chinmay185

getUser("tom").then(function(user) {
  getTweets(user).then(function(tweets) {
    updateTimeline(tweets)
      .then(function() {
        console.log("done");
      });
  });
});

chinmay185

getUser("tom")
  .then(getTweets)
  .then(updateTimeline)
  .then(function(){
    console.log("done");
  });

chinmay185

fetchUser(username1)
  .then(function(user1) {
    fetchUser(username2)
      .then(function(user2) {
        makeFriends(user1, user2);
      });
});

chinmay185

var q = require("q");

// v1
q.all([getUser(username1), getUser(username2)])
  .then(function(users) {
    makeFriends(users[0], users[1]);
  });

// v2 (even better)
q.all([fetchUser(username1), fetchUser(username2)])

chinmay185

var q = require("q");

var getUser = function(username) {
  return q.delay(500).then(function(){
    return username + " user";
  });
};

var getTweets = function(user) {
  return q.delay(500).then(function(){

chinmay185

var getUserEmail = function(username) {
  var deferred = q.defer();
  userRepository.find(username) // assume this returns a promise
    .then(function(user){
      deferred.resolve(user.email);
    });
  return deferred.promise;
};

getUserEmail("emma").then(console.log);

chinmay185

var getUserEmail = function (username) {
  return userRepository.find(username).then(function (user) {
    return user.email;
  });
};

getUserEmail("emma").then(console.log);

chinmay185

var Promise = require("bluebird");
var apiUrls = ["url1", "url2", "url3"];

var request = function(url) {
  // request the rate limited api (returns a promise)
};
var saveResponse = function(response) {
  // save response to file/db (returns a promise)
};

chinmay185

var Promise = require("bluebird");
var productIds = ["productId1", "productId2", "productId3"];

var getProductsFromDb = function(productId) {
  // returns a promise of product
}

var productPromises = productIds.map(getProductFromDb);

Promise.all(productPromises).then(function(products) {

chinmay185

var Promise = require("bluebird");
var fileParts = ["http://myfiles.com/file1/part1", 
		"http://myfiles.com/file1/part2", 
		"http://myfiles.com/file1/part3"];

var fetchPart = function(partUrl) {
  // returns the promise of the part of a file
};

var filePartPromises = fileParts.map(fetchPart);