Struct ReusableBoxFuture

pub struct ReusableBoxFuture<'a, T> { /* private fields */ }

A reusable Pin<Box<dyn Future<Output = T> + Send + 'a>>.

This type lets you replace the future stored in the box without reallocating when the size and alignment permits this.

Implementations

impl<'a, T> ReusableBoxFuture<'a, T>

pub fn new<F>(future: F) -> Self

where F: Future<Output = T> + Send + 'a,

Create a new ReusableBoxFuture<T> containing the provided future.

pub fn set<F>(&mut self, future: F)

where F: Future<Output = T> + Send + 'a,

Replace the future currently stored in this box.

This reallocates if and only if the layout of the provided future is different from the layout of the currently stored future.

pub fn try_set<F>(&mut self, future: F) -> Result<(), F>

where F: Future<Output = T> + Send + 'a,

Replace the future currently stored in this box.

This function never reallocates, but returns an error if the provided future has a different size or alignment from the currently stored future.

pub fn get_pin(&mut self) -> Pin<&mut (dyn Future<Output = T> + Send)>

Get a pinned reference to the underlying future.

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

Poll the future stored inside this box.

Trait Implementations

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

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

Formats the value using the given formatter.

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

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

Poll the future stored inside this box.

type Output = T

The type of value produced on completion.

impl<T> Sync for ReusableBoxFuture<'_, T>

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: 16 bytes