std::literals::chrono_literals:: operator""ns

Forms a std::chrono::duration literal representing nanoseconds.

Parameters

Return value

The std::chrono::duration literal.

Possible implementation

constexpr std::chrono::nanoseconds operator""ns(unsigned long long ns)
{
    return std::chrono::nanoseconds(ns);
}
constexpr std::chrono::duration<long double, std::nano> operator""ns(long double ns)
{
    return std::chrono::duration<long double, std::nano>(ns);
}

Notes

This operator is declared in the namespace std :: literals :: chrono_literals , where both literals and chrono_literals are inline namespaces . Access to this operator can be gained with:

• using namespace std :: literals ,
• using namespace std :: chrono_literals , or
• 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 <chrono>
#include <iostream>
 
int main()
{
    using namespace std::chrono_literals;
    auto d1{250ns};
    std::chrono::nanoseconds d2{1us};
    std::cout << d1 << " = " << d1.count() << " nanoseconds\n"
              << d2 << " = " << d2.count() << " nanoseconds\n";
}

250ns = 250 nanoseconds
1000ns = 1000 nanoseconds

See also