JS Module and Singleton

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JavaScript is a protypal language but has syntax that is more similar to a classical language which can be confusing.

Function as module (using self-executing function ) is a way to do functions better in some instances.
Function as module safeguards against values being exposed b/c it limits scope:
(function () {
  var ...
  function ...
  function ...
}());

This method only allows access to the values it wants you to have access to.

A Module Pattern

var singleton = (function () {
  var privateVariable;
  function privateFunction(x) {
    ...privateVariable...
  }
  return {
    firstMethod: function (a, b) {
      ...privateVariable...
    },
    secondMethod: function (c) {
      ...privateFunction() ...
    }
  };
}());

Recipe: Power Constructors
1. Make an object using any means available:
   Object literal
   new
   Object.create
   call another power constructor
2. Define some variables and function
   these will become private members of the object that is being constructed
3. Augment the object with privileged methods
   a privileged method is a method that is public but closes over the private state
4. Return the object

Step 1 - make an object:
function myPowerConstructor(x) {
  var that = otherMaker(x);
 }
Step 2 - create secret variables/functions
function myPowerConstructor(x) {
  var that = otherMaker(x);  // here another constructor(otherMaker()) is being asked to make var that
  var secret = f(x);
 }


Review: http://javascript.info/tutorial/all-one-constructor-pattern