Struct jsonrpc_pubsub::oneshot::Sender

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

Expand description

A sender part of the channel.

Implementations

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impl<T> Sender<T>

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

Consume the sender and queue up an item to send.

This method returns right away and never blocks, there is no guarantee though that the message is received by the other end.

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pub fn send_and_wait(self, t: T) -> impl Future<Item = (), Error = ()>

Consume the sender and send an item.

The returned future will resolve when the message is received on the other end. Note that polling the future is actually not required to send the message as that happens synchronously. The future resolves to error in case the receiving end was dropped before being able to process the message.

Methods from Deref<Target = Sender<T>>

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pub fn poll_cancel(&mut self) -> Result<Async<()>, ()>

Polls this Sender half to detect whether the Receiver this has paired with has gone away.

This function can be used to learn about when the Receiver (consumer) half has gone away and nothing will be able to receive a message sent from send.

If Ready is returned then it means that the Receiver has disappeared and the result this Sender would otherwise produce should no longer be produced.

If NotReady is returned then the Receiver is still alive and may be able to receive a message if sent. The current task, however, is scheduled to receive a notification if the corresponding Receiver goes away.

Panics

Like Future::poll, this function will panic if it’s not called from within the context of a task. In other words, this should only ever be called from inside another future.

If Ok(Ready) is returned then the associated Receiver has been dropped, which means any work required for sending should be canceled.

If you’re calling this function from a context that does not have a task, then you can use the is_canceled API instead.

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pub fn is_canceled(&self) -> bool

Tests to see whether this Sender’s corresponding Receiver has gone away.

This function can be used to learn about when the Receiver (consumer) half has gone away and nothing will be able to receive a message sent from send.

Note that this function is intended to not be used in the context of a future. If you’re implementing a future you probably want to call the poll_cancel function which will block the current task if the cancellation hasn’t happened yet. This can be useful when working on a non-futures related thread, though, which would otherwise panic if poll_cancel were called.