es-toolkit/dist/fp/array/take.js

A state-of-the-art, high-performance JavaScript utility library with a small bundle size and strong type annotations.

const require_take = require("../../array/take.js");
const require_lazy = require("../_internal/lazy.js");
//#region src/fp/array/take.ts
/**
* Creates a function that returns the first `count` elements of an array. If
* `count` is greater than the array length, the whole array is returned. Use it
* with {@link pipe}.
*
* The returned function is **lazy-capable** for a non-negative integer `count`:
* inside a {@link pipe} it stops the walk as soon as `count` elements have been
* collected, so preceding lazy functions never process the rest of the input.
*
* @template T - The type of elements in the array.
* @param count - The number of elements to take from the front of the array.
* @returns A function that maps a `readonly T[]` to a new `T[]`.
*
* @example
* import { pipe, take } from 'es-toolkit/fp';
*
* pipe([1, 2, 3, 4, 5], take(3)); // => [1, 2, 3]
*
* @example
* // Early termination: `map` only runs three times.
* pipe([1, 2, 3, 4, 5], map(expensive), take(3));
*/
function take(count) {
	function takeEager(array) {
		return require_take.take(array, count);
	}
	if (!Number.isInteger(count) || count < 0) return takeEager;
	const takeLazy = require_lazy.createLazyFunction((value, index, emit) => {
		if (index >= count) return false;
		emit(value);
		return index < count - 1;
	});
	return require_lazy.combineEagerAndLazyFunctions(takeEager, takeLazy, { shortCircuit: true });
}
//#endregion
exports.take = take;