std::chrono::year_month::ok

 

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std::chrono::year_month

成员函数

year_month::year_month

year_month::yearyear_month::month

year_month::operator+=year_month::operator-=

year_month::ok

非成员函数

operator==operator<=>

operator+operator-

operator<<

from_stream

辅助类

formatter<std::chrono::year_month>

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

 

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

检查存储于此对象的 year 和 month 值是否均合法。

返回值

year().ok() && month().ok()

示例

运行此代码

#include <chrono>
using namespace std::chrono_literals;
 
int main()
{
    constexpr std::chrono::year_month ym1{3030y, std::chrono::July};
    static_assert(ym1.ok());
 
    constexpr std::chrono::year_month ym2{std::chrono::year(2020)/16};
    static_assert(!ym2.ok());
}