std::chrono::operator+, std::chrono::operator- (std::chrono::day)

constexpr std::chrono::day operator+(const std::chrono::day&  d,
                                     const std::chrono::days& ds) noexcept;
(1) (since C++20)
constexpr std::chrono::day operator+(const std::chrono::days& ds,
                                     const std::chrono::day&  d) noexcept;
(2) (since C++20)
constexpr std::chrono::day operator-(const std::chrono::day&  d,
                                     const std::chrono::days& ds) noexcept;
(3) (since C++20)
constexpr std::chrono::days operator-(const std::chrono::day& x,
                                      const std::chrono::day& y) noexcept;
(4) (since C++20)
1-2) Adds ds.count() days to d.
3) Subtracts ds.count() days from d.
4) Calculate the difference, in days, between two day x and y.

Return value

1-2) std::chrono::day(unsigned(d) + ds.count())
3) std::chrono::day(unsigned(d) - ds.count())
4) std::chrono::days(int(unsigned(x)) - int(unsigned(y)))

Notes

For (1-3), if the result would be outside the range [0, 255], the actual stored value is unspecified.

Example

See also

increments or decrements the day
(public member function)
adds or subtracts a number of days
(public member function)

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