std::chrono::operator+, std::chrono::operator- (std::chrono::weekday)

 

C++

Language

Standard Library Headers

Freestanding and hosted implementations

Named requirements

Language support library

Concepts library (C++20)

Diagnostics library

Utilities library

Strings library

Containers library

Iterators library

Ranges library (C++20)

Algorithms library

Numerics library

Input/output library

Localizations library

Regular expressions library (C++11)

Atomic operations library (C++11)

Thread support library (C++11)

Filesystem library (C++17)

Technical Specifications

 

Utilities library

Type support (basic types, RTTI, type traits)
Dynamic memory management
Error handling
Program utilities
Variadic functions
Library feature-test macros
Date and time
Function objects
initializer_list (C++11)
bitset
hash (C++11)
integer_sequence (C++14)
Relational operators (deprecated in C++20)
rel_ops::operator!=rel_ops::operator>rel_ops::operator<=rel_ops::operator>=
Comparisons (C++20)
strong_order weak_order partial_order strong_equal weak_equal	strong_ordering weak_ordering partial_ordering strong_equality weak_equality	is_eqis_neqis_ltis_lteqis_gtis_gteq
common_comparison_category
Common vocabulary types
pair tuple (C++11) apply (C++17) make_from_tuple (C++17)	optional (C++17) any (C++17) variant (C++17)
Swap, forward and move
swap
exchange (C++14)
forward (C++11)
move (C++11)
move_if_noexcept (C++11)
Elementary string conversions
to_chars (C++17)
from_chars (C++17)
chars_format (C++17)
Type operations
declval (C++11)
as_const (C++17)
launder (C++17)

 

Date and time utilities

duration (C++11) time_point (C++11) time_of_day (C++20)	clock_time_conversion (C++20) clock_cast (C++20)
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)
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)
Time zones
tzdb (C++20) tzdb_list (C++20) get_tzdbget_tzdb_listreload_tzdbremote_version (C++20)(C++20)(C++20)(C++20)	time_zone (C++20) locate_zone (C++20) current_zone (C++20) zoned_time (C++20) link (C++20) leap (C++20)
C-style date and time

 

std::chrono::weekday

Member functions

weekday::weekday

weekday::operator++weekday::operator--

weekday::operator+=weekday::operator-=

weekday::operator unsigned

weekday::ok

weekday::operator[]

Nonmember functions

operator==operator!=

operator+operator-

operator<<

to_stream

from_stream

 

constexpr std::chrono::weekday operator+(const std::chrono::weekday& wd,                                          const std::chrono::days& d) noexcept;	(1)	(since C++20)
constexpr std::chrono::weekday operator+(const std::chrono::days& d,                                          const std::chrono::weekday& wd) noexcept;	(2)	(since C++20)
constexpr std::chrono::weekday operator-(const std::chrono::weekday& wd,                                          const std::chrono::days& d) noexcept;	(3)	(since C++20)
constexpr std::chrono::days operator-(const std::chrono::weekday& wd1,                                       const std::chrono::weekday& wd2) noexcept;	(4)	(since C++20)

1-2) Adds d.count() days to wd. The weekday value held in the result is computed by first evaluating static_cast<long long>(unsigned(wd)) + d.count() and reducing it modulo 7 to an integer in the range [0, 6].

3) Subtracts d.count() days from wd. Equivalent to return wd + -d;

4) If wd1.ok() and wd2.ok() are both true, returns a std::chrono::days value d such that d.count() is in the range [0, 6] and wd2 + d == wd1. Otherwise the returned value is unspecified.

Return value

1-3) A std::chrono::weekday holding a weekday value calculated as described above.

4) A std::chrono::days representing the distance between wd1 and wd2.

Notes

As long as the computation doesn't overflow, (1-3) always return a valid weekday even if wd.ok() is false.

See also

operator++operator++(int)operator--operator--(int)	increments or decrements the weekday (public member function)
operator+=operator-=	adds or subtracts a number of days (public member function)