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

 

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std::chrono::day

成员函数

day::day

day::operator++day::operator--

day::operator+=day::operator-=

day::operator unsigned

day::ok

非成员函数

operator==operator<=>

operator+operator-

operator<<

from_stream

辅助类

formatter<std::chrono::day>

 

定义于头文件 <chrono>
constexpr bool operator==( const std::chrono::day& x,                            const std::chrono::day& y ) noexcept;	(1)	(C++20 起)
constexpr std::strong_ordering operator<=>( const std::chrono::day& x,                                             const std::chrono::day& y ) noexcept;	(2)	(C++20 起)

比较二个 std::chrono::day x 和 y 。

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

返回值

1) unsigned(x) == unsigned(y)

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

示例

运行此代码

#include <iostream>
#include <chrono>
 
int main()
{
    std::chrono::day d1{15};
    std::chrono::day d2{20};
 
    d1 == d2 ? std::cout << "d1 and d2 are equal\n"
             : std::cout << "d1 and d2 are not equal\n";
 
    using namespace std::literals::chrono_literals;
 
    std::cout << std::boolalpha
              << (6d < 9d) << ' ' << (6d == 6d) << ' ' << (6d <= 9d) << ' '
              << (9d > 6d) << ' ' << (9d != 6d) << ' ' << (9d >= 6d) << '\n';
}

输出：

d1 and d2 are not equal
true true true true true true