std::chrono::year_month_weekday_last::operator+=, std::chrono::year_month_weekday_last::

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Date and time library
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chrono I/O
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C-style date and time
constexpr std::chrono::year_month_weekday_last &
    operator+ = ( const std::chrono::years & dy ) const noexcept ;
(1) (since C++20)
constexpr std::chrono::year_month_weekday_last &
    operator+ = ( const std::chrono::months & dm ) const noexcept ;
(2) (since C++20)
constexpr std::chrono::year_month_weekday_last &
    operator- = ( const std::chrono::years & dy ) const noexcept ;
(3) (since C++20)
constexpr std::chrono::year_month_weekday_last &
    operator- = ( const std::chrono::months & dm ) const noexcept ;
(4) (since C++20)

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

1) Equivalent to *this = *this + dy;
2) Equivalent to *this = *this + dm;
3) Equivalent to *this = *this - dy;
4) Equivalent to *this = *this - dm;

For durations that are convertible to both std::chrono::years and std::chrono::months, the years overloads (1,3)

Example

#include <chrono>
#include <iostream>
using namespace std::chrono;
 
int main()
{
    auto ymwdl{August/Friday[last]/2022};
    std::cout << year_month_day{ymwdl} << '\n';
    ymwdl += months(2);
    std::cout << year_month_day{ymwdl} << '\n';
    ymwdl -= years(1); 
    std::cout << year_month_day{ymwdl} << '\n';
}

Output:

2022-08-26
2022-10-28
2021-10-29

See also

adds or subtracts a year_month_weekday_last and some number of years or months
(function)