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

Since C++20

Modifies the time point *this represents by the duration dy or dm.

# Declarations

constexpr std::chrono::year_month&
operator+=( const std::chrono::years& dy ) const noexcept;

(since C++20)

constexpr std::chrono::year_month&
operator+=( const std::chrono::months& dm ) const noexcept;

(since C++20)

constexpr std::chrono::year_month&
operator-=( const std::chrono::years& dy ) const noexcept;

(since C++20)

constexpr std::chrono::year_month&
operator-=( const std::chrono::months& dm ) const noexcept;

(since C++20)

# Example

#include <cassert>
#include <chrono>
 
int main()
{
    auto ym{std::chrono::day(1)/7/2023};
 
    ym -= std::chrono::years{2};
    assert(ym.month() == std::chrono::July);
    assert(ym.year() == std::chrono::year(2021));
 
    ym += std::chrono::months{7};
    assert(ym.month() == std::chrono::month(2));
    assert(ym.year() == std::chrono::year(2022));
}

# See also

operator+operator-