Struct futures_task::FutureObj

pub struct FutureObj<'a, T>(_);

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.

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

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

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

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