cssAudio - Activefile-genericCSS - ActiveGeneric - ActiveHTML - ActiveImage - ActiveJS - ActiveSVG - ActiveText - Activefile-genericVideo - ActiveLovehtmlicon-new-collectionicon-personicon-teamlog-outoctocatpop-outspinnerstartv

Pen Settings

CSS Base

Vendor Prefixing

Add External Stylesheets/Pens

Any URL's added here will be added as <link>s in order, and before the CSS in the editor. If you link to another Pen, it will include the CSS from that Pen. If the preprocessor matches, it will attempt to combine them before processing.

Quick-add: + add another resource

Add External Scripts/Pens

Any URL's added here will be added as <script>s in order, and run before the JavaScript in the editor. You can use the URL of any other Pen and it will include the JavaScript from that Pen.

Quick-add: + add another resource

Code Indentation


Save Automatically?

If active, Pens will autosave every 30 seconds after being saved once.

Auto-Updating Preview

If enabled, the preview panel updates automatically as you code. If disabled, use the "Run" button to update.

              This demo uses Babel for es2015 compilation and Promises, and superagent for requests.
  <button id="run">Run</button>
  <pre id="log"></pre>
              // An example async pipeline, using a demo API
document.getElementById('run').addEventListener('click', (evt) => {
  iteratePromises(function* () {
    log('Requesting list of posts');
    let postsResponse = yield superagent.get(
    log('Requesting author of first post');
    let userResponse = yield superagent.get(
      'http://jsonplaceholder.typicode.com/users/' + postsResponse.body[0].userId);
    log('Post Author: ' + userResponse.body.name);

// This helper takes a generator and resolves each yielded promise in turn, passing
// each result back as the `yield` response.
function iteratePromises(Generate) {
  let generator = Generate(); // store the iterable generator object
  function iterate(yieldResponse) {
    let iterated = generator.next(yieldResponse); // fire the next iterable step
    if (!iterated.done && typeof iterated.value.then === 'function') {
      // if the iterable yields a promise, wait for it to resolve and iterate again
      iterated.value.then((response) => iterate(response));
  iterate(); // kick off the generator

// A simple reverse-chronological logger
const log = (function (){
  const logTarget = document.getElementById('log');
  let logNumber = 1;
  return function (msg) {
    logTarget.innerHTML = logNumber++ + ' >> ' + msg + '\n' + logTarget.innerHTML;
Loading ..................