ex/ javascript revealing module pattern

gistfile1.js

var calculator = function() {
  var numbers = [4,2,5,7],
  sum = 0
  var getSum = function() {
    for(var x = 0; x < numbers.length; x++){
      sum += numbers[x];
    }
    return sum;
  };
  var sayHello = function() {
    console.log("HIIiiii");
  }
  sayHello();

  return {
    title: "sum up numbers",
    sumfn: getSum, 
  }

};