flatMapIndexedTo
inline fun <E, R, D : KoneMutableList<in R>> KoneIterable<E>.flatMapIndexedTo(destination: D, transform: (index: UInt, E) -> KoneIterable<R>): D(source)
inline fun <E, R, D : KoneMutableSet<in R>> KoneIterable<E>.flatMapIndexedTo(destination: D, transform: (index: UInt, E) -> KoneIterable<R>): D(source)