std::chrono::weekday_indexed::ok

 

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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 bool ok() const noexcept;		(C++20 起)

检查存储于 *this 的 weekday 对象和索引是否均合法。

返回值

若 weekday().ok() == true 且 index() 在范围 [1, 5] 中则为 true。否则为 false。

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]};
    std::cout << (wdi.ok()) << ' ';
    wdi = {std::chrono::weekday(42)[2]}; 
    std::cout << (wdi.ok()) << ' ';
    wdi = {std::chrono::Tuesday[-4]}; 
    std::cout << (wdi.ok()) << '\n';
}

输出：

true false false