Modular Programming with JavaScript

A look at a non-modular example

Let's consider an extremely simple example and see how the (somehow) specialized modular approach differs from a non-modular one.

We start by writing a couple of functions in the traditional way, as following:

function doAddition(num1, num2){
  return num1 + num2;
}

function doSubtraction(num1, num2){
  var result = null;
  if(num1 > num2){
  result = num1 - num2;

  }else{
    result = num2 - num1; 
  }
  return result;
}

console.log(doAddition(3,2)); // displays 5

console.log(doSubtraction(3,2)); // displays 1

As you can see in the above code, we have two independent functions for doing simple additions and subtractions and there is no relation between the two, other than the fact that they both operate on the two passed-in numbers ...