Struct futures_task::future_obj::LocalFutureObj

pub struct LocalFutureObj<'a, T> {
    future: *mut dyn Future<Output = T> + 'static,
    drop_fn: unsafe fn(_: *mut dyn Future<Output = T> + 'static),
    _marker: PhantomData<&'a ()>,
}

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

Fields

future: *mut dyn Future<Output = T> + 'static

drop_fn: unsafe fn(_: *mut dyn Future<Output = T> + 'static)

_marker: PhantomData<&'a ()>

Implementations

impl<'a, T> LocalFutureObj<'a, T>

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

Create a LocalFutureObj from a custom trait object representation.

pub unsafe fn into_future_obj(self) -> FutureObj<'a, T>

Converts the LocalFutureObj into a FutureObj.

Safety

To make this operation safe one has to ensure that the UnsafeFutureObj instance from which this LocalFutureObj was created actually implements Send.

Trait Implementations

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

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

Formats the value using the given formatter.

impl<T> Drop for LocalFutureObj<'_, T>

fn drop(&mut self)

Executes the destructor for this type.

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

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

Converts to this type from the input type.

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

fn from(boxed: Box<dyn Future<Output = ()> + '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 = ()> + 'a> From<Pin<Box<F>>> for LocalFutureObj<'a, ()>

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

Converts to this type from the input type.

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

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

Converts to this type from the input type.

impl<T> Future for LocalFutureObj<'_, 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> Unpin for LocalFutureObj<'_, T>