std::chrono::year::operator++, std::chrono::year::operator--
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                    |   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 years (function)  |