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Packs ECMAScript/CommonJs/AMD modules for the browser. Allows you to split your codebase into multiple bundles, which can be loaded on demand. Supports loaders to preprocess files, i.e. json, jsx, es7, css, less, ... and your custom stuff.

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/*
	MIT License http://www.opensource.org/licenses/mit-license.php
	Author Tobias Koppers @sokra
*/

"use strict";

/**
 * Compare two arrays or strings by performing strict equality check for each value.
 * @template T [T=any]
 * @param {ArrayLike} a Array of values to be compared
 * @param {ArrayLike} b Array of values to be compared
 * @returns {boolean} returns true if all the elements of passed arrays are strictly equal.
 */

exports.equals = (a, b) => {
	if (a.length !== b.length) return false;
	for (let i = 0; i < a.length; i++) {
		if (a[i] !== b[i]) return false;
	}
	return true;
};

/**
 * Partition an array by calling a predicate function on each value.
 * @template T [T=any]
 * @param {Array} arr Array of values to be partitioned
 * @param {(value: T) => boolean} fn Partition function which partitions based on truthiness of result.
 * @returns {[Array, Array]} returns the values of `arr` partitioned into two new arrays based on fn predicate.
 */
exports.groupBy = (arr = [], fn) => {
	return arr.reduce(
		/**
		 * @param {[Array, Array]} groups An accumulator storing already partitioned values returned from previous call.
		 * @param {T} value The value of the current element
		 * @returns {[Array, Array]} returns an array of partitioned groups accumulator resulting from calling a predicate on the current value.
		 */
		(groups, value) => {
			groups[fn(value) ? 0 : 1].push(value);
			return groups;
		},
		[[], []]
	);
};