Hello, I was playing around with `coroutines` to u...

# getting-started

[Ahmed]

Hello, I was playing around with coroutines to understand them better on this playground. Although, the runBlocking works as I would expect it to work, with the structured concurrency and waiting for all of the coroutines to finish.

But within the same code if you uncomment the scope.launch and comment out the runBlocking , The main completes without letting the scope finish.
• Do the work in scope still completes? And if I want it to complete first, how would I do that, since I cannot call join on it.

[Joffrey]

Does the work in scope still completes?

No, the program terminates before everything is done, because you don't wait for it

And if I want it to complete first, how would I do that, since I cannot call join on it

If you want coroutines to complete, you have to wait for them. If you want your main() method to wait for them, it means you want to block the main thread, so runBlocking is appropriate. You could also choose to use suspend fun main() with or without a coroutineScope { ... } block.

[Ahmed]

I can see now that both IO and Default executes on DefaultDispatcher-worker-{NUM} .

Why does Unconfined says that it's working in kotlinx.coroutines.DefaultExecutor

A coroutine dispatcher that is not confined to any specific thread.

And I am not sure if I understand the event loop terminology fully.

Does it mean it can outlive it's scope to complete the work?

[Ruckus]

The next sentence in the documentation explains what that means:

It executes the initial continuation of a coroutine in the current call-frame and lets the coroutine resume in whatever thread that is used by the corresponding suspending function, without mandating any specific threading policy.