md, int y ) noexcept     -> std::chrono::year_month_day;	(25)	(since C++20)
year_month_day_last
constexpr auto operator/( const std::chrono::year_month& ym,                          std::chrono::last_spec ) noexcept     -> std::chrono::year_month_day_last;	(26)	(since C++20)
constexpr auto operator/( const std::chrono::year& y,                           const std::chrono::month_day_last& mdl ) noexcept     -> std::chrono::year_month_day_last;	(27)	(since C++20)
constexpr auto operator/( int y, const std::chrono::month_day_last& mdl ) noexcept     -> std::chrono::year_month_day_last;	(28)	(since C++20)
constexpr auto operator/( const std::chrono::month_day_last& mdl,                           const std::chrono::year& y ) noexcept     -> std::chrono::year_month_day_last;	(29)	(since C++20)
constexpr auto operator/( const std::chrono::month_day_last& mdl, int y ) noexcept     -> std::chrono::year_month_day_last;	(30)	(since C++20)
year_month_weekday
constexpr auto operator/( const std::chrono::year_month& ym,                           const std::chrono::weekday_indexed& wdi ) noexcept     -> std::chrono::year_month_weekday;	(31)	(since C++20)
constexpr auto operator/( const std::chrono::year& y,                           const std::chrono::month_weekday& mwd ) noexcept     -> std::chrono::year_month_weekday;	(32)	(since C++20)
constexpr auto operator/( int y, const std::chrono::month_weekday& mwd ) noexcept     -> std::chrono::year_month_weekday;	(33)	(since C++20)
constexpr auto operator/( const std::chrono::month_weekday& mwd,                           const std::chrono::year& y ) noexcept     -> std::chrono::year_month_weekday;	(34)	(since C++20)
constexpr auto operator/( const std::chrono::month_weekday& mwd, int y ) noexcept     -> std::chrono::year_month_weekday;	(35)	(since C++20)
year_month_weekday_last
constexpr auto operator/( const std::chrono::year_month& ym,                           const std::chrono::weekday_last& wdl ) noexcept     -> std::chrono::year_month_weekday_last;	(36)	(since C++20)
constexpr auto operator/( const std::chrono::year& y,                           const std::chrono::month_weekday_last& mwdl ) noexcept     -> std::chrono::year_month_weekday_last;	(37)	(since C++20)
constexpr auto operator/( int y, const std::chrono::month_weekday_last& mwdl ) noexcept     -> std::chrono::year_month_weekday_last;	(38)	(since C++20)
constexpr auto operator/( const std::chrono::month_weekday_last& mwdl,                           const std::chrono::year& y ) noexcept     -> std::chrono::year_month_weekday_last;	(39)	(since C++20)
constexpr auto operator/( const std::chrono::month_weekday_last& mwdl, int y ) noexcept     -> std::chrono::year_month_weekday_last;	(40)	(since C++20)

These operator/ overloads provide a conventional syntax for the creation of Gregorian calendar dates.

For creation of a full date, any of the following three orders are accepted:

• year/month/day
• month/day/year
• day/month/year.

In each case day can replaced with one of:

• std::chrono::last, for the last day of the month;
• weekday[i], for the i-th weekday of the month;
• weekday[std::chrono::last], for the last weekday of the month.

A plain integer is accepted if its meaning is unambiguous from the types of other operands: 2005y/4/5 is allowed, but 5/April/2005 is not.

Partial-date types (year_month, month_day, etc.) can be created by not applying the second operator/ in any of the three orders.

Return value

1) std::chrono::year_month(y, m)

2) std::chrono::year_month(y, std::chrono::month(m))

3,6) std::chrono::month_day(m, d)

4) std::chrono::month_day(m, std::chrono::day(d))

5,7) std::chrono::month_day(std::chrono::month(m), d)

8,10) std::chrono::month_day_last(m)

9,11) std::chrono::month_day_last(std::chrono::month(m))

12,14) std::chrono::month_weekday(m, wdi)

13,15) std::chrono::month_weekday(std::chrono::month(m), wdi)

16,18) std::chrono::month_weekday_last(m, wdl)

17,19) std::chrono::month_weekday_last(std::chrono::month(m), wdl)

20) std::chrono::year_month_day(ym.year(), ym.month(), d)

21) std::chrono::year_month_day(ym.year(), ym.month(), std::chrono::day(d))

22,24) std::chrono::year_month_day(y, md.month(), md.day())

23,25) std::chrono::year_month_day(std::chrono::year(y), md.month(), md.day())

26) std::chrono::year_month_day_last(ym.year(), std::chrono::month_day_last(ym.month()))

27,29) std::chrono::year_month_day_last(y, mdl)

28,30) std::chrono::year_month_day_last(std::chrono::year(y), mdl)

31) std::chrono::year_month_weekday(ym.year(), ym.month(), wdi)

32,34) std::chrono::year_month_weekday(y, mwd.month(), mwd.weekday_indexed())

33,35) std::chrono::year_month_weekday(std::chrono::year(y), mwd.month(), mwd.weekday_indexed())

36) std::chrono::year_month_weekday_last(ym.year(), ym.month(), wdl)

37,39) std::chrono::year_month_weekday_last(y, mwdl.month(), mwdl.weekday_last())

38,40) std::chrono::year_month_weekday_last(std::chrono::year(y), mwdl.month(), mwdl.weekday_last())

Example

Run this code

#include <iostream>
#include <chrono>
using namespace std::chrono;
 
int main()
{
    std::cout << std::boolalpha;
 
    // standard provides 2021y as option for std::chrono::year(2021)
    // standard provides 15d as option for std::chrono::day(15)
 
    constexpr auto ym {year(2021)/8};
    std::cout << (ym == year_month(year(2021), August)) << ' ';
 
    constexpr auto md {9/day(15)};
    std::cout << (md == month_day(September, day(15))) << ' ';
 
    constexpr auto mdl {October/last};
    std::cout << (mdl == month_day_last(month(10))) << ' ';
 
    constexpr auto mw {11/Monday[3]};
    std::cout << (mw == month_weekday(November, Monday[3])) << ' ';
 
    constexpr auto mwdl {December/Sunday[last]};
    std::cout << (mwdl == month_weekday_last(month(12), weekday_last(Sunday))) << ' ';
 
    // Those three year/month/day orders that people actually use on this planet:
    constexpr auto ymd {year(2021)/January/day(23)};
    static_assert(ymd == month{1}/23/2021);
    static_assert(ymd == day{23}/1/2021);
    std::cout << (ymd == year_month_day(2021y, month(January), 23d)) << '\n';
}

Output:

true true true true true true