Module sync

Structs

• CancellationToken A token which can be used to signal a cancellation request to one or more tasks.
• DropGuard A wrapper for cancellation token which automatically cancels it on drop. It is created using drop_guard method on the CancellationToken.
• PollSemaphore A wrapper around Semaphore that provides a poll_acquire method.
• PollSendError Error returned by the PollSender when the channel is closed.
• PollSender A wrapper around mpsc::Sender that can be polled.
• ReusableBoxFuture A reusable Pin<Box<dyn Future<Output = T> + Send + 'a>>.
• WaitForCancellationFuture A Future that is resolved once the corresponding CancellationToken is cancelled.
• WaitForCancellationFutureOwned A Future that is resolved once the corresponding CancellationToken is cancelled.