/**
 * A sink that collects first `n` distinct inputs into a set.
 *
 * @tsplus static effect/core/stream/Sink.Ops collectAllToSetN
 */
export function collectAllToSetN<In>(
  n: number
): Sink<never, never, In, In, HashSet<In>> {
  return Sink.foldWeighted(
    HashSet.empty<In>(),
    (set, a) => (set.has(a) ? 0 : 1),
    n,
    (set, a) => set.add(a)
  )
}