class template

std::chrono::duration

template <class Rep, class Period = ratio<1> >class duration;

Duration

A duration object expresses a time span by means of a count and a period.

Internally, the object stores the count as an object of member type rep (an alias of the first template parameter, Rep), which can be retrieved by calling member function count.

This count is expresed in terms of periods. The length of a period is integrated in the type (on compile time) by its second template parameter (Period), which is a ratio type that expresses the number (or fraction) of seconds that elapse in each period.

Template parameters

Rep: An arithmetic type, or a class emulating an arithmetic type, to be used as the type for the internal count.
Period: A ratio type that represents the period in seconds.

Template instantiations

The following convenience typedefs of instantiations of duration are also defined in this namespace:

type	Representation	Period
`hours`	signed integral type of at least 23 bits	`ratio<3600,1>`
`minutes`	signed integral type of at least 29 bits	`ratio<60,1>`
`seconds`	signed integral type of at least 35 bits	`ratio<1,1>`
`milliseconds`	signed integral type of at least 45 bits	`ratio<1,1000>`
`microseconds`	signed integral type of at least 55 bits	`ratio<1,1000000>`
`nanoseconds`	signed integral type of at least 64 bits	`ratio<1,1000000000>`

Member types

The following aliases are member types of duration. They are widely used as parameter and return types by member functions:

member type	definition	notes
`rep`	The first template parameter (`Rep`)	Representation type used as the type for the internal count object.
`period`	The second template parameter (`Period`)	The ratio type that represents a period in seconds.

Member functions

(constructor): Construct duration object (public member function)

(destructor): Destroy duration (public member function)

count: Get count (public member function)

static member functions

zero: Zero value (public static member function)

min: Duration minimum value (public static member function)

max: Duration maximum value (public static member function)

Non-member functions

operators: Duration operators (function template)

classes

functions

class typedefs

member functions

static member functions

std::chrono::duration

Template parameters

Template instantiations

Member types

Member functions

static member functions

Non-member functions

See also