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                let orig = {
	a: new Date(),
	b: NaN,
	c: new Function(),
	d: undefined,
	e: function() {},
	f: Number,
	g: false,
	h: Infinity,
	i: ['1', '2', '3'],
	j: {
		a: 1,
		b: 2,
		c: 3

let copy = function (obj) {

	// Methods

	 * Create an immutable copy of an object
	 * @return {Object}
	let cloneObj = function () {

		// Create new object
		let clone = {};

		// Loop through each item in the original
		// Recursively copy it's value and add to the clone
		for (let key in obj) {
			if (obj.hasOwnProperty(key)) {
				clone[key] = copy(obj[key]);

		return clone;


	 * Create an immutable copy of an array
	 * @return {Array}
	let cloneArr = function () {
		return (item) {
			return copy(item);

	// Inits

	// Get object type
	let type =, -1).toLowerCase();

	// If an object
	if (type === 'object') {
		return cloneObj();

	// If an array
	if (type === 'array') {
		return cloneArr();

	// Otherwise, return it as-is
	return obj;


// Create an immutable copy of the original object
let newObj = copy(orig);

// Update copy
newObj.i[0] = 'a';
newObj.j.a = 'a';