Struct task_scope::cancelable::Cancelable

#[must_use = "do nothing unless polled"]
pub struct Cancelable<T> { /* fields omitted */ }

A cancelable wrapper for asynchronous operations.

This wrapper is created by cancelable function.

Methods

impl<T> Cancelable<T>

pub fn poll_canceled(
    self: Pin<&mut Self>,
    cx: &mut Context
) -> Poll<Option<Canceled>>

Polls whether the task is canceled.

Returns

Returns Ready(Some(reason)) if the task is canceled. Returns Ready(None) if the context doesn't support cancellation.

pub fn inner(self: Pin<&mut Self>) -> Pin<&mut T>

retrieve the inner value.

Trait Implementations

impl<T> AsyncRead for Cancelable<T> where
    T: AsyncRead, 

fn poll_read(
    self: Pin<&mut Self>,
    cx: &mut Context,
    buf: &mut [u8]
) -> Poll<Result<usize>>

Attempt to read from the AsyncRead into buf.

fn poll_read_vectored(
    self: Pin<&mut Self>,
    cx: &mut Context,
    bufs: &mut [IoSliceMut]
) -> Poll<Result<usize, Error>>

Attempt to read from the AsyncRead into bufs using vectored IO operations.

impl<T> AsyncRead for Cancelable<T> where
    T: AsyncRead, 

fn poll_read(
    self: Pin<&mut Self>,
    cx: &mut Context,
    buf: &mut [u8]
) -> Poll<Result<usize>>

Attempt to read from the AsyncRead into buf.

unsafe fn prepare_uninitialized_buffer(
    &self,
    buf: &mut [MaybeUninit<u8>]
) -> bool

Prepares an uninitialized buffer to be safe to pass to read. Returns true if the supplied buffer was zeroed out.

fn poll_read_buf<B: BufMut>(
    self: Pin<&mut Self>,
    cx: &mut Context,
    buf: &mut B
) -> Poll<Result<usize>>

Pull some bytes from this source into the specified BufMut, returning how many bytes were read.

impl<T> AsyncWrite for Cancelable<T> where
    T: AsyncWrite, 

fn poll_write(
    self: Pin<&mut Self>,
    cx: &mut Context,
    buf: &[u8]
) -> Poll<Result<usize>>

Attempt to write bytes from buf into the object.

fn poll_flush(self: Pin<&mut Self>, cx: &mut Context) -> Poll<Result<()>>

Attempt to flush the object, ensuring that any buffered data reach their destination.

fn poll_close(self: Pin<&mut Self>, cx: &mut Context) -> Poll<Result<()>>

Attempt to close the object.

fn poll_write_vectored(
    self: Pin<&mut Self>,
    cx: &mut Context,
    bufs: &[IoSlice]
) -> Poll<Result<usize, Error>>

Attempt to write bytes from bufs into the object using vectored IO operations.

impl<T> AsyncWrite for Cancelable<T> where
    T: AsyncWrite, 

fn poll_write(
    self: Pin<&mut Self>,
    cx: &mut Context,
    buf: &[u8]
) -> Poll<Result<usize>>

Attempt to write bytes from buf into the object.

fn poll_flush(self: Pin<&mut Self>, cx: &mut Context) -> Poll<Result<()>>

Attempt to flush the object, ensuring that any buffered data reach their destination.

fn poll_shutdown(self: Pin<&mut Self>, cx: &mut Context) -> Poll<Result<()>>

Initiates or attempts to shut down this writer, returning success when the I/O connection has completely shut down.

fn poll_write_buf<B: Buf>(
    self: Pin<&mut Self>,
    cx: &mut Context,
    buf: &mut B
) -> Poll<Result<usize>>

Write a Buf into this value, returning how many bytes were written.

impl<T> FusedFuture for Cancelable<T> where
    T: FusedFuture, 

fn is_terminated(&self) -> bool

Returns true if the underlying future should no longer be polled.

impl<T> FusedStream for Cancelable<T> where
    T: FusedStream, 

fn is_terminated(&self) -> bool

Returns true if the stream should no longer be polled.

impl<T> Future for Cancelable<T> where
    T: Future, 

type Output = Result<T::Output, Canceled>

The type of value produced on completion.

fn poll(self: Pin<&mut Self>, cx: &mut Context) -> Poll<Self::Output>

Attempt to resolve the future to a final value, registering the current task for wakeup if the value is not yet available.

impl<T> Stream for Cancelable<T> where
    T: Stream, 

type Item = Result<T::Item, Canceled>

Values yielded by the stream.

fn poll_next(self: Pin<&mut Self>, cx: &mut Context) -> Poll<Option<Self::Item>>

Attempt to pull out the next value of this stream, registering the current task for wakeup if the value is not yet available, and returning None if the stream is exhausted.

fn size_hint(&self) -> (usize, Option<usize>)

Returns the bounds on the remaining length of the stream.

impl<'pin, T> Unpin for Cancelable<T> where
    __Cancelable<'pin, T>: Unpin,