inline fun <T : Any> ContentResolver.itemsFor(
    crossinline queryRawData: ContentResolver.() -> Cursor,
    crossinline mapRawData: (Cursor) -> T): Flowable<T> =
    Flowable.generate<T, Cursor>(
        Callable<Cursor> { queryRawData(this) },
        BiFunction<Cursor, Emitter<T>, Cursor> { cursor, emitter ->
            if (cursor.moveToNext()) {
                emitter.onNext(mapRawData(cursor))
            } else {
                emitter.onComplete()
            }
            return@BiFunction cursor
        },
        Consumer<Cursor> { cursor -> cursor.close() }
    )