std::literals::chrono_literals:: operator""h

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

Parameters

Return value

The std::chrono::duration literal.

Possible implementation

constexpr std::chrono::hours operator""h(unsigned long long h)
{
    return std::chrono::hours(h);
}
 
constexpr std::chrono::duration<long double, ratio<3600,1>> operator""h(long double h)
{
    return std::chrono::duration<long double, std::ratio<3600,1>>(h);
}

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 day = 24h;
    auto halfhour = 0.5h;
    std::cout << "one day is " << day.count() << " hours (" << day << ")\n"
              << "half an hour is " << halfhour.count() << " hours ("
              << halfhour << ")\n";
}

one day is 24 hours (24h)
half an hour is 0.5 hours (0.5h)

See also