arrow-core/arrow.core/flatten

flatten

fun <A, B> Either<A, Either<A, B>>.flatten(): Either<A, B>
inline fun <A, B> Ior<A, Ior<A, B>>.flatten(combine: (A, A) -> A): Ior<A, B>
fun <A> Iterable<Iterable<A>>.flatten(): List<A>
fun <E> NonEmptyList<NonEmptyList<E>>.flatten(): NonEmptyList<E>
fun <A> Option<Option<A>>.flatten(): Option<A>
fun <A> Sequence<Sequence<A>>.flatten(): Sequence<A>