CesiumAsync::Future< T > Class Template Reference

A value that will be available in the future, as produced by AsyncSystem. More...

#include <CesiumAsync/Future.h>

Public Member Functions
	Future (Future< T > &&rhs) noexcept
	Move constructor.
Future< T > &	operator= (Future< T > &&rhs) noexcept
	Future (const Future< T > &rhs)=delete
Future< T > &	operator= (const Future< T > &rhs)=delete
template<typename Func >
CesiumImpl::ContinuationFutureType_t< Func, T >	thenInWorkerThread (Func &&f) &&
	Registers a continuation function to be invoked in a worker thread when this Future resolves, and invalidates this Future. More...
template<typename Func >
CesiumImpl::ContinuationFutureType_t< Func, T >	thenInMainThread (Func &&f) &&
	Registers a continuation function to be invoked in the main thread when this Future resolves, and invalidates this Future. More...
template<typename Func >
CesiumImpl::ContinuationFutureType_t< Func, T >	thenImmediately (Func &&f) &&
	Registers a continuation function to be invoked immediately in whichever thread causes the Future to be resolved, and invalidates this Future. More...
template<typename Func >
CesiumImpl::ContinuationFutureType_t< Func, T >	thenInThreadPool (const ThreadPool &threadPool, Func &&f) &&
	Registers a continuation function to be invoked in a thread pool when this Future resolves, and invalidates this Future. More...
template<typename Func >
Future< T >	catchInMainThread (Func &&f) &&
	Registers a continuation function to be invoked in the main thread when this Future rejects, and invalidates this Future. More...
template<typename Func >
Future< T >	catchImmediately (Func &&f) &&
	Registers a continuation function to be invoked immediately, and invalidates this Future. More...
template<typename... TPassThrough>
Future< std::tuple< TPassThrough..., T > >	thenPassThrough (TPassThrough &&... values) &&
	Passes through one or more additional values to the next continuation. More...
T	wait ()
	Waits for the future to resolve or reject and returns the result. More...
T	waitInMainThread ()
	Waits for this future to resolve or reject in the main thread while also processing main-thread tasks. More...
bool	isReady () const
	Determines if this future is already resolved or rejected. More...
SharedFuture< T >	share () &&
	Creates a version of this future that can be shared, meaning that its value may be accessed multiple times and multiple continuations may be attached to it. More...

Friends
class	AsyncSystem
template<typename R >
struct	CesiumImpl::ParameterizedTaskUnwrapper
struct	CesiumImpl::TaskUnwrapper
template<typename R >
class	SharedFuture
template<typename R >
class	Promise

Detailed Description

template<typename T>
class CesiumAsync::Future< T >

A value that will be available in the future, as produced by AsyncSystem.

Template Parameters

T	The type of the value.

Definition at line 29 of file Future.h.

Member Function Documentation

catchImmediately()

template<typename T >

template<typename Func >

Future<T> CesiumAsync::Future< T >::catchImmediately ( Func &&  f ) &&

inline

Registers a continuation function to be invoked immediately, and invalidates this Future.

When this Future is rejected, the continuation function will be invoked in whatever thread does the rejection. Similarly, if the Future is already rejected when catchImmediately is called, the continuation function will be invoked immediately before this method returns.

If the function itself returns a Future, the function will not be considered complete until that returned Future also resolves.

Any then continuations chained after this one will be invoked with the return value of the catch callback.

Template Parameters

Func	The type of the function.

Parameters

f	The function.

Returns

A future that resolves after the supplied function completes.

Definition at line 198 of file Future.h.

catchInMainThread()

template<typename T >

template<typename Func >

Future<T> CesiumAsync::Future< T >::catchInMainThread ( Func &&  f ) &&

inline

Registers a continuation function to be invoked in the main thread when this Future rejects, and invalidates this Future.

If this Future is rejected from the main thread, the continuation function will be invoked immediately rather than queued for later execution in the main thread. Similarly, if the Future is already rejected when catchInMainThread is called from the main thread, the continuation function will be invoked immediately before this method returns.

If the function itself returns a Future, the function will not be considered complete until that returned Future also resolves.

Any then continuations chained after this one will be invoked with the return value of the catch callback.

Template Parameters

Func	The type of the function.

Parameters

f	The function.

Returns

A future that resolves after the supplied function completes.

Definition at line 173 of file Future.h.

isReady()

template<typename T >

bool CesiumAsync::Future< T >::isReady ( ) const

inline

Determines if this future is already resolved or rejected.

If this method returns true, it is guaranteed that wait will not block but will instead immediately return a value or throw an exception.

Returns

True if the future is already resolved or rejected and wait will not block; otherwise, false.

Definition at line 272 of file Future.h.

share()

template<typename T >

SharedFuture<T> CesiumAsync::Future< T >::share ( ) &&

inline

Creates a version of this future that can be shared, meaning that its value may be accessed multiple times and multiple continuations may be attached to it.

Calling this method invalidates the original Future.

Returns

The SharedFuture.

Definition at line 283 of file Future.h.

thenImmediately()

template<typename T >

template<typename Func >

CesiumImpl::ContinuationFutureType_t<Func, T> CesiumAsync::Future< T >::thenImmediately ( Func &&  f ) &&

inline

Registers a continuation function to be invoked immediately in whichever thread causes the Future to be resolved, and invalidates this Future.

If the Future is already resolved, the supplied function will be called immediately in the calling thread and this method will not return until that function does.

If the function itself returns a Future, the function will not be considered complete until that returned Future also resolves.

Template Parameters

Func	The type of the function.

Parameters

f	The function.

Returns

A future that resolves after the supplied function completes.

Definition at line 117 of file Future.h.

thenInMainThread()

template<typename T >

template<typename Func >

CesiumImpl::ContinuationFutureType_t<Func, T> CesiumAsync::Future< T >::thenInMainThread ( Func &&  f ) &&

inline

Registers a continuation function to be invoked in the main thread when this Future resolves, and invalidates this Future.

If this Future is resolved from the main thread, the continuation function will be invoked immediately rather than queued for later execution in the main thread. Similarly, if the Future is already resolved when thenInMainThread is called from the main thread, the continuation function will be invoked immediately before this method returns.

If the function itself returns a Future, the function will not be considered complete until that returned Future also resolves.

Template Parameters

Func	The type of the function.

Parameters

f	The function.

Returns

A future that resolves after the supplied function completes.

Definition at line 93 of file Future.h.

thenInThreadPool()

template<typename T >

template<typename Func >

CesiumImpl::ContinuationFutureType_t<Func, T> CesiumAsync::Future< T >::thenInThreadPool ( const ThreadPool &  threadPool, Func &&  f  ) &&

inline

Registers a continuation function to be invoked in a thread pool when this Future resolves, and invalidates this Future.

If the function itself returns a Future, the function will not be considered complete until that returned Future also resolves.

If this Future is resolved from a thread pool thread, the continuation function will be invoked immediately rather than in a separate task. Similarly, if the Future is already resolved when thenInThreadPool is called from a designated thread pool thread, the continuation function will be invoked immediately before this method returns.

Template Parameters

Func	The type of the function.

Parameters

f	The function.

Returns

A future that resolves after the supplied function completes.

Definition at line 145 of file Future.h.

thenInWorkerThread()

template<typename T >

template<typename Func >

CesiumImpl::ContinuationFutureType_t<Func, T> CesiumAsync::Future< T >::thenInWorkerThread ( Func &&  f ) &&

inline

Registers a continuation function to be invoked in a worker thread when this Future resolves, and invalidates this Future.

If the function itself returns a Future, the function will not be considered complete until that returned Future also resolves.

If this Future is resolved from a designated worker thread, the continuation function will be invoked immediately rather than in a separate task. Similarly, if the Future is already resolved when thenInWorkerThread is called from a designated worker thread, the continuation function will be invoked immediately before this method returns.

Template Parameters

Func	The type of the function.

Parameters

f	The function.

Returns

A future that resolves after the supplied function completes.

Definition at line 67 of file Future.h.

thenPassThrough()

template<typename T >

template<typename... TPassThrough>

Future<std::tuple<TPassThrough..., T> > CesiumAsync::Future< T >::thenPassThrough ( TPassThrough &&...  values ) &&

inline

Passes through one or more additional values to the next continuation.

The next continuation will receive a tuple with each of the provided values, followed by the result of the current Future.

Template Parameters

TPassThrough

The types to pass through to the next continuation.

Parameters

value

The values to pass through to the next continuation.

Returns

A new Future that resolves to a tuple with the pass-through values, followed by the result of the last Future.

Definition at line 218 of file Future.h.

wait()

template<typename T >

T CesiumAsync::Future< T >::wait ( )

inline

Waits for the future to resolve or reject and returns the result.

This method must not be called from the main thread, the one that calls AsyncSystem::dispatchMainThreadTasks. Doing so can lead to a deadlock because the main thread tasks will never complete while this method is blocking the main thread.

To wait in the main thread, use waitInMainThread instead.

Returns

The value if the future resolves successfully.

Exceptions

An	exception if the future rejected.

Definition at line 241 of file Future.h.

waitInMainThread()

template<typename T >

T CesiumAsync::Future< T >::waitInMainThread ( )

inline

Waits for this future to resolve or reject in the main thread while also processing main-thread tasks.

This method must be called from the main thread.

The function does not return until Future::isReady returns true. In the meantime, main-thread tasks are processed as necessary. This method does not spin wait; it suspends the calling thread by waiting on a condition variable when there is no work to do.

Returns

The value if the future resolves successfully.

Exceptions

An	exception if the future rejected.

Definition at line 257 of file Future.h.

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The documentation for this class was generated from the following file:

• /home/runner/work/cesium-native/cesium-native/CesiumAsync/include/CesiumAsync/Future.h