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

 

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C-style date and time

 

std::chrono::month

Member functions

month::month

month::operator++month::operator--

month::operator+=month::operator-=

month::operator unsigned

month::ok

Nonmember functions

operator==operator<=>

operator+operator-

operator<<

from_stream

Helper classes

formatter<std::chrono::month>

 

constexpr std::chrono::month& operator++() noexcept;	(1)	(since C++20)
constexpr std::chrono::month operator++(int) noexcept;	(2)	(since C++20)
constexpr std::chrono::month& operator--() noexcept;	(3)	(since C++20)
constexpr std::chrono::month operator--(int) noexcept;	(4)	(since C++20)

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

1-2) Performs *this += std::chrono::months{1};

3-4) Performs *this -= std::chrono::months{1};

Parameters

(none)

Return value

1,3) a reference to this month after modification

2,4) a copy of the month made before modification

Notes

After a call to one of these functions, ok() is always true.

Example

Run this code

#include <iostream>
#include <chrono>
 
int main()
{
 
    std::chrono::month m {6};
 
    ++m;
    if (m == std::chrono::month(7)) {
        std::cout << "Month incremented correctly" << "\n";
    } else {
        std::cout << "Month not incremented correctly" << "\n";
    }
 
    --m;
    if (m == std::chrono::month(6)) {
        std::cout << "Month decremented correctly" << "\n";
    } else {
        std::cout << "Month not decremented correctly" << "\n";
    }
 
}

Output:

Month incremented correctly
Month decremented correctly

See also

operator+=operator-=	adds or subtracts a number of months (public member function)
operator+operator-	performs arithmetic on months (function)