std::chrono::month_weekday::ok

 

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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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C 样式日期和时间

 

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 bool ok() const noexcept;		(自 C++20 起)

检查包含的 month 和 weekday_indexed 对象是否有效。

返回值

month().ok() && weekday_indexed().ok()

示例

运行此代码

#include <cassert>
#include <chrono>
 
int main()
{
    auto mwdi{std::chrono::March/std::chrono::Friday[1]};
    assert(mwdi.ok());
 
    mwdi = {std::chrono::month(17)/std::chrono::Friday[1]}; 
    assert(not mwdi.ok());
 
    mwdi = {std::chrono::March/std::chrono::Friday[-4]}; 
    assert(not mwdi.ok());
}