reduceLazy() function

reduce와 동일하게 작동하는 고차 함수 버전입니다.

Signature:

declare function reduceLazy<
  T extends Iterable<unknown> | AsyncIterable<unknown>,
  Acc,
>(
  f: SyncReducer<Acc, IterableInfer<T>> | AsyncReducer<Acc, IterableInfer<T>>,
  seed: Acc,
): (iterable: InferCarrier<T>) => ReturnValueType<T, Acc>;

Example

Type must be provided for stand alone call.

const reduce = reduceLazy((a: number, b: number) => a + b, 5);

reduce([1, 2, 3]); // number
reduce(toAsync([1, 2, 3])); // Promise<number>

Fit perfectly with pipe

pipe(
  [1, 2, 3, 4],
  reduceLazy((a, b) => a + b, 5),
); // 15

You can use asynchronous callback

await pipe(
  [1, 2, 3, 4],
  reduceLazy(async (a, b) => a + b, 5),
); // 15

AsyncIterable doesn't matter.

await pipe(
  [1, 2, 3, 4],
  toAsync,
  reduceLazy((a, b) => a + b, 5),
); // 15

Open Source Code