std::literals::chrono_literals::operator""us

constexpr std::chrono::microseconds operator ""us( unsigned long long us );

constexpr std::chrono::duration</*unspecified*/, std::micro>
                                    operator ""us( long double us );

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

Parameters

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

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 <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";
}

250us = 250 microseconds
1ms = 1000 microseconds

See also