CrabDude

// Public
function Constructor(...) {
  this.membername = value;
}
Constructor.prototype.membername = value;

// Private
function Constructor(...) {
  var that = this;
  var membername = value;

CrabDude

/* Pvt.js - JavaScript Private Instance Members
 * By Adam Crabtree http://noderiety.com/
 * MIT Licensed.
 */

/**
* Generate a private member store
* @returns {function} The private member accessor function
*/
function Pvt() {

CrabDude

/* Privates.js - Simple JavaScript Inheritance With Inheritable Private Variables
 * By Adam Crabtree http://noderiety.com/
 * MIT Licensed.
 * 
 * Forked from:
 * Simple JavaScript Inheritance
 * By John Resig http://ejohn.org/
 * http://ejohn.org/blog/simple-javascript-inheritance/
 * Inspired by base2 and Prototype
 */

CrabDude

// Utilize a closure to keep the private members private
var Person = (function() {

  // Generate a private instance member accessor function "pvt"
  var pvt = Pvt(),

    // private static member
    species = "Homo sapien";
  
  var Self = function(isDancing) {

CrabDude

// Class.extend takes a function that returns the options object
//     it is passed the accessor function generated in the Pvt.js example above
var Person = Class.extend(function(pvt) {

  // private static member
  var species = "Homo sapien";
  
  return {
    init: function(isDancing) {
      // pvt(this).invisible === undefined

CrabDude

// NOT AN APPLICATION, I JUST WANTED TO TAKE YOUR TEST. =)

// 1: how could you rewrite the following to make it shorter?
if (foo) {
  bar.doSomething(el);
} else {
  bar.doSomethingElse(el);
}

// ANSWER