A major mode for editing OCaml code (see ) in Emacs. Some of its major features include: - syntax highlighting (font lock); - automatic indentation; - querying the type of expressions (using compiler generated annot files); - running an OCaml REPL within Emacs; - scans declarations and places them in a menu. The original indentation code was the work of Ian T Zimmerman and was adapted for OCaml by Jacques Garrigue in July 1997.