std::chrono::weekday_indexed::index

 

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std::chrono::weekday_indexed

成员函数

weekday_indexed::weekday_indexed

weekday_indexed::weekday

weekday_indexed::index

weekday_indexed::ok

非成员函数

operator==

operator<<

辅助类

formatter<std::chrono::weekday_indexed>

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

 

constexpr unsigned index() const noexcept;		(C++20 起)

访问存储于 *this 的索引。

返回值

存储于 *this 的索引。

示例

运行此代码

#include <chrono>
#include <iostream>
 
int main()
{
    std::cout << std::boolalpha;
 
    std::chrono::weekday_indexed wdi {std::chrono::Tuesday[2]}; // 某月第二个星期二
    std::cout << (std::chrono::year_month_day{wdi/10/2019} == 
                  std::chrono::year_month_day{std::chrono::October/8/2019}) << ' ';
 
    wdi = {wdi.weekday()[wdi.index() + 2]}; // 第二个星期二 => 第四个星期二
    std::cout << (std::chrono::year_month_day{wdi/10/2019} == 
                  std::chrono::year_month_day{std::chrono::October/22/2019}) << '\n';
}

输出：

true true