Struct BroadcastChannel

pub struct BroadcastChannel<T> { /* private fields */ }

A channel that broadcasts values received to one or more callbacks.

This type represents both a sender and a receiver in terms of determining whether a channel is “connected”. This is because at any time additional callbacks can be associated through this type while also allowing values to be sent to already-installed callbacks.

Because of this ability to attach future callbacks, a broadcast channel can be created with no associated callbacks. When a value is sent to a channel that has a BroadcastChannel connected to it, the value will be queued even if no callbacks are currently associated. To prevent this, use create_broadcaster()/into_broadcaster() to create a Broadcaster for this channel and drop all BroadcastChannel instances after callbacks have been associated.

Implementations

impl<T> BroadcastChannel<T>

where T: Unpin + Clone + Send + 'static,

pub fn unbounded() -> Self

Returns broadcast channel with no limit to the number of values enqueued.

pub fn bounded(capacity: usize) -> Self

Returns broadcast channel that limits queued values to capacity items.

pub fn build() -> Builder<T, Broadcast<T>>

Returns a builder for a broadcast channel.

pub fn send(&self, value: T) -> Result<(), T>

Sends value to this channel.

If the channel is full, this function will block the current thread until space is made available. If one channel’s on_receive is sending a value to a bounded channel, that on_receive should be on_receive_async instead and use send_async().

Errors

Returns Err(value) if the channel is disconnected.

pub fn send_async(&self, value: T) -> BroadcastAsync<'_, T>

Sends value to this channel asynchronously.

If the channel is full, this future will wait until space is made available before sending.

Errors

The returned future will return Err(value) if the channel is disconnected.

pub fn try_send(&self, value: T) -> Result<(), TrySendError<T>>

Tries to send value to this channel. Returns an error if unable to send.

Errors

• When the channel is disconnected, TrySendError::Disconnected will be returned.
• When the channel is full, TrySendError::Full will be returned.

pub fn force_send(&self, value: T) -> Result<Option<T>, T>

Sends value to this channel, removing the oldest unread value if the channel is full.

If the channel is full, the unread value will be returned in Ok(Some(unread_value)). If the channel has capacity, Ok(None) will be returned.

Errors

Returns value if the channel is disconnected.

pub fn create_receiver(&self) -> Receiver<T>

Creates a new receiver for this channel.

All receivers and callbacks must receive each value before the next value is able to be received.

pub fn on_receive<Map>(&self, on_receive: Map) -> CallbackHandle

where Map: FnMut(T) + Send + 'static,

Invokes on_receive each time a value is sent to this channel.

This function assumes on_receive may block while waiting on another thread, another process, another callback, a network request, a locking primitive, or any other number of ways that could impact other callbacks from executing.

pub fn on_receive_try<Map>(&self, on_receive: Map) -> CallbackHandle

where Map: FnMut(T) -> Result<(), CallbackDisconnected> + Send + 'static,

Invokes on_receive each time a value is sent to this channel. Once an error is returned, this callback will be removed from the channel.

This function assumes on_receive may block while waiting on another thread, another process, another callback, a network request, a locking primitive, or any other number of ways that could impact other callbacks from executing.

Once the last callback associated with a channel is removed, Senders will begin returning disconnected errors.

pub fn on_receive_nonblocking<Map>(&self, on_receive: Map) -> CallbackHandle

where Map: FnMut(T) + Send + 'static,

Invokes on_receive each time a value is sent to this channel.

This function assumes on_receive will not block while waiting on another thread, another process, another callback, a network request, a locking primitive, or any other number of ways that could impact other callbacks from executing in a shared environment.

pub fn on_receive_nonblocking_try<Map>(&self, on_receive: Map) -> CallbackHandle

where Map: FnMut(T) -> Result<(), CallbackDisconnected> + Send + 'static,

Invokes on_receive each time a value is sent to this channel. Once an error is returned, this callback will be removed from the channel.

This function assumes on_receive will not block while waiting on another thread, another process, another callback, a network request, a locking primitive, or any other number of ways that could impact other callbacks from executing in a shared environment.

Once the last callback associated with a channel is removed, Senders will begin returning disconnected errors.

pub fn on_receive_async<Map, Fut>(&self, on_receive: Map) -> CallbackHandle

where Map: FnMut(T) -> Fut + Send + 'static, Fut: Future<Output = ()> + Send + 'static,

Invokes on_receive each time a value is sent to this channel.

pub fn on_receive_async_try<Map, Fut>(&self, on_receive: Map) -> CallbackHandle

where Map: FnMut(T) -> Fut + Send + 'static, Fut: Future<Output = Result<(), CallbackDisconnected>> + Send + 'static,

Invokes on_receive each time a value is sent to this channel. The returned future will then be awaited. Once an error is returned, this callback will be removed from the channel.

Once the last callback associated with a channel is removed, Senders will begin returning disconnected errors.

impl<T> BroadcastChannel<T>

pub fn create_broadcaster(&self) -> Broadcaster<T>

Returns a Broadcaster that sends to this channel.

pub fn into_broadcaster(self) -> Broadcaster<T>

Returns this instance as a Broadcaster that sends to this channel.

Trait Implementations

impl<T> Clone for BroadcastChannel<T>

fn clone(&self) -> Self

Returns a copy of the value.

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

Performs copy-assignment from source.

impl<T> Default for BroadcastChannel<T>

where T: Unpin + Clone + Send + 'static,

fn default() -> Self

Returns an unbounded broadcast channel.

impl<T> Drop for BroadcastChannel<T>

fn drop(&mut self)

Executes the destructor for this type.

impl<T> From<BroadcastChannel<T>> for Notify<T>

fn from(value: BroadcastChannel<T>) -> Self

Converts to this type from the input type.

impl<T> From<BroadcastChannel<T>> for SharedNotify<T>

fn from(value: BroadcastChannel<T>) -> Self

Converts to this type from the input type.

impl<T, U> Unwrapped<U> for &BroadcastChannel<T>

where T: IntoOption<U> + Clone + Unpin + Send + 'static, U: Send + 'static,

type Value<'a> = U

The value type provided to the for each functions.

fn unwrapped_or_else(self, initial: impl FnOnce() -> U) -> Dynamic<U>

Returns a dynamic that is updated with the unwrapped contents of thie source.

fn for_each_unwrapped_try<ForEach>(self, for_each: ForEach) -> CallbackHandle

where ForEach: for<'a> FnMut(Self::Value<'a>) -> Result<(), CallbackDisconnected> + Send + 'static,

Invokes for_each when self is updated with a value that can be unwrapped.

fn unwrapped(self) -> Dynamic<T>

where T: Default,

Returns a dynamic that is updated with the unwrapped contents of thie source.

fn for_each_unwrapped<ForEach>(self, for_each: ForEach) -> CallbackHandle

where ForEach: for<'a> FnMut(Self::Value<'a>) + Send + 'static,

Invokes for_each when self is updated with a value that can be unwrapped.