Simple Promise example from the web

getTweetsFor.js

// Source: https://gist.github.com/domenic/3889970
// Just sticking the parts in one spot and playing with them.

function getTweetsFor() {
  var ajaxOptions = {
    url: '...',
    ...
  };

  return new RSVP.Promise(function(resolve, reject) {
    ajaxOptions.success = function(json) { resolve(json); };
    ajaxOptions.error = function(jqXHR) {
      if (jqXHR && typeof jqXHR === 'object') {
        jqXHR.then = null;
      }
      reject(jqXHR);
    }

    $.ajax(ajaxOptions);
  });
}

getTweetsFor("domenic") // promise-returning async function
    .then(function (tweets) {
        var shortUrls = parseTweetsForUrls(tweets);
        var mostRecentShortUrl = shortUrls[0];
        return expandUrlUsingTwitterApi(mostRecentShortUrl); // promise-returning async function
    })
    .then(doHttpRequest) // promise-returning async function
    .then(
        function (responseBody) {
            console.log("Most recent link text:", responseBody);
        },
        function (error) {
            console.error("Error with the twitterverse:", error);
        }
    );