std::chrono::weekday_last::ok

 

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std::chrono::weekday_last

成员函数

weekday_last::weekday_last

weekday_last::weekday

weekday_last::ok

非成员函数

operator==

operator<<

辅助类

formatter<std::chrono::weekday_last>

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

 

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

检查存储于 *this 的 weekday 对象是否合法。

返回值

weekday().ok()

示例

运行此代码

#include <chrono>
#include <iostream>
 
int main()
{
    std::cout << std::boolalpha;
 
    auto wdl{std::chrono::Tuesday[std::chrono::last]};
    std::cout << (wdl.ok()) << ' ';
 
    wdl = {std::chrono::weekday(42)[std::chrono::last]};
    std::cout << (wdl.ok()) << '\n';
}

输出：

true false