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

 

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std::chrono::year

Member functions

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

Nonmember functions

operator==operator<=>

operator+operator-

operator<<

from_stream

operator""y

Helper classes

formatter<std::chrono::year>

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

 

constexpr std::chrono::year& operator+=( const std::chrono::years& y ) noexcept;	(1)	(since C++20)
constexpr std::chrono::year& operator-=( const std::chrono::years& y ) noexcept;	(2)	(since C++20)

Adds or subtracts y.count() years from the year value.

1) Equivalent to *this = *this + y;.

2) Equivalent to *this = *this - y;.

Return value

A reference to this year after modification.

Notes

If the result would be outside the range [-32767, 32767], the actual stored value is unspecified.

Example

Run this code

#include <chrono>
#include <iostream>
 
int main()
{
    using namespace std::literals::chrono_literals;
    std::cout << std::boolalpha;
 
    std::chrono::year y{2020};
 
    y += std::chrono::years(12);
    std::cout << (y == 2032y) << ' ';
 
    y -= std::chrono::years(33);
    std::cout << (y == 1999y) << '\n';
}

Output:

true true

See also

operator++operator++(int)operator--operator--(int)	increments or decrements the year (public member function)
operator+operator- (C++20)	performs arithmetic on years (function)