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

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< cpp‎ | chrono
 
 
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std::chrono::duration
Member functions
Non-member functions
Helper classes
 
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 .

[edit] Parameters

mins - the number of minutes

[edit] Return value

The std::chrono::duration literal.

[edit] 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);
}

[edit] 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.

[edit] Example

Run this code
#include <chrono>
#include <iostream>
 
int main()
{
 using namespace std::chrono_literals;
 auto lesson = 45min;
 auto halfmin = 0.5min;
 std::cout << "One lesson is " << lesson.count() << " minutes"
 " (" << lesson << ")\n"
 << "Half a minute is " << halfmin.count() << " minutes"
 " (" << halfmin << ")\n";
}

Output:

One lesson is 45 minutes (45min)
Half a minute is 0.5 minutes (0.5min)

[edit] See also

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