That MDN article is fairly limited - a whole javascript syntax for querying documents came with it: https://help.adobe.com/en_US/as3/dev/WS5b3ccc516d4fbf351e63e

That MDN article is fairly limited - a whole javascript syntax for querying documents came with it: https://help.adobe.com/en_US/as3/dev/WS5b3ccc516d4fbf351e63e3d118a9b90204-7e72.html https://help.adobe.com/en_US/as3/dev/WS5b3ccc516d4fbf351e63e... In the end we jumped from ES3 to ES5, skipping all of E4X. I wonder if we're better off.