This is just a quick experiment to play around with the idea of compiling .html files for custom elements into plain .js JavaScript files. JavaScript files might be an interesting packaging medium for custom elements:

• You could combine a .js file with custom elements with other .js files (with polymer.js, among others) to reduce the number of resources which must be fetched for a page to load.
• JavaScript files could be optimized with existing techniques (e.g., Google's Closure compiler) to, for example, eliminate dead code for unused elements.
• Experimentation might point to better performance. Currently the compiler just sets innerHTML, but it could just as easily output appendChild() calls. It could also take care of things like identifying Polymer's this.$.foo automatic node references or MDV bindings at compile time.

This is just a proof of concept. The compiler doesn't register elements as Polymer elements yet (it uses document.register directly), and doesn't handle the full range of element syntax: attributes, "extends=", etc.

> npm install

Edit the demo element at demo/test-element.html, then run grunt to recompile. The demo is visible at http://JanMiksovsky.github.io/compel/demo.