ObservableSample.kt

Observable.just(1)
        .flatMap { digit ->
            Observable.just("my digit is $digit")
        }
        .flatMap { string ->
            Observable.just("awesome $string")
        }
        .subscribeOn(io())
        .observeOn(mainThread())
        .subscribe { string ->
            Log.e("Monad", string)
        }