They use coffeescript's class inheritance. Here's the JS that compiles down to: ...

		MatthewPhillips on Aug 25, 2011 \| parent \| context \| favorite \| on: Announcing the first release of batman.js They use coffeescript's class inheritance. Here's the JS that compiles down to: http://jashkenas.github.com/coffee-script/#classes If they showed JS examples it would instantly turn everyone off. Trust me, you do NOT want to use this with JS.