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

 

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通用实用程序 日期和时间 函数对象 格式化库 (C++20) bitset hash (C++11) 关系运算符 (C++20 中已弃用) rel_ops::operator!=rel_ops::operator>     rel_ops::operator<=rel_ops::operator>= 整数比较函数 cmp_equalcmp_lesscmp_less_than (C++20)(C++20)(C++20)    cmp_not_equalcmp_greatercmp_greater_than (C++20)(C++20)(C++20) in_range (C++20) 交换 和 类型操作 swap ranges::swap (C++20) exchange (C++14) declval (C++11) to_underlying (C++23) forward (C++11) forward_like (C++23) move (C++11) move_if_noexcept (C++11) as_const (C++17) 通用词汇类型 pair tuple (C++11) optional (C++17) any (C++17) variant (C++17) tuple_size (C++11) tuple_element (C++11) apply (C++17) make_from_tuple (C++17) expected (C++23) 基本字符串转换 to_chars (C++17) from_chars (C++17) chars_format (C++17) to_chars_result (C++17) from_chars_result (C++17)

 

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is_amis_pm (C++20)(C++20)	make12make24 (C++20)(C++20)	hh_mm_ss (C++20)
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day (C++20) month (C++20) year (C++20) weekday (C++20) operator/ (C++20) year_month_day (C++20)	year_month_day_last (C++20) year_month_weekday (C++20) year_month_weekday_last (C++20)   weekday_indexed (C++20) weekday_last (C++20) month_day (C++20)	month_day_last (C++20) month_weekday (C++20) month_weekday_last (C++20) year_month (C++20) last_speclast (C++20)(C++20)
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C 样式日期和时间

 

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)

 

定义在头文件 <chrono> 中
constexpr bool operator==( const std::chrono::year& x,                            const std::chrono::year& y ) noexcept;	(1)	(自 C++20 起)
constexpr std::strong_ordering operator<=>( const std::chrono::year& x,                                             const std::chrono::year& y ) noexcept;	(2)	(自 C++20 起)

比较两个 std::chrono::year x 和 y。

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

返回值

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

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

示例

运行此代码

#include <chrono>
#include <iostream>
 
int main()
{
    using namespace std::chrono;
 
    constexpr year y1{2020};
    constexpr year y2{2021};
 
    std::cout << std::boolalpha << (y1 != y2) << '\n';
 
    static_assert((2020y < 2023y) && (2020y == 2020y) && (2020y <= 2023y) &&
                  (2023y > 2020y) && (2023y != 2020y) && (2023y >= 2020y));
}

输出

true