§8. Concurrency and asynchronous chains

In this chapter

8.1 Execution model	The unit of execution is the task
8.2 Suspension points	A task can yield its thread only at suspension points
8.3 Task	Task<T, E> is a lazy computation.
8.4 Chains	A chain links asynchronous steps so that either the whole chain is executed or the first unhandled error is returned.
8.5 Structured concurrency	spawn is allowed only lexically inside scope { …
8.6 Cancellation and deadlines	Cancellation is cooperative
8.7 Channels and select	tx.send(x) suspends when the buffer is full; cap
8.8 Local actors	Messages are processed strictly one at a time, in the order of arrival from each sender.
8.9 Software transactional memory	atomic { … } executes the body as a serialisable transaction over TVars.