std::chrono::operator==,<=>(std::chrono::year)

 

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std::chrono::year

成员函数

year::year

year::operator++year::operator--

year::operator+=year::operator-=

year::operator+year::operator-

year::is_leap

year::operator int

year::ok

year::min

year::max

非成员函数

operator==operator<=>

operator+operator-

operator<<

from_stream

operator""y

辅助类

formatter<std::chrono::year>

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

 

在标头 <chrono> 定义
constexpr bool operator==( const std::chrono::year& x,                            const std::chrono::year& y ) noexcept;	(1)	(C++20 起)
constexpr std::strong_ordering operator<=>( const std::chrono::year& x,                                             const std::chrono::year& y ) noexcept;	(2)	(C++20 起)

比较二个 std::chrono::year x 与 y 。

<、 <=、 >、 >= 及 != 运算符分别从 operator<=> 与 operator== 合成。

返回值

1) int(x) == int(y)

2) int(x) <=> int(y)

示例

运行此代码

#include <iostream>
#include <chrono>
 
int main()
{
    using namespace std::chrono;
 
    constexpr year y1{2020};
    constexpr year y2{2021};
 
    if (y1 == y2) {
        std::cout << "y1 and y2 are equal\n";
    } else {
        std::cout << "y1 and y2 are not equal\n";
    }
 
    static_assert(
        (2020y < 2023y) && (2020y == 2020y) && (2020y <= 2023y) &&
        (2023y > 2020y) && (2023y != 2020y) && (2023y >= 2020y)
    );
}

输出：

y1 and y2 are not equal