An Interactive MusicXML Element Tree

When writing my tutorial series on MusicXML, I found myself regularly clicking around the MusicXML element tree on the W3C docs site, dearly wishing I could individually expand and collapse the elements to better explore the spec and get a feel of how everything fit together. Once you're a few levels deep it's easy to lose your conceptual grasp on where you are and how the elements (the many many elements!) relate to each other.

In response I've put together the below prototype, a version of which I'm hopeful will eventually make its way into the official documentation. If you've stumbled upon this and are interested in exploring the spec, I hope you find it helpful!