This function helps you save already calculated function's value to the array and prevents you from loading the function again and again. Credit to Douglas Crockford.

memoizer.js

/*
Memoizer function takes an initial memo array and fundamental function. 
It returns a shell function that manages the memo store and that calls the functamental function as needed. 
We pass the shell function and the function's parameters to the fundamental function.
For example: Fibonacci series creater.
var fibonacci = memoizer([0,1], function(shell, n){
  return shell(n-1) + shell(n-2);
});
*/

var memoizer = function(memo, fundamental){
    var shell = function(n){
      var result = memo[n];
      if(typeof result !== 'number'){
        result = fundamental(shell, n);
        memo[n] = result;
      }
      return result;
    };
    return shell;
  };