How to do it...

1. Open your command line application and navigate to the directory containing the 02-creating-client-bundles package.
2. Start the Python HTTP server.
3. Update the main.js file to use the Array.prototype.values method, and use for..of to loop over the resulting iterator:

import { atlas, saturnV } from './rockets/index.js' 
 
export function main () { 
  const rockets = [saturnV, atlas];
  for (const rocket of rockets.values()) {
    rocket.launch();
  } 
}  

4. Install the Babel Polyfill package:

    npm install --save babel-polyfill  

5. To shim the bundle, update the webpack.config.js file to add Babel Polyfill to the entry point:

const path = require('path'); 
 
module.exports = { 
  entry: ['babel-polyfill', './index.js'], 
  output: { 
    filename: 'bundle.js', 
    path: path.resolve(__dirname) 
  } 
};  

6. To shim ES modules, you'll need to import the file directly. Update index.html to import the polyfill:

<!-- index.html --> 
<script type="module"> 
  import './node_modules/babel-polyfill/dist/polyfill.min.js'; 
  import { main } from './main.js'; 
  main(); 
</script>  

7. Now open a browser, open the Developer Console, and visit the URL:
    http://localhost:8000/.
8. Whether the browser supports Array.prototype.values or not, the code should run and display output as follows: