CoroutineDispatcher's names

CoroutineDispatcher’s names are too heterogeneous (CommonPool, Unconfined) and programmer isn’t helped to collate these in the same hierarchy. Other CoroutineDispatchers have too common name (Swing, JavaFX) and are subjects to name clash: Look And Feel engine can also expose “Swing” and “JavaFX” singletons.

My prosose is to define a common suffix like “CoroutineDispatcher”, “CDispatcher” or simply “Dispatcher” to grouping names.

I.E.

1. CommonDispatcher
2. UnconfinedDispatcher
3. SwingDispatcher
4. JavaFXDispatcher

launch(CommonDispatcher) {
    . . .
}

[voddan]

My issue with coroutine dispatchers not being organized in a hierarchy is poor discoverability. For example, if I want to use a coroutine builder, but forgot the spelling of a dispatcher I need, there is currently no better option than reading the documentation.

I propose to introduce a global singleton Dispatcher for serving as a hierarchy root. Then all coroutine dispatchers can be its extension properties val Dispatcher.Unconfined get() = ... and be used as Dispatcher.Unconfined.

The cost is that we have to use the prefix. The benefit is that IDE now lists all dispatchers for me.

[chrisbanes]

I like the flexibility of @LouisCAD’s suggestion. Being able to provide both Android.Main (async) and Android.UI (vsync) dispatchers, but I agree with @adamp in https://github.com/Kotlin/kotlinx.coroutines/issues/427#issuecomment-403562661 that having two dispatchers would be confusing too.

I still think Dispatchers.Main is an unfortunate name since it’s such a generic noun. Maybe Dispatchers.Android to be similar to JavaFx and Swing?