std::chrono::year_month_weekday_last::operator+=, std::chrono::year_month_weekday_last::operator-=
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                    < cpp | chrono | year month weekday last
                    
                                                            
                    
| 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) are preferred if the call would otherwise be ambiguous.
See also
| adds or subtracts a year_month_weekday_lastand some number of years or months(function) |