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< void > > &&
future(future< T > &&)
Creates a future from a future whose result type is convertible to this future's result type.
Parameters
Name
Description
rhs
future< T > &&
class T
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
void
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
future< >
future<T> where T is std::result_of_t<F, R> (basically). If T matches future<U> then it returns future<U>. The returned future will contain the result of func.
Type Aliases
shared_state_type
Alias Of: typename internal::future_base< internal::FutureVoid >::shared_state_type
[[["Easy to understand","easyToUnderstand","thumb-up"],["Solved my problem","solvedMyProblem","thumb-up"],["Other","otherUp","thumb-up"]],[["Missing the information I need","missingTheInformationINeed","thumb-down"],["Too complicated / too many steps","tooComplicatedTooManySteps","thumb-down"],["Out of date","outOfDate","thumb-down"],["Samples / code issue","samplesCodeIssue","thumb-down"],["Other","otherDown","thumb-down"]],["Last updated 2025-08-07 UTC."],[[["This document provides the documentation for different versions of a `future\u003cvoid\u003e` class, ranging from version 2.10.1 up to the latest release candidate 2.37.0-rc."],["The `future\u003cvoid\u003e` class specializes the ISO/IEC TS 19571:2016 future for void, and includes multiple constructors to create futures from other futures or shared states."],["The `get()` function is used to wait until the shared state of the future is ready, and then it retrieves the stored value, potentially throwing exceptions if any are present in the shared state."],["The `then(F &&)` function allows for attaching a continuation (callable function) that will be invoked when the future is ready, returning a new future that wraps the return type of the provided function."],["The provided documentation include the parameters and return types for the given constructors and methods for various versions."]]],[]]
