mapToList

fun <T, R> Flowable<List<T>>.mapToList(mapper: (T) -> R): Flowable<List<R>>

fun <T, R> Observable<List<T>>.mapToList(mapper: (T) -> R): Observable<List<R>>

fun <T : Any, R : Any> Single<List<T>>.mapToList(mapper: (T) -> R): Single<List<R>>