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

constexpr std::chrono::month& operator+=(const std::chrono::months& m) noexcept;
(1) (since C++20)
constexpr std::chrono::month& operator+=(const std::chrono::months& m) noexcept;
(2) (since C++20)

Adds or subtracts m.count() from the month value, reducing the result modulo 12 to an integer in the range [1, 12].

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

Return value

A reference to this month 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 month
(public member function)
performs arithmetic on months
(function)

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