Struct futures_util::task::WakerRef

pub struct WakerRef<'a> {
    waker: ManuallyDrop<Waker>,
    _marker: PhantomData<&'a ()>,
}

A Waker that is only valid for a given lifetime.

Note: this type implements Deref<Target = Waker>, so it can be used to get a &Waker.

Fields

waker: ManuallyDrop<Waker>

_marker: PhantomData<&'a ()>

Implementations

impl<'a> WakerRef<'a>

pub fn new(waker: &'a Waker) -> WakerRef<'a>

Create a new WakerRef from a Waker reference.

pub fn new_unowned(waker: ManuallyDrop<Waker>) -> WakerRef<'a>

Create a new WakerRef from a Waker that must not be dropped.

Note: this if for rare cases where the caller created a Waker in an unsafe way (that will be valid only for a lifetime to be determined by the caller), and the Waker doesn’t need to or must not be destroyed.

Methods from Deref<Target = Waker>

pub fn wake_by_ref(&self)

Wakes up the task associated with this Waker without consuming the Waker.

This is similar to wake(), but may be slightly less efficient in the case where an owned Waker is available. This method should be preferred to calling waker.clone().wake().

pub fn will_wake(&self, other: &Waker) -> bool

Returns true if this Waker and another Waker would awake the same task.

This function works on a best-effort basis, and may return false even when the Wakers would awaken the same task. However, if this function returns true, it is guaranteed that the Wakers will awaken the same task.

This function is primarily used for optimization purposes — for example, this type’s clone_from implementation uses it to avoid cloning the waker when they would wake the same task anyway.

pub fn as_raw(&self) -> &RawWaker

🔬This is a nightly-only experimental API. (waker_getters)

Gets a reference to the underlying RawWaker.

Trait Implementations

impl<'a> Debug for WakerRef<'a>

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

Formats the value using the given formatter.

impl Deref for WakerRef<'_>

type Target = Waker

The resulting type after dereferencing.

fn deref(&self) -> &Waker

Dereferences the value.