alive? vs finished? vs status

[j-manu]

finished? returns true after self and child tasks have completed execution

status can be :initialized, :running, :completed, :stopped or :failed

1. When is alive? false?
2. Completed execution means status is in :completed, :stopped or :failed right?

[ioquatix]

Generally speaking, the only interface you should depend on is wait. finished? relates to whether that part of the task tree has finished executing, including all children.

1. alive? is false if the fiber does not exist yet or has completed execution:

   async/lib/async/task.rb

   Lines 117 to 120 in ffd019d

   	# Whether the internal fiber is alive, i.e. it
   	def alive?
   	@fiber&.alive?
   	end

   note that @fiber starts out as nil.
2. Yes, that's correct. There is a diagram here that should help: https://socketry.github.io/async/guides/asynchronous-tasks/index#task-lifecycle

[j-manu]

Thanks.

Generally speaking, the only interface you should depend on is wait. finished? relates to whether that part of the task tree has finished executing, including all children.

Yeah but finished? is very useful when you have nested async tree and you don't want to wait on the task but periodically check whether the task and all its children have completed.

My use case: When a websocket connection is initiated, an async task with timeout is spawned. The task itself has multiple nested async tasks. The connection handler has a loop which loops until task.finished? . The tasks use a an instance of Thread::Queue which is read from in the loop and sent via the websocket connection

alive? is false if the fiber does not exist

When can this happen when using Async {} ?

Yes, that's correct. There is a diagram here that should help: https://socketry.github.io/async/guides/asynchronous-tasks/index#task-lifecycle

Yeah, I had seen that but wanted to confirm. Would you accept a PR to add completed_execution? to task? Right now,
if you want that, you have to do %i[status completed failed].include?(status)