playing with rxjava2

rx-test.kt

fun observable1() =
		Observable.fromCallable {
			print("new callable 1\n")
			true
		}

fun observable2() =
		Observable.fromCallable {
			print("new callable 2\n")
			true
		}

fun observable3() =
		Observable.interval(1, TimeUnit.SECONDS).map{1}

fun transformer() =
		ObservableTransformer<Int, Unit> {
			Observable.combineLatest(
					observable1(),
					observable2(),
					it,
					Function3 { t1, t2, t3 -> print("t1: $t1  t2: $t2  t3: $t3") }
			)
		}

fun main(args: Array<String>){
	observable3().compose(transformer()).subscribe()
	while (true) {}
}

The result

new callable 1
new callable 2
t1: true  t2: true  t3: 1
t1: true  t2: true  t3: 1
t1: true  t2: true  t3: 1
t1: true  t2: true  t3: 1
t1: true  t2: true  t3: 1
t1: true  t2: true  t3: 1
t1: true  t2: true  t3: 1
t1: true  t2: true  t3: 1
t1: true  t2: true  t3: 1
t1: true  t2: true  t3: 1
t1: true  t2: true  t3: 1