std::chrono::duration

 

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std::chrono::duration

Member functions

duration::duration

duration::operator=

duration::count

duration::zero

duration::min

duration::max

duration::operator+ duration::operator-

duration::operator++ duration::operator--

duration::operator+= duration::operator-= duration::operator*= duration::operator/= duration::operator%=

Non-member functions

common_type

operator+ operator- operator* operator/ operator%

operator== operator!= operator< operator<= operator> operator>=

duration_cast

Helper classes

treat_as_floating_point

duration_values

 

Defined in header <chrono>
template<     class Rep,     class Period = std::ratio<1> > class duration;		(since C++11)

Class template std::chrono::duration represents a time interval.

It consists of a count of ticks of type Rep and a tick period, where the tick period is a compile-time rational constant representing the number of seconds from one tick to the next.

The only data stored in a duration is a tick count of type Rep. If Rep is floating point, then the duration can represent fractions of ticks. Period is included as part of the duration's type, and is only used when converting between different durations.

Member types

Member type	Definition
rep	Rep, an arithmetic type representing the number of ticks
period	Period, a std::ratio representing the tick period (i.e. the number of seconds per tick)

Member functions

(constructor)	constructs new duration (public member function)
operator=	assigns the contents (public member function)
count	returns the count of ticks (public member function)
zero [static]	returns the special duration value zero (public static member function)
min [static]	returns the special duration value min (public static member function)
max [static]	returns the special duration value max (public static member function)
operator+ operator-	implements unary + and unary - (public member function)
operator++ operator++(int) operator-- operator--(int)	increments or decrements the tick count (public member function)
operator+= operator-= operator*= operator/= operator%=	implements compound assignment between two durations (public member function)

Non-member types

Type	Definition
std::chrono::nanoseconds	duration</*signed integer type of at least 64 bits*/, std::nano>
std::chrono::microseconds	duration</*signed integer type of at least 55 bits*/, std::micro>
std::chrono::milliseconds	duration</*signed integer type of at least 45 bits*/, std::milli>
std::chrono::seconds	duration</*signed integer type of at least 35 bits*/ >
std::chrono::minutes	duration</*signed integer type of at least 29 bits*/,std::ratio<60>>
std::chrono::hours	duration</*signed integer type of at least 23 bits*/, std::ratio<3600>>

Non-member functions

std::common_type<std::chrono::duration>	specializes the std::common_type trait (class template specialization)
operator+ operator- operator* operator/ operator%	implements arithmetic operations with durations as arguments (function template)
operator== operator!= operator< operator<= operator> operator>=	compares two durations (function template)
duration_cast	converts a duration to another, with a different tick interval (function template)

Helper classes

treat_as_floating_point	indicates that a duration is convertible to duration with different tick period (class template)
duration_values	constructs zero, min, and max values of a tick count of given type (class template)

Example

This example shows how to define several custom duration types and convert between types:

run this code

#include <iostream>
#include <chrono>
 
int main()
{
    typedef std::chrono::duration<int, std::ratio<1, 100000000>> shakes;
    typedef std::chrono::duration<int, std::centi> jiffies;
    typedef std::chrono::duration<float, std::ratio<12096,10000>> microfortnights;
    typedef std::chrono::duration<float, std::ratio<3155,1000>> nanocenturies;
 
    std::chrono::seconds sec(1);
 
    std::cout << "1 second is:\n";
 
    std::cout << std::chrono::duration_cast<shakes>(sec).count()
              << " shakes\n";
    std::cout << std::chrono::duration_cast<jiffies>(sec).count()
              << " jiffies\n";
    std::cout << std::chrono::duration_cast<microfortnights>(sec).count()
              << " microfortnights\n";
    std::cout << std::chrono::duration_cast<nanocenturies>(sec).count()
              << " nanocenturies\n";
}

Output:

1 second is:
100000000 shakes
100 jiffies
0.82672 microfortnights
0.316957 nanocenturies