Struct tokio::prelude::future::Shared

#[must_use = "futures do nothing unless polled"]
pub struct Shared<F> where
    F: Future,  { /* fields omitted */ }

A future that is cloneable and can be polled in multiple threads. Use Future::shared() method to convert any future into a Shared future.

Methods

impl<F> Shared<F> where
    F: Future, 

pub fn peek(
    &self
) -> Option<Result<SharedItem<<F as Future>::Item>, SharedError<<F as Future>::Error>>>

If any clone of this Shared has completed execution, returns its result immediately without blocking. Otherwise, returns None without triggering the work represented by this Shared.

Trait Implementations

impl<F> Clone for Shared<F> where
    F: Future, 

fn clone(&self) -> Shared<F>

Returns a copy of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl<F> Debug for Shared<F> where
    F: Future + Debug,
    <F as Future>::Item: Debug,
    <F as Future>::Error: Debug, 

fn fmt(&self, fmt: &mut Formatter) -> Result<(), Error>

Formats the value using the given formatter.

impl<F> Drop for Shared<F> where
    F: Future, 

fn drop(&mut self)

Executes the destructor for this type.

impl<F> Future for Shared<F> where
    F: Future, 

type Item = SharedItem<<F as Future>::Item>

The type of value that this future will resolved with if it is successful.

type Error = SharedError<<F as Future>::Error>

The type of error that this future will resolve with if it fails in a normal fashion.

fn poll(
    &mut self
) -> Result<Async<<Shared<F> as Future>::Item>, <Shared<F> as Future>::Error>

Query this future to see if its value has become available, registering interest if it is not.

fn wait(self) -> Result<Self::Item, Self::Error>

Block the current thread until this future is resolved.

fn map<F, U>(self, f: F) -> Map<Self, F> where
    F: FnOnce(Self::Item) -> U, 

Map this future's result to a different type, returning a new future of the resulting type.

fn map_err<F, E>(self, f: F) -> MapErr<Self, F> where
    F: FnOnce(Self::Error) -> E, 

Map this future's error to a different error, returning a new future.

fn from_err<E>(self) -> FromErr<Self, E> where
    E: From<Self::Error>, 

Map this future's error to any error implementing From for this future's Error, returning a new future.

fn then<F, B>(self, f: F) -> Then<Self, B, F> where
    B: IntoFuture,
    F: FnOnce(Result<Self::Item, Self::Error>) -> B, 

Chain on a computation for when a future finished, passing the result of the future to the provided closure f.

fn and_then<F, B>(self, f: F) -> AndThen<Self, B, F> where
    B: IntoFuture<Error = Self::Error>,
    F: FnOnce(Self::Item) -> B, 

Execute another future after this one has resolved successfully.

fn or_else<F, B>(self, f: F) -> OrElse<Self, B, F> where
    B: IntoFuture<Item = Self::Item>,
    F: FnOnce(Self::Error) -> B, 

Execute another future if this one resolves with an error.

fn select<B>(self, other: B) -> Select<Self, <B as IntoFuture>::Future> where
    B: IntoFuture<Item = Self::Item, Error = Self::Error>, 

Waits for either one of two futures to complete.

fn select2<B>(self, other: B) -> Select2<Self, <B as IntoFuture>::Future> where
    B: IntoFuture, 

Waits for either one of two differently-typed futures to complete.

fn join<B>(self, other: B) -> Join<Self, <B as IntoFuture>::Future> where
    B: IntoFuture<Error = Self::Error>, 

Joins the result of two futures, waiting for them both to complete.

fn join3<B, C>(
    self,
    b: B,
    c: C
) -> Join3<Self, <B as IntoFuture>::Future, <C as IntoFuture>::Future> where
    B: IntoFuture<Error = Self::Error>,
    C: IntoFuture<Error = Self::Error>, 

Same as join, but with more futures.

fn join4<B, C, D>(
    self,
    b: B,
    c: C,
    d: D
) -> Join4<Self, <B as IntoFuture>::Future, <C as IntoFuture>::Future, <D as IntoFuture>::Future> where
    B: IntoFuture<Error = Self::Error>,
    C: IntoFuture<Error = Self::Error>,
    D: IntoFuture<Error = Self::Error>, 

Same as join, but with more futures.

fn join5<B, C, D, E>(
    self,
    b: B,
    c: C,
    d: D,
    e: E
) -> Join5<Self, <B as IntoFuture>::Future, <C as IntoFuture>::Future, <D as IntoFuture>::Future, <E as IntoFuture>::Future> where
    B: IntoFuture<Error = Self::Error>,
    C: IntoFuture<Error = Self::Error>,
    D: IntoFuture<Error = Self::Error>,
    E: IntoFuture<Error = Self::Error>, 

Same as join, but with more futures.

fn into_stream(self) -> IntoStream<Self>

Convert this future into a single element stream.

fn flatten(self) -> Flatten<Self> where
    Self::Item: IntoFuture,
    <Self::Item as IntoFuture>::Error: From<Self::Error>, 

Flatten the execution of this future when the successful result of this future is itself another future.

fn flatten_stream(self) -> FlattenStream<Self> where
    Self::Item: Stream,
    <Self::Item as Stream>::Error == Self::Error, 

Flatten the execution of this future when the successful result of this future is a stream.

fn fuse(self) -> Fuse<Self>

Fuse a future such that poll will never again be called once it has completed.

fn inspect<F>(self, f: F) -> Inspect<Self, F> where
    F: FnOnce(&Self::Item), 

Do something with the item of a future, passing it on.

fn catch_unwind(self) -> CatchUnwind<Self> where
    Self: UnwindSafe, 

Catches unwinding panics while polling the future.

fn shared(self) -> Shared<Self>

Create a cloneable handle to this future where all handles will resolve to the same result.