Struct futures_util::future::Shared

source · [−]

pub struct Shared<Fut: Future> { /* private fields */ }

Expand description

Future for the shared method.

Implementations

impl<Fut> Shared<Fut> where
Fut: Future,
Fut::Output: Clone,

pub fn peek(&self) -> Option<&Fut::Output>

Returns Some containing a reference to this Shared’s output if it has already been computed by a clone or None if it hasn’t been computed yet or this Shared already returned its output from poll.

pub fn downgrade(&self) -> Option<WeakShared<Fut>>

Creates a new WeakShared for this Shared.

Returns None if it has already been polled to completion.

pub fn strong_count(&self) -> Option<usize>

Gets the number of strong pointers to this allocation.

Returns None if it has already been polled to completion.

Safety

This method by itself is safe, but using it correctly requires extra care. Another thread can change the strong count at any time, including potentially between calling this method and acting on the result.

pub fn weak_count(&self) -> Option<usize>

Gets the number of weak pointers to this allocation.

Returns None if it has already been polled to completion.

Safety

This method by itself is safe, but using it correctly requires extra care. Another thread can change the weak count at any time, including potentially between calling this method and acting on the result.

Trait Implementations

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

fn clone(&self) -> Self

Returns a copy of the value. Read more

1.0.0 · source

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

Performs copy-assignment from source. Read more

impl<Fut: Future> Debug for Shared<Fut>

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

Formats the value using the given formatter. Read more

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

fn drop(&mut self)

Executes the destructor for this type. Read more

impl<Fut> FusedFuture for Shared<Fut> where
Fut: Future,
Fut::Output: Clone,

fn is_terminated(&self) -> bool

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

impl<Fut> Future for Shared<Fut> where
Fut: Future,
Fut::Output: Clone,

type Output = <Fut as Future>::Output

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. Read more

impl<Fut: Future> Unpin for Shared<Fut>

Auto Trait Implementations

impl<Fut> !RefUnwindSafe for Shared<Fut>

impl<Fut> Send for Shared<Fut> where
Fut: Send,
<Fut as Future>::Output: Send + Sync,

impl<Fut> Sync for Shared<Fut> where
Fut: Send,
<Fut as Future>::Output: Send + Sync,

impl<Fut> !UnwindSafe for Shared<Fut>

Blanket Implementations

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

fn type_id(&self) -> TypeId

Gets the TypeId of self. Read more

impl<T> Borrow<T> for T where
T: ?Sized,

const: unstable · source

fn borrow(&self) -> &T

Immutably borrows from an owned value. Read more

impl<T> BorrowMut<T> for T where
T: ?Sized,

const: unstable · source

fn borrow_mut(&mut self) -> &mut T

Mutably borrows from an owned value. Read more

impl<T> From<T> for T

const: unstable · source

fn from(t: T) -> T

Returns the argument unchanged.

impl<T, U> Into<U> for T where
U: From<T>,

const: unstable · source

fn into(self) -> U

Calls U::from(self).

That is, this conversion is whatever the implementation of From<T> for U chooses to do.

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

type Output = <F as Future>::Output

The output that the future will produce on completion.

type IntoFuture = F

Which kind of future are we turning this into?

fn into_future(self) -> <F as IntoFuture>::IntoFuture

Creates a future from a value. Read more

impl<T> ToOwned for T where
T: Clone,

type Owned = T

The resulting type after obtaining ownership.

fn to_owned(&self) -> T

Creates owned data from borrowed data, usually by cloning. Read more

fn clone_into(&self, target: &mut T)

Uses borrowed data to replace owned data, usually by cloning. Read more

impl<T, U> TryFrom<U> for T where
U: Into<T>,

type Error = Infallible

The type returned in the event of a conversion error.

const: unstable · source

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

Performs the conversion.

impl<F, T, E> TryFuture for F where
F: Future<Output = Result<T, E>> + ?Sized,

type Ok = T

The type of successful values yielded by this future

type Error = E

The type of failures yielded by this future

fn try_poll(
self: Pin<&mut F>,
cx: &mut Context<'_>
) -> Poll<<F as Future>::Output>

Poll this TryFuture as if it were a Future. Read more

impl<T, U> TryInto<U> for T where
U: TryFrom<T>,

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

The type returned in the event of a conversion error.

const: unstable · source

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

Performs the conversion.