cross-posted from: https://lemmy.stad.social/post/7709

Just pushed this to Github and Rubygems. I use this for my Ruby editor. It parses the GtkSourceView style XML files if you have GtkSourceView installed, and instantiates Rouge themes for them (Rouge is used by e.g. Gitlab) so you get access to some more themes. It's not perfect because it needs to try to map token types between the GtkSourceView and Rouge lexers, but overall works pretty well.