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

 

C++

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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)
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chrono I/O
parse (C++20)
C-style date and time

 

std::chrono::weekday

Member functions

weekday::weekday

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

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

weekday::c_encodingweekday::iso_encoding

weekday::ok

weekday::operator[]

Nonmember functions

operator==

operator+operator-

operator<<

from_stream

Helper classes

formatter<std::chrono::weekday>

formatter<std::chrono::hash> (C++26)

 

constexpr std::chrono::weekday& operator++() noexcept;	(1)	(since C++20)
constexpr std::chrono::weekday operator++( int ) noexcept;	(2)	(since C++20)
constexpr std::chrono::weekday& operator--() noexcept;	(3)	(since C++20)
constexpr std::chrono::weekday operator--( int ) noexcept;	(4)	(since C++20)

Adds or subtracts 1 from the weekday value, reducing the result modulo 7 to an integer in the range [​0​, 6].

1,2) Performs *this += std::chrono::days{1};.

3,4) Performs *this -= std::chrono::days{1};.

Parameters

(none)

Return value

1,3) A reference to this weekday after modification.

2,4) A copy of the weekday made before modification.

Notes

After a call to one of these functions, ok() is always true.

Example

Run this code

#include <cassert>
#include <chrono>
#include <iostream>
 
int main()
{
    std::cout << std::boolalpha;
 
    std::chrono::weekday wd{0}; // Sunday is 0 or 7
 
    --wd;
    std::cout << (wd == std::chrono::Saturday) << ' ';
 
    ++wd;
    std::cout << (wd == std::chrono::Sunday) << '\n';
 
    wd = std::chrono::weekday{13};
    assert(!wd.ok());
    wd++;
    assert(wd.ok());
}

Output:

true true

See also

operator+=operator-=	adds or subtracts a number of days (public member function)
operator+operator- (C++20)	performs arithmetic on weekdays (function)