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 * Check if two objects or arrays are equal
 * (c) 2021 Chris Ferdinandi, MIT License,
 * @param  {*}       obj1 The first item
 * @param  {*}       obj2 The second item
 * @return {Boolean}       Returns true if they're equal in value
function isEqual (obj1, obj2) {

	 * More accurately check the type of a JavaScript object
	 * @param  {Object} obj The object
	 * @return {String}     The object type
	function getType (obj) {
		return, -1).toLowerCase();

	function areArraysEqual () {

		// Check length
		if (obj1.length !== obj2.length) return false;

		// Check each item in the array
		for (let i = 0; i < obj1.length; i++) {
			if (!isEqual(obj1[i], obj2[i])) return false;

		// If no errors, return true
		return true;


	function areObjectsEqual () {

		if (Object.keys(obj1).length !== Object.keys(obj2).length) return false;

		// Check each item in the object
		for (let key in obj1) {
						if (, key)) {
				if (!isEqual(obj1[key], obj2[key])) return false;

		// If no errors, return true
		return true;


	function areFunctionsEqual () {
		return obj1.toString() === obj2.toString();

	function arePrimativesEqual () {
		return obj1 === obj2;

	// Get the object type
	let type = getType(obj1);

	// If the two items are not the same type, return false
	if (type !== getType(obj2)) return false;

	// Compare based on type
	if (type === 'array') return areArraysEqual();
	if (type === 'object') return areObjectsEqual();
	if (type === 'function') return areFunctionsEqual();
	return arePrimativesEqual();


let arr1 = [1, 2, 3, 4, 5];
let arr2 = [1, 2, 3, 4, 5];
console.log(isEqual(arr1, arr2));

let arrObj1 = [1, 2, {
	a: 1,
	b: 2,
	c: 3
}, 4, 5];
let arrObj2 = [1, 2, {
	c: 3,
	b: 2,
	a: 1
}, 4, 5];
console.log(isEqual(arrObj1, arrObj2));

let arr3 = [5, 4, 3, 2, 1];
console.log(isEqual(arr1, arr3));