std::chrono::year_month_weekday::operator+=, std::chrono::year_month_weekday::operator-=
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std::chrono::year_month_weekday
Member functions
year_month_weekday::operator+=year_month_weekday::operator-=
Nonmember functions
Helper classes
constexpr std::chrono::year_month_weekday &
operator+=( const std::chrono::years & dy ) const noexcept;
(1)
(since C++20)
operator+=( const std::chrono::years & dy ) const noexcept;
constexpr std::chrono::year_month_weekday &
operator+=( const std::chrono::months & dm ) const noexcept;
(2)
(since C++20)
operator+=( const std::chrono::months & dm ) const noexcept;
constexpr std::chrono::year_month_weekday &
operator-=( const std::chrono::years & dy ) const noexcept;
(3)
(since C++20)
operator-=( const std::chrono::years & dy ) const noexcept;
constexpr std::chrono::year_month_weekday &
operator-=( const std::chrono::months & dm ) const noexcept;
(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.
[edit] Example
Run this code
#include <cassert> #include <chrono> #include <iostream> int main() { auto ymwi{1/std::chrono::Wednesday [2]/2021}; std::cout << ymwi << '\n'; ymwi += std::chrono::years (5); std::cout << ymwi << '\n'; assert (static_cast<std::chrono::year_month_day >(ymwi) == std::chrono::year (2026)/1/14); ymwi -= std::chrono::months (1); std::cout << ymwi << '\n'; assert (static_cast<std::chrono::year_month_day >(ymwi) == std::chrono::day (10)/12/2025); }
Output:
2021/Jan/Wed[2] 2026/Jan/Wed[2] 2025/Dec/Wed[2]