RawWaker in core::task - Rust
Description: A `RawWaker` allows the implementor of a task executor to create a `Waker` or a `LocalWaker` which provides customized wakeup behavior.

## RawWaker

# Struct RawWaker

1.36.0 · Source

    pub struct RawWaker { /* private fields */ }

Expand description

A `RawWaker` allows the implementor of a task executor to create a `Waker` or a `LocalWaker` which provides customized wakeup behavior.

It consists of a data pointer and a virtual function pointer table (vtable) that customizes the behavior of the `RawWaker`.

`RawWaker`s are unsafe to use. Implementing the `Wake` trait is a safe alternative that requires memory allocation.

## Implementations§

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### impl RawWaker

1.36.0 (const: 1.36.0) · Source

#### pub const fn new(data: *const (), vtable: &'static RawWakerVTable) -> RawWaker

Creates a new `RawWaker` from the provided `data` pointer and `vtable`.

The `data` pointer can be used to store arbitrary data as required by the executor. This could be e.g. a type-erased pointer to an `Arc` that is associated with the task. The value of this pointer will get passed to all functions that are part of the `vtable` as the first parameter.

It is important to consider that the `data` pointer must point to a thread safe type such as an `Arc<T: Send + Sync>` when used to construct a `Waker`. This restriction is lifted when constructing a `LocalWaker`, which allows using types that do not implement `Send + Sync` like `Rc<T>`.

The `vtable` customizes the behavior of a `Waker` which gets created from a `RawWaker`. For each operation on the `Waker`, the associated function in the `vtable` of the underlying `RawWaker` will be called.

## Trait Implementations§

1.36.0 · Source§

### impl Debug for RawWaker

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

Formats the value using the given formatter. Read more
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### impl PartialEq for RawWaker

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#### fn eq(&self, other: &RawWaker) -> bool

Tests for `self` and `other` values to be equal, and is used by `==`.
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#### fn ne(&self, other: &Rhs) -> bool

Tests for `!=`. The default implementation is almost always sufficient, and should not be overridden without very good reason.
1.36.0 · Source§

### impl StructuralPartialEq for RawWaker

## Auto Trait Implementations§

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### impl Freeze for RawWaker

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### impl RefUnwindSafe for RawWaker

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### impl !Send for RawWaker

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### impl !Sync for RawWaker

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### impl Unpin for RawWaker

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### impl UnwindSafe for RawWaker

## Blanket Implementations§

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### impl<T> Any for T
where T: 'static + ?Sized,

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#### fn type_id(&self) -> TypeId

Gets the `TypeId` of `self`. Read more
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### impl<T> Borrow<T> for T
where T: ?Sized,

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#### fn borrow(&self) -> &T

Immutably borrows from an owned value. Read more
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### impl<T> BorrowMut<T> for T
where T: ?Sized,

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

Mutably borrows from an owned value. Read more
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### impl<T> From<T> for T

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#### fn from(t: T) -> T

Returns the argument unchanged.

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

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#### fn into(self) -> U

Calls `U::from(self)`.

That is, this conversion is whatever the implementation of `From<T> for U` chooses to do.

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

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#### type Error = Infallible

The type returned in the event of a conversion error.
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#### fn try_from(value: U) -> Result<T, <T as TryFrom<U>>::Error>

Performs the conversion.
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### impl<T, U> TryInto<U> for T
where U: TryFrom<T>,

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#### type Error = <U as TryFrom<T>>::Error

The type returned in the event of a conversion error.
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#### fn try_into(self) -> Result<U, <U as TryFrom<T>>::Error>

Performs the conversion.