std::chrono::year::operator+=,std::chrono::year::operator-= (3) Linux Manual Page
std::chrono::year::operator+=,std::chrono::year::operator-= – std::chrono::year::operator+=,std::chrono::year::operator-= Synopsis 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…
