completion_future Class

Represents a future corresponding to a C++ AMP asynchronous operation.

Syntax

class completion_future;

Members

Public Constructors

Public Methods

Public Operators

Inheritance Hierarchy

completion_future

Requirements

Header: amprt.h

Namespace: concurrency

completion_future

Initializes a new instance of the completion_future class.

Syntax

completion_future();

completion_future(
    const completion_future& _Other );

completion_future(
    completion_future&& _Other );

Parameters

_Other
The completion_future object to copy or move.

Overloads List

get

Waits until the associated asynchronous operation completes. Throws the stored exception if one was encountered during the asynchronous operation.

Syntax

void get() const;

operator std::shared_future<void>

Implicitly converts the completion_future object to an std::shared_future object.

Syntax

operator std::shared_future<void>() const;

Return Value

An std::shared_future object.

operator=

Copies the contents of the specified completion_future object into this one.

Syntax

completion_future&  operator= (const completion_future& _Other );
completion_future&  operator= (completion_future&& _Other );

Parameters

_Other
The object to copy from.

Return Value

A reference to this completion_future object.

Overloads List

then

Chains a callback function object to the completion_future object to be executed when the associated asynchronous operation finishes execution.

Syntax

template <typename _Functor>
void then(const _Functor & _Func ) const;

Parameters

_Functor
The callback functor.

_Func
The callback function object.

to_task

Returns a task object corresponding to the associated asynchronous operation.

Syntax

concurrency::task<void> to_task() const;

Return Value

A task object corresponding to the associated asynchronous operation.

valid

Gets a Boolean value that indicates whether the object is associated with an asynchronous operation.

Syntax

bool valid() const;

Return Value

true if the object is associated with an asynchronous operation; otherwise, false.

wait

Blocks until the associated asynchronous operation completes.

Syntax

void wait() const;

wait_for

Blocks until the associated asynchronous operation completes or the time that's specified by _Rel_time has elapsed.

Syntax

template <
    class _Rep,
    class _Period
>
std::future_status::future_status wait_for(
    const std::chrono::duration< _Rep, _Period>& _Rel_time ) const;

Parameters

_Rep
An arithmetic type that represents the number of ticks.

_Period
A std::ratio that represents the number of seconds that elapse per tick.

_Rel_time
The maximum amount of time to wait for the operation to complete.

Return Value

Returns:

• std::future_status::deferred if the associated asynchronous operation is not running.

• std::future_status::ready if the associated asynchronous operation is finished.

• std::future_status::timeout if the specified time period has elapsed.

wait_until

Blocks until the associated asynchronous operation completes or until the current time exceeds the value specified by _Abs_time.

Syntax

template <
    class _Clock,
    class _Duration
>
std::future_status::future_status wait_until(
    const std::chrono::time_point< _Clock, _Duration>& _Abs_time ) const;

Parameters

_Clock
The clock on which this time point is measured.

_Duration
The time interval since the start of _Clock's epoch, after which the function will time out.

_Abs_time
The point in time after which the function will time out.

Return Value

Returns:

1. std::future_status::deferred if the associated asynchronous operation is not running.

2. std::future_status::ready if the associated asynchronous operation is finished.

3. std::future_status::timeout if the time period specified has elapsed.

~completion_future

Destroys the completion_future object.

Syntax

~completion_future();

See also

Concurrency Namespace (C++ AMP)