val flow: Flow<Int> = observableOf(1, 2, 3).asFlow()
val observable: Observable<Int> = flowOf(1, 2, 3).asObservable()

fun doSomething() {
    singleFromCoroutine { getSomething() }
        .subscribe { println(it) }
}

suspend fun getSomething(): String {
    delay(1.seconds)
    return "something"
}

val defaultScheduler = Dispatchers.Default.asScheduler()
val computationDispatcher = computationScheduler.asCoroutineDispatcher()

val scope =
    disposableScope {
        observable.subscribeScoped(...) // Subscription will be disposed when the scope is disposed

        doOnDispose {
            // Will be called when the scope is disposed
        }

        someDisposable.scope() // `someDisposable` will be disposed when the scope is disposed
    }

// At some point later
scope.dispose()

class MyPresenter(
    private val view: MyView,
    private val longRunningAction: Completable
) : DisposableScope by DisposableScope() {

    init {
        doOnDispose {
            // Will be called when the presenter is disposed
        }
    }

    fun load() {
        view.showProgressBar()

        // Subscription will be disposed when the presenter is disposed
        longRunningAction.subscribeScoped(onComplete = view::hideProgressBar)
    }
}

class MyActivity : AppCompatActivity(), DisposableScope by DisposableScope() {
    override fun onCreate(savedInstanceState: Bundle?) {
        super.onCreate(savedInstanceState)

        MyPresenter(...).scope()
    }

    override fun onDestroy() {
        dispose()

        super.onDestroy()
    }
}

object MyPlugin : ReaktivePlugin {
    override fun <T> onAssembleObservable(observable: Observable<T>): Observable<T> =
        object : Observable<T> {
            private val traceException = TraceException()

            override fun subscribe(observer: ObservableObserver<T>) {
                observable.subscribe(
                    object : ObservableObserver<T> by observer {
                        override fun onError(error: Throwable) {
                            observer.onError(error, traceException)
                        }
                    }
                )
            }
        }

    override fun <T> onAssembleSingle(single: Single<T>): Single<T> =
        TODO("Similar to onAssembleSingle")

    override fun <T> onAssembleMaybe(maybe: Maybe<T>): Maybe<T> = 
        TODO("Similar to onAssembleSingle")

    override fun onAssembleCompletable(completable: Completable): Completable =
        TODO("Similar to onAssembleSingle")

    private fun ErrorCallback.onError(error: Throwable, traceException: TraceException) {
        if (error.suppressedExceptions.lastOrNull() !is TraceException) {
            error.addSuppressed(traceException)
        }
        onError(error)
    }

    private class TraceException : Exception()
}