Hans Fugal has released a Vim syntax highlighting file for Relax NG compact syntax (RNC). It joins a couple of other options available for working with and viewing syntax-highlighted RNC schema instances: an Emacs mode and a set of stylesheets for generating HTML versions of RNC schemas.

All three mechanisms use highlighting which gives prominence to the most important information in any schema: the element and attribute names -- and in the case of RNC schemas, the named-pattern names (similar to DTD parameter entity names).

Figure 1: RNC in Vim

Figure 2: RNC in Emacs

Figure 3: RNC in HTML

The lean-ness of the RNC syntax combined with the syntax highlighting makes for some extremely readable schemas.

Related links

• RELAX NG's Compact Syntax (XML.com RNC tutorial from Mike Fitzgerald)

• RELAX NG Compact Syntax Tutorial (James Clark et al)

• RELAX NG Compact Syntax (specification)

• Introduction to RELAX NG (book; work in progress from Eric van der Vlist)

• The Design of RELAX NG (James Clark)

• A Triumph of Simplicity: James Clark on Markup Languages and XML (article from Dr. Dobb's Journal)