Promise chaining example (promised-io)

promise-example.js

var Deferred = require("promised-io/promise").Deferred;

// 1st function with promise
var function1 = function(bool){
  var deferred = new Deferred();
  
  //add timeout for fun
  setTimeout(function(){
    bool ? deferred.resolve('yay1') : deferred.reject('no1');
  }, 300);
  
  return deferred.promise;
};

// 2nd function with promise
var function2 = function(bool){
  var deferred = new Deferred();
  bool ? deferred.resolve('yay2') : deferred.reject('no2');
  return deferred.promise;
};

function1(true).then(function (first) {
  console.log(first);
  // To chain promises you need to return other promise here
  return function2(false);
}).then(function (second) {
  console.log(second);
}, function (err) {
  // Here we get error from both chained functions
  console.log(err)
});