Is there any way we can use XML (ie. HTML with invented tag names (and attribute names)), along with a DSL-like converter, to convert various bits of XML into HTML?

The proximate inspiration for this was my thoughts about trying to document my Tasker rules that I created, and using systematic styles for various bits of information (eg. one color for strings, another color for events... one left-border-color for profiles, another left-border-color for tasks)

possible Perl implementations

possible Node.js implementations