Scroll to navigation

std::literals::chrono_literals::operator""min(3) C++ Standard Libary std::literals::chrono_literals::operator""min(3)

NAME

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

Synopsis


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


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


mins - 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

// Run this code


#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


constructor constructs new duration
(public member function of std::chrono::duration<Rep,Period>)

2022.07.31 http://cppreference.com