export const groupBy: {
<A,K extends string>(f: (a: A) => K): (self: Iterable<A>) => Record<K, NonEmptyArray<A>>
<A,K extends string>(self: Iterable<A>, f: (a: A) => K): Record<K, NonEmptyArray<A>>
}
export const groupBy: {
<A,K extends string>(f: (a: A) => K): (self: Iterable<A>) => Record<K, NonEmptyArray<A>>
<A,K extends string>(self: Iterable<A>, f: (a: A) => K): Record<K, NonEmptyArray<A>>
}