Struct futures_util::io::Take[][src]

#[must_use = "readers do nothing unless you `.await` or poll them"]pub struct Take<R> { /* fields omitted */ }

Reader for the take method.

Implementations

impl<R: AsyncRead> Take<R>[src]

pub fn limit(&self) -> u64[src]

Returns the remaining number of bytes that can be read before this instance will return EOF.

Note

This instance may reach EOF after reading fewer bytes than indicated by this method if the underlying AsyncRead instance reaches EOF.

Examples

use futures::io::{AsyncReadExt, Cursor};

let reader = Cursor::new(&b"12345678"[..]);
let mut buffer = [0; 2];

let mut take = reader.take(4);
let n = take.read(&mut buffer).await?;

assert_eq!(take.limit(), 2);

pub fn set_limit(&mut self, limit: u64)[src]

Sets the number of bytes that can be read before this instance will return EOF. This is the same as constructing a new Take instance, so the amount of bytes read and the previous limit value don’t matter when calling this method.

Examples

use futures::io::{AsyncReadExt, Cursor};

let reader = Cursor::new(&b"12345678"[..]);
let mut buffer = [0; 4];

let mut take = reader.take(4);
let n = take.read(&mut buffer).await?;

assert_eq!(n, 4);
assert_eq!(take.limit(), 0);

take.set_limit(10);
let n = take.read(&mut buffer).await?;
assert_eq!(n, 4);

pub fn get_ref(&self) -> &R[src]

Acquires a reference to the underlying sink or stream that this combinator is pulling from.

pub fn get_mut(&mut self) -> &mut R[src]

Acquires a mutable reference to the underlying sink or stream that this combinator is pulling from.

Note that care must be taken to avoid tampering with the state of the sink or stream which may otherwise confuse this combinator.

pub fn get_pin_mut(self: Pin<&mut Self>) -> Pin<&mut R>

Notable traits for Pin<P>

impl<P> Future for Pin<P> where
    P: Unpin + DerefMut,
    <P as Deref>::Target: Future
type Output = <<P as Deref>::Target as Future>::Output;
[src]

Acquires a pinned mutable reference to the underlying sink or stream that this combinator is pulling from.

Note that care must be taken to avoid tampering with the state of the sink or stream which may otherwise confuse this combinator.

pub fn into_inner(self) -> R[src]

Consumes this combinator, returning the underlying sink or stream.

Note that this may discard intermediate state of this combinator, so care should be taken to avoid losing resources when this is called.

Trait Implementations

impl<R: AsyncBufRead> AsyncBufRead for Take<R>[src]

impl<R: AsyncRead> AsyncRead for Take<R>[src]

impl<R: Debug> Debug for Take<R>[src]

impl<'__pin, R> Unpin for Take<R> where
    __Origin<'__pin, R>: Unpin
[src]

Auto Trait Implementations

impl<R> RefUnwindSafe for Take<R> where
    R: RefUnwindSafe

impl<R> Send for Take<R> where
    R: Send

impl<R> Sync for Take<R> where
    R: Sync

impl<R> UnwindSafe for Take<R> where
    R: UnwindSafe

Blanket Implementations

impl<T> Any for T where
    T: 'static + ?Sized
[src]

impl<R> AsyncBufReadExt for R where
    R: AsyncBufRead + ?Sized
[src]

impl<R> AsyncReadExt for R where
    R: AsyncRead + ?Sized
[src]

impl<T> Borrow<T> for T where
    T: ?Sized
[src]

impl<T> BorrowMut<T> for T where
    T: ?Sized
[src]

impl<T> From<T> for T[src]

impl<T, U> Into<U> for T where
    U: From<T>, 
[src]

impl<T, U> TryFrom<U> for T where
    U: Into<T>, 
[src]

type Error = Infallible

The type returned in the event of a conversion error.

impl<T, U> TryInto<U> for T where
    U: TryFrom<T>, 
[src]

type Error = <U as TryFrom<T>>::Error

The type returned in the event of a conversion error.