std::chrono::operator+, std::chrono::operator- (std::chrono::day)
Defined in header <chrono> |
||
---|---|---|
constexpr std::chrono::day operator+( const std::chrono::day& d, const std::chrono::days& ds ) noexcept; |
(1) | (since C++20) |
constexpr std::chrono::day operator+( const std::chrono::days& ds, const std::chrono::day& d ) noexcept; |
(2) | (since C++20) |
constexpr std::chrono::day operator-( const std::chrono::day& d, const std::chrono::days& ds ) noexcept; |
(3) | (since C++20) |
constexpr std::chrono::days operator-( const std::chrono::day& x, const std::chrono::day& y ) noexcept; |
(4) | (since C++20) |
1-2) Adds
ds.count()
days to
d
.
3) Subtracts
ds.count()
days from
d
.
4) Calculate the difference, in days, between two
day
x
and
y
.
Return value
1-2)
std::chrono::day(unsigned(d) + ds.count())
3)
std::chrono::day(unsigned(d) - ds.count())
4)
std::chrono::days(int(unsigned(x)) - int(unsigned(y)))
Notes
For (1-3), if the result would be outside the range [0, 255], the actual stored value is unspecified.
Example
#include <chrono> #include <cassert> int main() { std::chrono::day d {15}; d = d + std::chrono::days(2); assert(d == std::chrono::day(17)); d = d - std::chrono::days(3); assert(d == std::chrono::day(14)); constexpr std::chrono::days ds = std::chrono::day(16) - std::chrono::day(14); static_assert(ds == std::chrono::days(2)); }
See also
increments or decrements the day (public member function) |
|
adds or subtracts a number of days (public member function) |
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