std::chrono::ceil(std::chrono::duration)
From cppreference.com
| Defined in header <chrono>
|
||
template< class ToDuration, class Rep, class Period >
constexpr ToDuration ceil( const std::chrono::duration<Rep, Period>& d );
|
(since C++17) | |
Returns the smallest duration t representable in ToDuration that is greater or equal to d.
The function does not participate in the overload resolution unless ToDuration is a specialization of std::chrono::duration.
Parameters
| d | - | duration to convert |
Return value
d rounded up to a duration of type ToDuration.
Possible implementation
namespace detail
{
template<class> inline constexpr bool is_duration_v = false;
template<class Rep, class Period> inline constexpr bool is_duration_v<
std::chrono::duration<Rep, Period>> = true;
}
template<class To, class Rep, class Period,
class = std::enable_if_t<detail::is_duration_v<To>>>
constexpr To ceil(const std::chrono::duration<Rep, Period>& d)
{
To t = std::chrono::duration_cast<To>(d);
if (t < d)
return t + To{1};
return t;
}
|
Example
Run this code
#include <chrono>
#include <iostream>
int main()
{
using namespace std::chrono_literals;
using Min = std::chrono::minutes;
std::cout
<< std::showpos
<< "ceil(+2.4min) = " << std::chrono::ceil<Min>(+2.4min).count() << "min\n"
<< "ceil(-2.4min) = " << std::chrono::ceil<Min>(-2.4min).count() << "min\n"
<< "ceil(+0.0min) = " << std::chrono::ceil<Min>(+0.0min).count() << "min\n";
}
Output:
ceil(+2.4min) = +3min
ceil(-2.4min) = -2min
ceil(+0.0min) = +0min
