ndnguru

var executionTimes = []; // an array to hold the time stamps at various stages, during callbacks

// this function simulates an async function to get the X value
function getXValue(callback) {
  var num = ~~(Math.random() * 100); //get a number between 0-100 and coerce to an Integer using '~~'
  console.log('X will be: ', num);
  var delay = ~~(Math.random() * 5000); // set a random delay btw 0-5 sec
  console.log('X Delay (in ms): ' + delay);

  //now we set a timeout to invoke to callback function