Google Cloud C++ Client  1.32.1
C++ Client Library for Google Cloud Platform
Public Types | Public Member Functions | Friends | List of all members
google::cloud::v1::future< void > Class Referencefinal

Implement ISO/IEC TS 19571:2016 future for void. More...

#include <google/cloud/future_void.h>

Public Types

using shared_state_type = typename internal::future_base< void >::shared_state_type
 

Public Member Functions

 future () noexcept
 
 future (future< future< void >> &&rhs) noexcept(false)
 Creates a new future that unwraps rhs. More...
 
void get ()
 Waits until the shared state becomes ready, then retrieves the value stored in the shared state. More...
 
template<typename F >
internal::then_helper< F, void >::future_t then (F &&func)
 Attach a continuation to the future. More...
 
 future (std::shared_ptr< shared_state_type > state)
 

Friends

template<typename U >
class future
 

Detailed Description

Implement ISO/IEC TS 19571:2016 future for void.

Definition at line 36 of file future_void.h.

Member Typedef Documentation

◆ shared_state_type

using google::cloud::v1::future< void >::shared_state_type = typename internal::future_base<void>::shared_state_type

Definition at line 38 of file future_void.h.

Constructor & Destructor Documentation

◆ future() [1/3]

google::cloud::v1::future< void >::future ( )
inlinenoexcept

Definition at line 43 of file future_void.h.

◆ future() [2/3]

google::cloud::v1::future< void >::future ( future< future< void >> &&  rhs)
noexcept

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.

Note
The technical specification requires this to be a noexcept constructor I (coryan) believe this is a defect in the technical specification, as this creates a new shared state: shared states are dynamically allocated, and the allocator (which might be the default operator new) may raise.

◆ future() [3/3]

google::cloud::v1::future< void >::future ( std::shared_ptr< shared_state_type state)
inlineexplicit

Definition at line 109 of file future_void.h.

Member Function Documentation

◆ get()

void google::cloud::v1::future< void >::get ( )
inline

Waits until the shared state becomes ready, then retrieves the value stored in the shared state.

Exceptions
anyexceptions stored in the shared state.
std::future_errorwith std::no_state if the future does not have a shared state.

Definition at line 71 of file future_void.h.

◆ then()

template<typename F >
internal::then_helper<F, void>::future_t google::cloud::v1::future< void >::then ( F &&  func)
inline

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.

Returns
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.
Parameters
funca Callable to be invoked when the future is ready. The function might be called immediately, e.g., if the future is ready.

Side effects: valid() == false if the operation is successful.

Definition at line 102 of file future_void.h.

Friends And Related Function Documentation

◆ future

template<typename U >
friend class future
friend

Definition at line 124 of file future_void.h.