Old @use_async still running

[fonsp]

I had a weird time debugging something today, until I found out that an old @use_async was still running. In this case I just commented out the entire callback, but the old callback was still running async.

Schermopname.2022-03-14.om.15.11.54.mov

[fonsp]

The infinite loop is caused by a second cell that does something like:

let
	dir_changed_time

	write(joinpath(dir, "_cache", "hello.txt"), "world")
end

Which I was trying to avoid by filtering inside my filewatching callback

[fonsp]

Maybe the set_value function from @use_state could also be invalidated when I shift+run the cell? I think the broken is that throwing the InterruptException was not working, and the old file watcher is still running. If that old set_state function would error("Invalidated"), then that might solve it

[Pangoraw]

Maybe the set_value function from @use_state could also be invalidated when I shift+run the cell

That's a great idea! if it throws an error after invalidation that's another way to kill the task.

[fonsp]

Something like this also does not work:

@use_task([output_dir]) do
	run(`$(Deno_jll.deno()) run --allow-read --allow-net https://deno.land/[email protected]/http/file_server.ts`)
end

When you re-run the cell, the old server is still running while the new one is starting up, which gives error: Uncaught (in promise) AddrInUse: Address already in use (os error 48).

I think we should await shutting down the last task before starting the next one?