NAME¶

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

Synopsis¶

constexpr std::chrono::year_month_weekday& (1) (since C++20)
operator+=( const std::chrono::years& dy ) const noexcept;
constexpr std::chrono::year_month_weekday& (2) (since C++20)
operator+=( const std::chrono::months& dm ) const noexcept;
constexpr std::chrono::year_month_weekday& (3) (since C++20)
operator-=( const std::chrono::years& dy ) const noexcept;
constexpr std::chrono::year_month_weekday& (4) (since C++20)
operator-=( const std::chrono::months& dm ) const noexcept;

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.

Example¶

// Run this code

#include <iostream>
#include <chrono>

int main()
{
std::cout << std::boolalpha;

auto ymwi {1/std::chrono::Wednesday[2]/2021};
ymwi += std::chrono::years(5);
std::cout << (static_cast<std::chrono::year_month_day>(ymwi) ==
std::chrono::year(2026)/1/14) << ' ';
ymwi -= std::chrono::months(1);
std::cout << (static_cast<std::chrono::year_month_day>(ymwi) ==
std::chrono::day(10)/12/2025) << '\n';
}

Output:¶

true true

See also¶

operator+ adds or subtracts a year_month_weekday and some number of years or months
operator- (function)
(C++20)