async promise

async-promise.js

// Async using promise 
var addB = function (a, b) {
  return new Promise((resolve, reject) => {
    setTimeout (() => { 
      resolve(a + b); 
    }, 0);
  });
};

// How to use it :D
addB(2, 3).then((result) => {
  console.log(result);
});

// No Callback Hell :)
addB(1, 1)
  .then((r) => addB(r, 1))
  .then((r) => addB(r, 1))
  .then((r) => addB(r, 1))
  .then((r) => addB(r, 1))
  .then((r) => addB(r, 1))
  .then((r) => addB(r, 1))
  .then((r) => {
    console.log(r)
  });

// You can also use Promise all to aggregate the result of multiple promise actions
var p1 = addB(2, 3)
var p2 = addB(2, 3)
var p3 = addB(2, 3)
Promise.all([p1, p2, p3]).then(([r1, r2, r3]) => {
  console.log(r1, r2, r3)
})