Implement ISO/IEC TS 19571:2016 future<T>.
Constructors
future()
future(future< future< T > > &&)
Creates a new future that unwraps rhs.
This constructor creates a new shared state that becomes satisfied when both rhs and rhs.get() become satisfied. If rhs is satisfied, but rhs.get() returns an invalid future then the newly created future becomes satisfied with a std::future_error exception, and the exception error code is std::future_errc::broken_promise.
| Parameter | |
|---|---|
| Name | Description |
rhs |
future< future< T > > &&
|
future(future< U > &&)
Creates a future from a future whose result type is convertible to this future's result type.
| Parameters | |
|---|---|
| Name | Description |
rhs |
future< U > &&
|
class U |
|
typename Enable |
|
future(std::shared_ptr< shared_state_type >)
| Parameter | |
|---|---|
| Name | Description |
state |
std::shared_ptr< shared_state_type >
|
Functions
get()
Waits until the shared state becomes ready, then retrieves the value stored in the shared state.
| Exceptions | |
|---|---|
| Type | Description |
... | any exceptions stored in the shared state. |
std::future_error | with std::no_state if the future does not have a shared state. |
| Returns | |
|---|---|
| Type | Description |
T | |
then(F &&)
Attach a continuation to the future.
Attach a callable func to be invoked when the future is ready. The return type is a future wrapping the return type of func.
Side effects: valid() == false if the operation is successful.
| Parameters | |
|---|---|
| Name | Description |
func |
F &&
a Callable to be invoked when the future is ready. The function might be called immediately, e.g., if the future is ready. |
typename F |
|
| Returns | |
|---|---|
| Type | Description |
internal::then_helper< F, T >::future_t |
|
Type Aliases
shared_state_type
typename internal::future_base< T >::shared_state_type