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wpi::uv::AsyncFunction< R(T...)> Class Template Referencefinal

Function async handle. More...

#include <AsyncFunction.h>

Inheritance diagram for wpi::uv::AsyncFunction< R(T...)>:
wpi::uv::HandleImpl< AsyncFunction< R(T...)>, uv_async_t > wpi::uv::Handle

Public Member Functions

 AsyncFunction (const std::shared_ptr< Loop > &loop, std::function< void(promise< R >, T...)> func, const private_init &)
 
template<typename... U>
future< R > Call (U &&...u)
 Wakeup the event loop, call the async function, and return a future for the result. More...
 
template<typename... U>
future< R > operator() (U &&...u)
 
- Public Member Functions inherited from wpi::uv::HandleImpl< AsyncFunction< R(T...)>, uv_async_t >
std::shared_ptr< AsyncFunction
< R(T...)> > 
shared_from_this ()
 
std::shared_ptr< const
AsyncFunction< R(T...)> > 
shared_from_this () const
 
uv_async_tGetRaw () const noexcept
 Get the underlying handle data structure. More...
 
- Public Member Functions inherited from wpi::uv::Handle
 Handle (const Handle &)=delete
 
 Handle (Handle &&)=delete
 
Handleoperator= (const Handle &)=delete
 
Handleoperator= (Handle &&)=delete
 
Type GetType () const noexcept
 Get the type of the handle. More...
 
StringRef GetTypeName () const noexcept
 Get the name of the type of the handle. More...
 
std::shared_ptr< LoopGetLoop () const noexcept
 Get the loop where this handle runs. More...
 
LoopGetLoopRef () const noexcept
 Get the loop where this handle runs. More...
 
bool IsActive () const noexcept
 Check if the handle is active. More...
 
bool IsClosing () const noexcept
 Check if a handle is closing or closed. More...
 
void Close () noexcept
 Request handle to be closed. More...
 
void Reference () noexcept
 Reference the given handle. More...
 
void Unreference () noexcept
 Unreference the given handle. More...
 
bool HasReference () const noexcept
 Check if the given handle is referenced. More...
 
size_t RawSize () const noexcept
 Return the size of the underlying handle type. More...
 
uv_handle_tGetRawHandle () const noexcept
 Get the underlying handle data structure. More...
 
void SetBufferAllocator (std::function< Buffer(size_t)> alloc, std::function< void(Buffer &)> dealloc)
 Set the functions used for allocating and releasing buffers. More...
 
void FreeBuf (Buffer &buf) const noexcept
 Free a buffer. More...
 
template<typename T = void>
std::shared_ptr< T > GetData () const
 Gets user-defined data. More...
 
void SetData (std::shared_ptr< void > data)
 Sets user-defined data. More...
 
void ReportError (int err)
 Report an error. More...
 

Static Public Member Functions

static std::shared_ptr
< AsyncFunction
Create (Loop &loop, std::function< void(promise< R >, T...)> func=nullptr)
 Create an async handle. More...
 
static std::shared_ptr
< AsyncFunction
Create (const std::shared_ptr< Loop > &loop, std::function< void(promise< R >, T...)> func=nullptr)
 Create an async handle. More...
 

Public Attributes

std::function< void(promise< R >
, T...)> 
wakeup
 Function called (on event loop thread) when the async is called.
 
- Public Attributes inherited from wpi::uv::Handle
sig::Signal< Errorerror
 Error signal.
 
sig::Signal closed
 Closed signal.
 

Additional Inherited Members

- Public Types inherited from wpi::uv::Handle
using Type = uv_handle_type
 
- Protected Member Functions inherited from wpi::uv::Handle
 Handle (uv_handle_t *uv_handle)
 
void Keep () noexcept
 
void Release () noexcept
 
void ForceClosed () noexcept
 
template<typename F , typename... Args>
bool Invoke (F &&f, Args &&...args)
 
- Static Protected Member Functions inherited from wpi::uv::Handle
static void AllocBuf (uv_handle_t *handle, size_t size, uv_buf_t *buf)
 
static void DefaultFreeBuf (Buffer &buf)
 

Detailed Description

template<typename R, typename... T>
class wpi::uv::AsyncFunction< R(T...)>

Function async handle.

Async handles allow the user to "wakeup" the event loop and have a function called from another thread that returns a result to the calling thread.

Member Function Documentation

template<typename R , typename... T>
template<typename... U>
future<R> wpi::uv::AsyncFunction< R(T...)>::Call ( U &&...  u)
inline

Wakeup the event loop, call the async function, and return a future for the result.

It’s safe to call this function from any thread including the loop thread. The async function will be called on the loop thread.

The future will return a default-constructed result if this handle is destroyed while waiting for a result.

template<typename R , typename... T>
static std::shared_ptr<AsyncFunction> wpi::uv::AsyncFunction< R(T...)>::Create ( Loop loop,
std::function< void(promise< R >, T...)>  func = nullptr 
)
inlinestatic

Create an async handle.

Parameters
loopLoop object where this handle runs.
funcwakeup function to be called (sets wakeup value); the function needs to return void, and its first parameter is the promise for the result. If no value is set on the promise by the wakeup function, a default-constructed value is "returned".
template<typename R , typename... T>
static std::shared_ptr<AsyncFunction> wpi::uv::AsyncFunction< R(T...)>::Create ( const std::shared_ptr< Loop > &  loop,
std::function< void(promise< R >, T...)>  func = nullptr 
)
inlinestatic

Create an async handle.

Parameters
loopLoop object where this handle runs.
funcwakeup function to be called (sets wakeup value); the function needs to return void, and its first parameter is the promise for the result. If no value is set on the promise by the wakeup function, a default-constructed value is "returned".

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