<https://android.googlesource.com/platform/framewo...

# coroutines

[Paul Woitaschek]

https://android.googlesource.com/platform/frameworks/support/+/refs/heads/androidx-master-dev/lifecycle/lifecycle-viewmodel-ktx/src/main/java/androidx/lifecycle/ViewModel.kt
Why don't they cancel the scope directly but instead get a reference to the context and cancel that only?

[streetsofboston]

Not sure…. because CoroutineScope.cancel() does just that…. maybe someone didn’t realize this extension method existed 🙂

[Paul Woitaschek]

Just found out why:
https://android.googlesource.com/platform/frameworks/support/+/refs/heads/androidx-master-dev/lifecycle/lifecycle-viewmodel/src/main/java/androidx/lifecycle/ViewModel.java#183

[streetsofboston]

I’m not sure how closeWithRuntimeException explains this..

[Paul Woitaschek]

It's called by clear. They have a map where they put all sorts of stuff inside and if it's cancellable they cancel it. That's why they made a custom scope that implements cancellable.

[streetsofboston]

Ah… it’s not about calling this.cancel() vs coroutineContext.cancel(). Your question is about why calling it through a Closable interface…

[Paul Woitaschek]

I actually had 2 questions but only asked one 😄
So back to my original question: Is that completely equivalent? (cancelling the context vs cancelling the scope)

[streetsofboston]

Yup. It looks like it. Just do ‘go to definition’ in your IDE of both extension functions and see how they’re implemented; basically the same.