std::chrono::operator+, std::chrono::operator- (std::chrono::weekday)
constexpr std::chrono::weekday operator+(const std::chrono::weekday& wd,
const std::chrono::days& d) noexcept;
| (1) | (since C++20) |
constexpr std::chrono::weekday operator+(const std::chrono::days& d,
const std::chrono::weekday& wd) noexcept;
| (2) | (since C++20) |
constexpr std::chrono::weekday operator-(const std::chrono::weekday& wd,
const std::chrono::days& d) noexcept;
| (3) | (since C++20) |
constexpr std::chrono::days operator-(const std::chrono::weekday& wd1,
const std::chrono::weekday& wd2) noexcept;
| (4) | (since C++20) |
1-2) Adds
d.count() days to wd. The weekday value held in the result is computed by first evaluating static_cast<long long>(unsigned(wd)) + d.count() and reducing it modulo 7 to an integer in the range [0, 6].
3) Subtracts
d.count() days from wd. Equivalent to return wd + -d;
4) If
wd1.ok() and wd2.ok() are both true, returns a std::chrono::days value d such that d.count() is in the range [0, 6] and wd2 + d == wd1. Otherwise the returned value is unspecified.Return value
1-3) A
std::chrono::weekday holding a weekday value calculated as described above.
4) A
std::chrono::days representing the distance between wd1 and wd2.Notes
As long as the computation doesn't overflow, (1-3) always return a valid weekday even if wd.ok() is false.
Example
See also
| increments or decrements the weekday (public member function) |
|
| adds or subtracts a number of days (public member function) |
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