std::chrono::weekday::operator+=, std::chrono::weekday::operator-=

constexpr std::chrono::weekday& operator+=(const std::chrono::days& d) noexcept;
(1) (since C++20)
constexpr std::chrono::weekday& operator-=(const std::chrono::days& d) noexcept;
(2) (since C++20)

Adds or subtracts d.count() from the weekday value, reducing the result modulo 7 to an integer in the range [0, 6].

1) Performs *this = *this + d;
2) Performs *this = *this - d;

Return value

A reference to this weekday after modification.

Notes

After a call to one of these functions, ok() is always true if no overflow occurred during the operation.

Example

See also

increments or decrements the weekday
(public member function)
performs arithmetic on weekdays
(function)

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