std::chrono::year_month::operator+=,std::chrono::year_month::operator-=(3) | C++ Standard Libary | std::chrono::year_month::operator+=,std::chrono::year_month::operator-=(3) |
NAME¶
std::chrono::year_month::operator+=,std::chrono::year_month::operator-= - std::chrono::year_month::operator+=,std::chrono::year_month::operator-=
Synopsis¶
constexpr std::chrono::year_month& (1) (since
C++20)
operator+=( const std::chrono::years& dy ) const noexcept;
constexpr std::chrono::year_month& (2) (since C++20)
operator+=( const std::chrono::months& dm ) const noexcept;
constexpr std::chrono::year_month& (3) (since C++20)
operator-=( const std::chrono::years& dy ) const noexcept;
constexpr std::chrono::year_month& (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 ym {std::chrono::day(1)/7/2023};
ym -= std::chrono::years {2};
std::cout << (ym.month() == std::chrono::July) << ' '
<< (ym.year() == std::chrono::year(2021)) << ' ';
ym += std::chrono::months {7};
std::cout << (ym.month() == std::chrono::month(2)) << ' '
<< (ym.year() == std::chrono::year(2022)) << '\n';
}
Output:¶
true true true true
See also¶
operator+ performs arithmetic on year_month
operator- (function)
(C++20)
2022.07.31 | http://cppreference.com |