std::chrono::day::operator+=, std::chrono::day::operator-= - cppreference.com (original) (raw)

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Date and time library

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) is_clock(C++20) utc_clock(C++20) tai_clock(C++20) high_resolution_clock(C++11) 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) Calendar 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) chrono I/O parse(C++20) Time zone 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) C-style date and time

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std::chrono::day

Member functions
day::day
day::operator++day::operator--
day::operator+=day::operator-=
day::operator unsigned
day::ok
Nonmember functions
operator==operator<=>
operator+operator-
operator<<
from_stream
[operator""d](../operator%2522%2522d.html "cpp/chrono/operator""d")
Helper classes
formatterstd::chrono::day
hashstd::chrono::day(C++26)

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constexpr std::chrono::day& operator+=( const std::chrono::days& d ) noexcept; (1) (since C++20)
constexpr std::chrono::day& operator-=( const std::chrono::days& d ) noexcept; (2) (since C++20)

Adds or subtracts d.count() days from the day value.

  1. Equivalent to *this = *this + d;.

  2. Equivalent to *this = *this - d;.

Contents

[edit] Return value

A reference to this day after modification.

[edit] Notes

If the result would be outside the range [​0​, 255], the actual stored value is unspecified.

[edit] Example

Run this code

#include #include   int main() { std::chrono::day d{15};   d += std::chrono::days(2); assert(d == std::chrono::day(17));   d -= std::chrono::days{3}; assert(d == std::chrono::day(14)); }

[edit] See also

operator++operator++(int)operator--operator--(int) increments or decrements the day (public member function) [edit]
operator+operator-(C++20) adds or subtracts a number of days and a day, or find the difference between two days (function) [edit]