function mapNotNullish mapNotNullish<T,U,>(fn: (item: T) => U | null | undefined): unknown Curried map that drops null/undefined results in one pass. Curried adapter over @std/collections.mapNotNullish. Replaces the two-step pattern: compact(map(fn)(array)) Type Parameters T U Parameters fn: (item: T) => U | null | undefined Return Type unknown