Some comments after watching "Swift concurrency: Update a sample app".

await updateUI()

is *not* equivalent to

DispatchQueue.main.async { updateUI() }

"await" means continueWork() will only execute after updateUI() is done.
The presenter says a function with a defaulted empty completion handler is equivalent to an async function with discardable result. Not really.

await updateUI()

is *not* equivalent to

updateUI(completionHandler: { })

Same reason.
I'm also quite confused with the presenter removing the background dispatch queue and not explaining how save() and load() are now executing in the background. The actual data load and save operations are no async themselves so is the code really executing on a background thread?
It was my understanding that actors do not provide concurrency themselves and might even execute synchronously if they are not busy. In which case this new code would really not work as expected. Though I'm waiting for the behind the scenes session to find out more about this.

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More from @tclementdev

1 Jun
So... Swift actors are coming next week and I feel obligated to remind everyone that they're probably not the right tool for the job.

Thread 👇
Actors have had some success in the cloud/server space which makes sense there because actors are distributed and messaged asynchronously across the network. This however does not seem particularly relevant to mobile/desktop apps where there are very good reasons to not go async.
Async programming is hell. Because it causes pieces of code to be executed at some later time, every await needs to be carefully considered in ways that just weren't needed before. Executions might happen during the awaits and cause all sorts of unexpected situations.
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