Need help with Swift concurrency and Obj C interoperability

[mattie]

Fantastic! Just make sure you understand the implications of this bridging and how non-isolated async functions behave. They are not identical to Obj-C completion handlers.

In fact, there is a proposal forming to address exactly this:

[Pitch] Inherit isolation by default for async functions

Hello, Swift evolution! SE-0338 specifies that nonisolated async functions never run on an actor's executor. This design decision was made to prevent unnecessary serialization and contention for the actor by switching off of the actor to run the nonisolated async function, and any new tasks it creates that inherit isolation. The actor is then free to make forward progress on other work. This behavior is especially important for preventing unexpected overhang on the main actor. However, based o…