Namespaces
Variants
Views
Actions

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

From cppreference.com
 
 
Utilities library
Language support
Type support (basic types, RTTI)
Library feature-test macros (C++20)
Dynamic memory management
Program utilities
Coroutine support (C++20)
Variadic functions
Debugging support
(C++26)
Three-way comparison
(C++20)
(C++20)(C++20)(C++20)
(C++20)(C++20)(C++20)
General utilities
Date and time
Function objects
Formatting library (C++20)
(C++11)
Relational operators (deprecated in C++20)
Integer comparison functions
(C++20)(C++20)(C++20)   
(C++20)
Swap and type operations
(C++14)
(C++11)
(C++11)
(C++11)
(C++17)
Common vocabulary types
(C++11)
(C++17)
(C++17)
(C++17)
(C++11)
(C++17)
(C++23)
Elementary string conversions
(C++17)
(C++17)

 
 
 
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.

[edit] 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

[edit] See also

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