std::chrono::year_month_weekday::year_month_weekday
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                    < cpp | chrono | year month weekday
                    
                                                            
                    |   year_month_weekday() = default;  | 
(1) | (since C++20) | 
|   constexpr year_month_weekday(const std::chrono::year& y, const std::chrono::month& m, const std::chrono::weekday_indexed& wdi) noexcept;  | 
(2) | (since C++20) | 
|   constexpr year_month_weekday(const std::chrono::sys_days& dp) noexcept;  | 
(3) | (since C++20) | 
|   explicit constexpr year_month_weekday(const std::chrono::local_days& dp) noexcept;  | 
(4) | (since C++20) | 
Constructs a year_month_weekday object.
1) Default constructor leaves the fields uninitialized.
2) Constructs a 
year_month_weekday object storing the year y, the month m, the weekday wdi.weekday() and the weekday index wdi.index().3) Constructs a 
year_month_weekday object corresponding to the date represented by dp. For any year_month_weekday object storing a valid date, converting it to sys_days and back yields the same value. This constructor defines an implicit conversion from sys_days to year_month_weekday.4) Constructs a 
year_month_weekday object corresponding to the date represented by dp. Equivalent to year_month_weekday(sys_days(dp.time_since_epoch())).Notes
A year_month_weekday can also be created by combining one of the partial-date types std::chrono::year_month and std::chrono::month_weekday with the missing component (indexed weekday and year, respectively) using operator/.
See also
|    (C++20)  | 
   conventional syntax for Gregorian calendar date creation   (function)  |