std::chrono::month::operator++, std::chrono::month::operator--
From cppreference.com
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 <cassert>
#include <chrono>
#include <iostream>
int main()
{
std::chrono::month m{6};
++m;
assert(m == std::chrono::month(7));
--m;
assert(m == std::chrono::month(6));
m = std::chrono::December;
m++; // rounds up to January
assert(m.ok());
std::cout << unsigned(m) << '\n';
m = std::chrono::January;
m--; // rounds down to December
assert(m.ok());
std::cout << unsigned(m) << '\n';
}
Output:
1
12
See also
| adds or subtracts a number of months (public member function) | |
(C++20) |
performs arithmetic on months (function) |