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

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

Adds or subtracts d.count() days from the day value.

1) Equivalent to *this = *this + d;
2) Equivalent to *this = *this - d;

Return value

A reference to this day after modification

Notes

If the result would be outside the range [0, 255], the actual stored value is unspecified.

Example

#include <cassert>
#include <chrono>
 
int main()
{
    std::chrono::day d {15};
 
    d += std::chrono::days(2);
    assert(d == std::chrono::day(17));
 
    d -= std::chrono::days{3};
    assert(d == std::chrono::day(14));
}

See also

 increments or decrements the day
(public member function)
(C++20)
 adds or subtracts a number of days and a day, or find the difference between two days
(function)