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

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< cpp‎ | chrono‎ | year
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std::chrono::year
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 ]

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

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