Struct futures_task::FutureObj

pub struct FutureObj<'a, T>(/* private fields */);

Expand description

A custom trait object for polling futures, roughly akin to Box<dyn Future<Output = T> + Send + 'a>.

This custom trait object was introduced as currently it is not possible to take dyn Trait by value and Box<dyn Trait> is not available in no_std contexts.

You should generally not need to use this type outside of no_std or when implementing Spawn, consider using BoxFuture instead.

Implementations§

impl<'a, T> FutureObj<'a, T>

pub fn new<F: UnsafeFutureObj<'a, T> + Send>(f: F) -> Self

Create a FutureObj from a custom trait object representation.

Trait Implementations§

impl<T> Debug for FutureObj<'_, T>

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

Formats the value using the given formatter. Read more

impl<'a, F: Future<Output = ()> + Send + 'a> From<Box<F>> for FutureObj<'a, ()>

fn from(boxed: Box<F>) -> Self

Converts to this type from the input type.

impl<'a> From<Box<dyn Future<Output = ()> + Send + 'a>> for FutureObj<'a, ()>

fn from(boxed: Box<dyn Future<Output = ()> + Send + 'a>) -> Self

Converts to this type from the input type.

impl<'a, T> From<FutureObj<'a, T>> for LocalFutureObj<'a, T>

fn from(f: FutureObj<'a, T>) -> Self

Converts to this type from the input type.

impl<'a, F: Future<Output = ()> + Send + 'a> From<Pin<Box<F>>> for FutureObj<'a, ()>

fn from(boxed: Pin<Box<F>>) -> Self

Converts to this type from the input type.

impl<'a> From<Pin<Box<dyn Future<Output = ()> + Send + 'a>>> for FutureObj<'a, ()>

fn from(boxed: Pin<Box<dyn Future<Output = ()> + Send + 'a>>) -> Self

Converts to this type from the input type.

impl<T> Future for FutureObj<'_, T>

type Output = T

The type of value produced on completion.

fn poll(self: Pin<&mut Self>, cx: &mut Context<'_>) -> Poll<T>

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

impl<T> Send for FutureObj<'_, T>

impl<T> Unpin for FutureObj<'_, T>

Auto Trait Implementations§

impl<'a, T> Freeze for FutureObj<'a, T>

impl<'a, T> !RefUnwindSafe for FutureObj<'a, T>

impl<'a, T> !Sync for FutureObj<'a, T>

impl<'a, T> !UnwindSafe for FutureObj<'a, T>

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,

fn borrow(&self) -> &T

Immutably borrows from an owned value. Read more

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

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

Mutably borrows from an owned value. Read more

impl<T> From<T> for T

fn from(t: T) -> T

Returns the argument unchanged.

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

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

type Error = Infallible

The type returned in the event of a conversion error.

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

Performs the conversion.

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.

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

Performs the conversion.

Layout§

Note: Most layout information is completely unstable and may even differ between compilations. The only exception is types with certain repr(...) attributes. Please see the Rust Reference's “Type Layout” chapter for details on type layout guarantees.

Size: 24 bytes