modulePattern.md

Module pattern

The module pattern allows to declare both public and private methods and variables inside a single object, shielding particular parts of an object.

Example:

var counting = (function(){
  var counter = 0;

  return {
    incrementCounter: function(){
      return counter++;
    },

    decreaseCounter: function(){
      return counter--;
    }
  }
})();

counting.incrementCounter();

counter.decreaseCounter();

In the example above, other parts of the code are not able to read the value returned from incrementCounter and decreaseCounter.

Advantages

Supports private data. Public parts of our code are able to touch private parts, however, the outside world is unable to touch the class' private parts.

Disadvantages

• We can't access private parts in methods that are added to the object later on.

• Automated unit tests for private members is not possible.