Helper function to clone a given object instance

clone.js

/**
 * Helper function to clone a given object instance
 * @param  {Object} obj		Object that is going to be cloned
 * @return {Object}			Object cloned
 */
function clone (obj)
{
	// Handle the 3 simple types, and null or undefined
	if (null === obj || "object" != typeof obj) return obj;

	var copy;
	// Handle Date
	if (obj instanceof Date) {
		copy = new Date();
		copy.setTime(obj.getTime());
		return copy;
	}
	// Handle Array
	if (obj instanceof Array) {
		copy = [];
		for (var i = 0, len = obj.length; i < len; i++) {
			copy[i] = clone(obj[i]);
		}
		return copy;
	}
	// Handle Object
	if (obj instanceof Object) {
		copy = {};
		for (var attr in obj) {
			if (obj.hasOwnProperty(attr)) copy[attr] = clone(obj[attr]);
		}
		return copy;
	}

	throw new Error("Unable to copy obj! Its type isn't supported.");
}