std::chrono::year_month::operator+=, std::chrono::year_month::operator-=

 

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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>

 

constexpr std::chrono::year_month& operator+=(const std::chrono::years& dy) const noexcept;	(1)	(C++20 起)
constexpr std::chrono::year_month& operator+=(const std::chrono::months& dm) const noexcept;	(2)	(C++20 起)
constexpr std::chrono::year_month& operator-=(const std::chrono::years& dy) const noexcept;	(3)	(C++20 起)
constexpr std::chrono::year_month& operator-=(const std::chrono::months& dm) const noexcept;	(4)	(C++20 起)

以时长 dy 或 dm 为程度修改时间点 *this 。

1) 等价于 *this = *this + dy;

2) 等价于 *this = *this + dm;

3) 等价于 *this = *this - dy;

4) 等价于 *this = *this - dm;

对于能转换到 std::chrono::years 与 std::chrono::months 两者的时长，若调用有歧义，则偏好 years 重载 (1,3) 。

参阅

operator+operator- (C++20)

进行 year_month 上的算术 (函数)