std::chrono::month_weekday::month, std::chrono::month_weekday::weekday_indexed

 

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std::chrono::month_weekday

成员函数

month_weekday::month_weekday

month_weekday::monthmonth_weekday::weekday_indexed

month_weekday::ok

非成员函数

operator==

operator<<

辅助类

formatter<std::chrono::month_weekday>

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

 

constexpr std::chrono::month month() const noexcept;	(1)	(自 C++20 起)
constexpr std::chrono::weekday_indexed weekday_indexed() const noexcept;	(2)	(自 C++20 起)

检索存储在 *this 中的 month 和 weekday_indexed 对象的副本。

返回值

1) 存储在 *this 中的 std::chrono::month 对象的副本。

2) 存储在 *this 中的 std::chrono::weekday_indexed 对象的副本。

示例

运行此代码

#include <chrono>
#include <iostream>
 
int main()
{
    std::cout << std::boolalpha;
 
    auto mwdi{std::chrono::March/std::chrono::Friday[1]}; // 1st Friday in a March
    std::cout << (std::chrono::year_month_day{mwdi/2024} == 
                  std::chrono::year_month_day{std::chrono::March/1/2024})
                  << ' ';
    auto index = mwdi.weekday_indexed().index();
    auto weekday = mwdi.weekday_indexed().weekday();
    mwdi = {mwdi.month(), weekday[index + 4]}; // 5th Friday in a March
    std::cout << (std::chrono::year_month_day{mwdi/2024} == 
                  std::chrono::year_month_day{std::chrono::March/29/2024})
                  << '\n';
}

输出

true true