NAME¶

std::chrono::operator+,std::chrono::operator-(std::chrono::year_month_day_last) - std::chrono::operator+,std::chrono::operator-(std::chrono::year_month_day_last)

Synopsis¶

Defined in header <chrono>
constexpr std::chrono::year_month_day_last
operator+( const std::chrono::year_month_day_last& ymdl, const (since C++20)
std::chrono::months& dm ) noexcept;
constexpr std::chrono::year_month_day_last
operator+( const std::chrono::months& dm, const (since C++20)
std::chrono::year_month_day_last& ymdl ) noexcept;
constexpr std::chrono::year_month_day_last
operator+( const std::chrono::year_month_day_last& ymdl, const (since C++20)
std::chrono::years& dy ) noexcept;
constexpr std::chrono::year_month_day_last
operator+( const std::chrono::years& dy, const (since C++20)
std::chrono::year_month_day_last& ymdl ) noexcept;
constexpr std::chrono::year_month_day_last
operator-( const std::chrono::year_month_day_last& ymdl, const (since C++20)
std::chrono::months& dm ) noexcept;
constexpr std::chrono::year_month_day_last
operator-( const std::chrono::year_month_day_last& ymdl, const (since C++20)
std::chrono::years& dy ) noexcept;

1-2) Adds dm.count() months to the date represented by ymdl. The result has the same
year() and month() as std::chrono::year_month(ymdl.year(), ymdl.month()) + dm.
3-4) Adds dy.count() years to the date represented by ymdl. The result is equivalent
to std::chrono::year_month_day_last(ymdl.year() + dy, ymdl.month_day_last()).
5) Subtracts dm.count() months from the date represented by ymdl. Equivalent to ymdl
+ -dm.
6) Subtracts dy.count() years from the date represented by ymdl. Equivalent to ymdl
+ -dy.

For durations that are convertible to both std::chrono::years and
std::chrono::months, the years overloads (3,4,6) are preferred if the call would
otherwise be ambiguous.

Example¶

// Run this code

#include <iostream>
#include <chrono>

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

auto ymdl {11/std::chrono::last/2020};
ymdl = std::chrono::years(10) + ymdl;
std::cout << (ymdl == std::chrono::day(30)/
std::chrono::November/
std::chrono::year(2030)) << ' ';
ymdl = ymdl - std::chrono::months(6);
std::cout << (ymdl == std::chrono::day(31)/
std::chrono::May/
std::chrono::year(2030)) << '\n';
}

Output:¶

true true