std::chrono::month_weekday_last::ok

 

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std::chrono::month_weekday_last

成员函数

month_weekday_last::month_weekday_last

month_weekday_last::monthmonth_weekday_last::weekday_last

month_weekday_last::ok

非成员函数

operator==

operator<<

辅助类

formatter<std::chrono::month_weekday_last>

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

 

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

检查所包含的 month 和 weekday_last 对象是否有效。

返回值

month().ok() && weekday_last().ok()

示例

运行此代码

#include <chrono>
#include <iostream>
 
int main()
{
    std::cout << std::boolalpha;
 
    auto mwdl{std::chrono::March/std::chrono::Wednesday[std::chrono::last]};
    std::cout << (mwdl.ok()) << ' ';
    mwdl = {std::chrono::month(3)/std::chrono::weekday(42)[std::chrono::last]}; 
    std::cout << (mwdl.ok()) << '\n';
}

输出

true false