Struct futures::executor::NotifyHandle

pub struct NotifyHandle { /* fields omitted */ }

A NotifyHandle is the core value through which notifications are routed in the futures crate.

All instances of Task will contain a NotifyHandle handle internally. This handle itself contains a trait object pointing to an instance of the Notify trait, allowing notifications to get routed through it.

The NotifyHandle type internally does not codify any particular memory management strategy. Internally it contains an instance of *mut UnsafeNotify, and more details about that trait can be found on its own documentation. Consequently, though, the one constructor of this type, NotifyHandle::new, is unsafe to call. It is not recommended to call this constructor directly.

If you're working with the standard library then it's recommended to work with the Arc type. If you have a struct, T, which implements the Notify trait, then you can construct this with NotifyHandle::from(t: Arc<T>). The coercion to UnsafeNotify will happen automatically and safely for you.

When working externally from the standard library it's recommended to provide a similar safe constructor for your custom type as opposed to recommending an invocation of NotifyHandle::new directly.

Implementations

impl NotifyHandle

pub unsafe fn new(inner: *mut dyn UnsafeNotify) -> NotifyHandle

Constructs a new NotifyHandle directly.

Note that most code will not need to call this. Implementers of the UnsafeNotify trait will typically provide a wrapper that calls this but you otherwise shouldn't call it directly.

If you're working with the standard library then it's recommended to use the NotifyHandle::from function instead which works with the safe Arc type and the safe Notify trait.

pub fn notify(&self, id: usize)

Invokes the underlying instance of Notify with the provided id.

Trait Implementations

impl Clone for NotifyHandle

fn clone(&self) -> Self

Returns a copy of the value.

fn clone_from(&mut self, source: &Self)

Performs copy-assignment from source.

impl Debug for NotifyHandle

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

Formats the value using the given formatter.

impl Drop for NotifyHandle

fn drop(&mut self)

Executes the destructor for this type.

impl<T: Notify> From<&'static T> for NotifyHandle

fn from(src: &'static T) -> NotifyHandle

Performs the conversion.

impl<T> From<Arc<T>> for NotifyHandle where
    T: Notify + 'static, 

fn from(rc: Arc<T>) -> NotifyHandle

Performs the conversion.

impl Send for NotifyHandle

impl Sync for NotifyHandle