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

 

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C-style date and time

 

std::chrono::year_month_day_last

Member functions

year_month_day_last::year_month_day_last

year_month_day_last::operator+=year_month_day_last::operator-=

year_month_day_last::yearyear_month_day_last::monthyear_month_day_last::dayyear_month_day_last::month_day_last

year_month_day_last::operator sys_daysyear_month_day_last::operator local_days

year_month_day_last::ok

Nonmember functions

operator==operator<=>

operator+operator-

operator<<

Helper classes

formatter<std::chrono::year_month_day_last>

 

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

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(15);
    std::cout << (ymdl.day() == std::chrono::day(30)) << ' '
              << (ymdl.month() == std::chrono::November) << ' '
              << (ymdl.year() == std::chrono::year(2035)) << ' ';
    ymdl -= std::chrono::months(6);
    std::cout << (ymdl.day() == std::chrono::day(31)) << ' '
              << (ymdl.month() == std::chrono::May) << ' '
              << (ymdl.year() == std::chrono::year(2035)) << '\n';
}

Output:

true true true true true true

See also

operator+operator- (C++20)

adds or subtracts a year_month_day_last and some number of years or months (function)