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 modification2,4) a copy of the 
year made before modificationNotes
If the result would be outside the range [-32767, 32767], the actual stored value is unspecified.
Example
| This section is incomplete Reason: no example  | 
See also
   adds or subtracts a number of years from a year  (public member function)  | |
   performs arithmetic on years  (public member function)  |