This ia based on the grammar included in OCaml and Reason IDE, which unfortunately is hand-tuned in a rather haphazard way to be "optimized" for a few of the original author's preferred themes, to the detriment of everything else. This fork attempts to provide a more coherent grammar that properly distinguishes different tokens so that they can be properly selected for highlighting. In effect, this should provide a better default for most themes (except, of course, the select few the original grammar was hand-tuned for) and moves the repsonsibility of optimizing highlighting for specific languages from the grammar to each theme, where it should be to remain maintainable (and quite frankly just plain sane).
Thanks to Darrin Morrison for creating the original grammar this is based on.