std::literals::chrono_literals::operator""us
Defined in header <chrono> | ||
|---|---|---|
constexpr std::chrono::microseconds operator "" us(unsigned long long us); | (1) | (since C++14) |
constexpr std::chrono::duration</*unspecified*/,
std::micro> operator "" us(long double us);
| (2) | (since C++14) |
Forms a std::chrono::duration literal representing microseconds.
std::chrono::microseconds(us) std::chrono::microseconds
Parameters
| us | - | the number of microseconds |
Return value
The std::chrono::duration literal.
Possible implementation
constexpr std::chrono::microseconds operator ""us(unsigned long long us)
{
return std::chrono::microseconds(us);
}
constexpr std::chrono::duration<long double, std::micro> operator ""us(long double us)
{
return std::chrono::duration<long double, std::micro>(us);
} |
Notes
These operators are declared in the namespace std::literals::chrono_literals, where both literals and chrono_literals are inline namespaces. Access to these operators can be gained with using namespace std::literals, using namespace std::chrono_literals, and using namespace std::literals::chrono_literals.
In addition, within the namespace std::chrono, the directive using namespace literals::chrono_literals; is provided by the standard library, so that if a programmer uses using namespace std::chrono; to gain access to the classes in the chrono library, the corresponding literal operators become visible as well.
Example
#include <iostream>
#include <chrono>
int main()
{
using namespace std::chrono_literals;
auto d1 = 250us;
std::chrono::microseconds d2 = 1ms;
std::cout << "250us = " << d1.count() << " microseconds\n"
<< "1ms = " << d2.count() << " microseconds\n";
}Output:
250us = 250 microseconds 1ms = 1000 microseconds
See also
| constructs new duration (public member function of std::chrono::duration<Rep,Period>) |
© cppreference.com
Licensed under the Creative Commons Attribution-ShareAlike Unported License v3.0.
http://en.cppreference.com/w/cpp/chrono/operator_q__q_us