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

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< cpp‎ | chrono‎ | year
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C-style date and time
constexpr std::chrono::year operator+ ( ) noexcept ;
(1) (since C++20)
constexpr std::chrono::year operator- ( ) noexcept ;
(2) (since C++20)

Applies the unary operators to the year value.

1) Returns a copy of *this.
2) Returns a year whose year value is the negation of that of *this.

Return value

1) *this
2) std::chrono::year ( - int ( *this) )

Example

#include <chrono>
#include <iostream>
 
int main()
{
    constexpr std::chrono::year y{2020};
    constexpr auto ny = -y;
    std::cout << "The year " << (int)y << " negated is " << (int)ny << '\n';
}

Output:

The year 2020 negated is -2020