The new home of Lua mode for Emacs (WARNING: only master is guaranteed to preserve its history, use other branches at your own risk)
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Lua mode

lua-mode is a major mode for editing Lua sources in Emacs. After a rather long hiatus, it's back in active development stage, so make sure to visit homepage frequently enough.

If you have a problem or a suggestion about lua-mode, please, let me know about it via github's Issue Tracker.


To install, just copy lua-mode.el into a directory on your load-path (and optionally byte-compile it). To set up Emacs to automatically edit files ending in .lua or with a lua hash-bang line using lua-mode add the following to your init file:

(autoload 'lua-mode "lua-mode" "Lua editing mode." t)
(add-to-list 'auto-mode-alist '("\\.lua$" . lua-mode))
(add-to-list 'interpreter-mode-alist '("lua" . lua-mode))


lua-mode supports c-mode style formatting and sending of lines/regions/files to a Lua interpreter. An interpreter (see variable lua-default-application) will be started if you try to send some code and none is running. You can use the process-buffer (named after the application you chose) as if it were an interactive shell. See the documentation for comint.el for details.

Lua-mode also works with Hide Show minor mode (see hs-minor-mode).


Currently, there're a lot of features that need fixing (or reimplementing), including but not limited to:

  1. implementing autotesting of indentation engine
  2. supporting line-continuation commas
  3. fixing close-brace/paren positioning
  4. fix syntax handling of multiline comments/literals (including both highlighting & indentation)
  5. implementing a crisp scheme of customizing the way lua-mode indents the code
  6. cleaning up existing code
  7. extending docs & comments

CEDET/Semantic integration

Also, there's a rather distant goal to integrate lua-mode with cedet's semantic. This would mean an almost complete rewrite, but I think the challenge is worth it. There's a slightest concern about the overhead brought by this dependency, but semantic is already being shipped with Emacs, so there might be no problem after all.

Use wisent-generated grammar

First stage would be to rewrite syntax handling with help of semantic/wisent-generated parser based on the actual Lua grammar. Currently, syntax analysis is done ad-hoc and, despite the model is oversimplified and doesn't treat corner situation well, it's still very tricky and really hard to grasp.

Extend cedet/semantic facilities onto Lua

And there's the cherry on the pie: after completing the wisent-generated parser, the next step will be to provide semantic with all the information it needs to do it's magic of code analysis and generation.