toArray (for Iterators)

Creates a function that collects the elements of an iterator into an array. Use it with pipe.

const result = pipe(source, toArray());

::: info

In ordinary code, prefer the native Iterator.prototype.toArray: source.toArray(). Use this es-toolkit/fp/iterator variant when composing transformations with pipe.

:::

Usage

toArray()

toArray is the most common terminal step of an iterator pipeline: it pulls every element and returns them as an array. Because it consumes the whole iterator, it must not be used on an infinite iterator — bound the pipeline with take or takeWhile first. It delegates to the native Iterator.prototype.toArray.

import { pipe } from 'es-toolkit/fp';
import { map, toArray } from 'es-toolkit/fp/iterator';

// Materialize the transformed elements.
pipe(
  [1, 2, 3].values(),
  map(x => x * 2),
  toArray()
);
// Returns: [2, 4, 6]

Returns

((source: Iterator<T>) => T[]): A function that consumes an iterator and returns its elements as an array.