Day: February 18, 2014

JavaScript’s function.apply() function..

As seen in A Re-Introduction To JavaScript

JavaScript functions are objects. So, when we declare a function, we get a bunch of other stuff for free! Take, the apply() method, which lets us pass an array into the arguments list of a method! I explain:

Say we have a function that calculates averages from a list of numbers passed into it:

function getAverage() {
  total = 0;
  for (i in arguments) {
    total += arguments[i];
  }
  return total / arguments.length;
}

We can now call this method to get the average of one or more numbers. Calling:
getAverage(4,2,3,5);
returns 3.5

We can also:
getAverage.apply(null, [4,2,3,5]);
which also returns 3.5!

Also, goes to show that functions are indeed Objects!