std::chrono::weekday_indexed

 

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std::chrono::weekday_indexed

Member functions

weekday_indexed::weekday_indexed

weekday_indexed::weekday

weekday_indexed::index

weekday_indexed::ok

Nonmember functions

operator==

operator<<

Helper classes

formatter<std::chrono::weekday_indexed>

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

 

Defined in header <chrono>
class weekday_indexed;		(since C++20)

The class weekday_indexed combines a weekday, representing a day of the week in the proleptic Gregorian calendar, with a small index n in the range [1, 5]. It represents the first, second, third, fourth, or fifth weekday of some month.

weekday_indexed is a TriviallyCopyable StandardLayoutType.

Member functions

(constructor)	constructs a weekday_indexed (public member function)
weekday	access the stored weekday (public member function)
index	access the stored index (public member function)
ok	checks if the weekday and index are both valid (public member function)

Nonmember functions

operator== (C++20)	compares two weekday_indexed values (function)
operator<< (C++20)	outputs a weekday_indexed into a stream (function template)

Helper classes

std::formatter<std::chrono::weekday_indexed> (C++20)	formatting support for weekday_indexed (class template specialization)
std::hash<std::chrono::weekday_indexed> (C++26)	hash support for std::chrono::weekday_indexed (class template specialization)

Example

Run this code

#include <chrono>
#include <iostream>
 
int main()
{
    using namespace std::chrono;
 
    constexpr weekday_indexed wi = Friday[2];
 
    // Indexed weekday can be used at any place where chrono::day can be used:
    constexpr year_month_weekday ymwd = 2021y / August / wi;
    static_assert(ymwd == August / wi / 2021y &&
                  ymwd == wi / August / 2021y);
    std::cout << ymwd << '\n';
 
    constexpr year_month_day ymd{ymwd}; // a conversion
    static_assert(ymd == 2021y / 8 / 13);
    std::cout << ymd << '\n';
}

Possible output:

2021/Aug/Fri[2]
2021-08-13