PairTriplePairTripleCompletable.concat(this)concatMap { it }.Flowable.concat(this)Maybe.concat(this)concatMap { it }.Single.concat(this)flatMap { it }.flatMap { it }.flatMapSingle { it }.flatMap { it }.flatMapMaybe { it }.flatMap { it }.flatMapSingle { it }.flatMap { it }.Flowable emitted through an Flowable> . Same as calling switchMap { it }.Observable emitted through an Observable> . Same as calling switchMap { it }.Pair emission into a MapPair emission into a MapPair emission into a multimapPair emission into a multimapPairPairTriplePairTriplePairPair