std::literals::chrono_literals::operator""min

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< cpplrm; | chrono
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C-style date and time
Defined in header <chrono>
constexpr chrono::minutes operator "" min(unsigned long long mins);
(1) (since C++14)
constexpr chrono::duration</*unspecified*/, ratio<60,1>>
operator "" min(long double mins);
(2) (since C++14)

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

1) integer literal, returns exactly std::chrono::minutes(mins)
2) floating-point literal, returns a floating-point duration equivalent to std::chrono::minutes

Parameters

minutes - the number of minutes

Return value

The std::chrono::duration literal.

Possible implementation

constexpr std::chrono::minutes operator ""min(unsigned long long m)
{
    return std::chrono::minutes(m);
}
constexpr std::chrono::duration<long double,
                                std::ratio<60,1>> operator ""min(long double m)
{
    return std::chrono::duration<long double, ratio<60,1>> (m);
}

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 lesson = 45min;
    auto halfmin = 0.5min;
    std::cout << "one lesson is " << lesson.count() << " minutes\n"
              << "half a minute is " << halfmin.count() << " minutes\n";
}

Output:

one lesson is 45 minutes
half a minute is 0.5 minutes

See also

constructs new duration
(public member function of std::chrono::duration)