Actors 101

Using Swift
52

Here is something enlightening to read. Thank you, @aetherealtech, for writing this Concurrency 101 material.

A system of concurrency guaranteeing order is a contradiction. Concurrent means in parallel, which implies no guarantee of order. Guaranteeing order just reintroduces seriality. What are people asking for when they ask for a concurrency system to makes order guarantees?

The answer usually seems to be something about the order tasks are "started", in contrast to full serialization which implies one task is started and finished before the second task is started. First of all, this isn't something new to Swift concurrency. In this code:

  Thread.detach { print("Hello 1") }
  Thread.detach { print("Hello 2") }

The order of the print statements is indeterminate. That's the whole point of spawning new threads. There's no guarantee that the first thread "starts" before the second thread "starts".
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