Struct futures_util::stream::Once[−][src]

#[must_use = "streams do nothing unless polled"]
pub struct Once<Fut> { /* fields omitted */ }
Expand description

A stream which emits single element and then EOF.

Trait Implementations

impl<Fut: Debug> Debug for Once<Fut>[src]

fn fmt(&self, f: &mut Formatter<'_>) -> Result[src]

Formats the value using the given formatter. Read more

impl<Fut: Future> FusedStream for Once<Fut>[src]

fn is_terminated(&self) -> bool[src]

Returns true if the stream should no longer be polled.

impl<Fut: Future> Stream for Once<Fut>[src]

type Item = Fut::Output

Values yielded by the stream.

fn poll_next(
    self: Pin<&mut Self>,
    cx: &mut Context<'_>
) -> Poll<Option<Self::Item>>[src]

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. Read more

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

Returns the bounds on the remaining length of the stream. Read more

impl<'__pin, Fut> Unpin for Once<Fut> where
    __Origin<'__pin, Fut>: Unpin, [src]

Auto Trait Implementations

impl<Fut> RefUnwindSafe for Once<Fut> where
    Fut: RefUnwindSafe, 

impl<Fut> Send for Once<Fut> where
    Fut: Send, 

impl<Fut> Sync for Once<Fut> where
    Fut: Sync, 

impl<Fut> UnwindSafe for Once<Fut> where
    Fut: UnwindSafe, 

Blanket Implementations

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

pub fn type_id(&self) -> TypeId[src]

Gets the TypeId of self. Read more

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

pub fn borrow(&self) -> &T[src]

Immutably borrows from an owned value. Read more

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

pub fn borrow_mut(&mut self) -> &mut T[src]

Mutably borrows from an owned value. Read more

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

pub fn from(t: T) -> T[src]

Performs the conversion.

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

pub fn into(self) -> U[src]

Performs the conversion.

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.

pub fn try_from(value: U) -> Result<T, <T as TryFrom<U>>::Error>[src]

Performs the conversion.

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.

pub fn try_into(self) -> Result<U, <U as TryFrom<T>>::Error>[src]

Performs the conversion.

impl<S, T, E> TryStream for S where
    S: Stream<Item = Result<T, E>> + ?Sized, [src]

type Ok = T

The type of successful values yielded by this future

type Error = E

The type of failures yielded by this future

pub fn try_poll_next(
    self: Pin<&mut S>,
    cx: &mut Context<'_>
) -> Poll<Option<Result<<S as TryStream>::Ok, <S as TryStream>::Error>>>[src]

Poll this TryStream as if it were a Stream. Read more