TPromise | Unreal Engine 5.7 Documentation

TPromise Template for promises.


Name	TPromise
Type	class
Header File	/Engine/Source/Runtime/Core/Public/Async/Future.h
Include Path	#include "Async/Future.h"

Syntax

template<typename ResultType>  
class TPromise

Name	Remarks	Include Path
TPromise ()	Default constructor (creates a new shared state).	Async/Future.h
TPromise ( TUniqueFunction< void()>&& CompletionCallback )	Create and initialize a new instance with a callback.	Async/Future.h
TPromise ( TPromise&& Other )	Movable-only.	Async/Future.h
TPromise ( const TPromise& Other )		Async/Future.h

Name	Remarks	Include Path	Unreal Specifiers
~TPromise()	Destructor.	Async/Future.h

Name	Type	Remarks	Include Path
SetType	std::conditional_t< std::is_void_v< ResultType >, int, ResultType >	This is necessary because we can't form references to void for the parameter of Set().	Async/Future.h
StateType	TFutureState< ResultType >		Async/Future.h

Name	Type	Remarks	Include Path	Unreal Specifiers
bFutureRetrieved	bool	Whether a future has already been retrieved from this promise.	Async/Future.h
State	TSharedPtr< StateType >	Holds the shared state object.	Async/Future.h

Name	Remarks	Include Path
void EmplaceValue ( ArgTypes&&... Args )	Sets the promised result.	Async/Future.h
TFuture< ResultType > GetFuture()	Gets a TFuture object associated with the shared state of this promise.	Async/Future.h
void SetValue ()		Async/Future.h
void SetValue ( const SetType& Result )	Sets the promised result.	Async/Future.h
void SetValue ( SetType&& Result )		Async/Future.h

Name	Remarks	Include Path	Unreal Specifiers
const TSharedPtr< StateType > & GetState()	Gets the shared state object.	Async/Future.h

Name	Remarks	Include Path	Unreal Specifiers
TPromise & operator= ( TPromise&& Other )		Async/Future.h
TPromise & operator= ( const TPromise& Other )		Async/Future.h