@ctietze there's an example in last years AsyncAlgorithms wwdc2022-110355 talk. The flow is AsyncStream (user input queries) of AsyncSequences (debounced queries) to AsyncChannel (results)
@glotcha AsyncChannel from the async-algorithms package sounds interesting. I have to read up on the reactice concepts more, though, to figure out if I need "back pressure" :)
@ctietze deciphering the docs here is very tricky. you say batches isn't that equivalent to "back-pressure"... meaning you want to ensure "that the production of values does not exceed the consumption of values from iteration" giving you an opportunity to process the multiple datasources for each search (iteration) before updating the UI state.
@ctietze An AsyncStream or some custom AsyncSequence is completely fine for this. Not sure why you’d think that’s only for long running tasks.
In my experience an AsyncSequence can be used for most things a publisher can be used for.
It’s not always easier though.
But it appears that when for-in stream consumption itself is in a Task, and that is being cancelled, the stream is terminated with cancellation as well.
Not sure if spawning 5 Tasks inside the stream to request data from all data sources, and then cancelling these tasks if the stream is cancelled is making this simpler to understand, though.
@ctietze Haven't really used it much, but yeah, some AsyncSequence or something else that you can await for item in doTheThing() { ... } would probably be the best, but I don’t remember the exact type one uses for that.
But don’t use an array of arrays if the batches are just because that's how e.g. a paged request sends you the data. Do a one-dimensional array and just hand them to the AsyncStream in batches.
OTOH if you want to send categories of items (like groups in a table view) as batches, then of course the array of arrays makes sense.
@ctietze Did I understand the problem right? You want to get list items as they arrive, not delay the notification until all have arrived, right? Otherwise, a colleague suggested withThrowingTaskGroup(of:), which is also a cool thing to have.
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