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

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std::chrono::year
constexpr std:: chrono :: year & operator ++ ( ) noexcept ;
(1) (since C++20)
constexpr std:: chrono :: year operator ++ ( int ) noexcept ;
(2) (since C++20)
constexpr std:: chrono :: year & operator -- ( ) noexcept ;
(3) (since C++20)
constexpr std:: chrono :: year operator -- ( int ) noexcept ;
(4) (since C++20)

Adds or subtracts 1 from the year value.

1,2) Performs * this + = std:: chrono :: years { 1 } ; .
3,4) Performs * this - = std:: chrono :: years { 1 } ; .

Parameters

(none)

Return value

1,3) A reference to this year after modification.
2,4) A copy of the year made before 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()
{
    std::cout << std::boolalpha;
 
    std::chrono::year y{2020};
    std::cout << (++y == std::chrono::year(2021)) << ' ';
    std::cout << (--y == std::chrono::year(2020)) << '\n';
 
    using namespace std::literals::chrono_literals;
    y = 32767y;
    y++; //← unspecified, see ↑ Notes ↑
    std::cout << static_cast<int>(y) << '\n';
}

Possible output: 

true true
-32768

See also

adds or subtracts a number of years from a year
(public member function)
(C++20)
performs arithmetic on year s
(function)
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