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
.
*this = *this + dy;
*this = *this + dm;
*this = *this - dy;
*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.
#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
(C++20) | adds or subtracts a year_month_day_last and some number of years or months (function) |
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