lalohao / babylon-mode

An emacs mode for highlighting JavaScript using the babylon parser

Babylon mode (babylon-mode)

An emacs mode for highlighting JavaScript using the babylon parser

Instead of trying to re-implement a JS parser in elisp like js2-mode, or trying to parse JS and JSX using regexes like web-mode, we try to offload a bunch of the actual parsing work onto some code that we know actually works: babylon. Babylon is the parser that babel uses, so we can be very confident that it will successfully parse any JavaScript we throw at it! All we need to do is traverse the tree, highlight things that we want, and we're good to go.

Currently, this comes at the significant downside that it is painfully slow and very error-prone. But I'm working on it, and hopefully it will get to the point that it will be useful for other people.

Install

Clone this repo somewhere

% git clone https://github.com/xymostech/babylon-mode.git

Add the path to load-path in your .emacs.el:

(add-to-list 'load-path "/path/to/babylon-mode")

Then, add an autoload for loading babylon-mode, and optionally add babylon-mode to auto-mode-alist:

(autoload 'babylon-mode "babylon-mode" nil t)

(add-to-list 'auto-mode-alist '("\\.jsx$" . babylon-mode))
(add-to-list 'auto-mode-alist '("\\.js$" . babylon-mode))

Usage

Visit a .js or .jsx file, or manually run babylon-mode:

babylon-mode

Maintainer

• xymostech

Contribute

This is the first large amount of elisp that I've written (aside from my .emacs.el), so I apologize for any elisp faux pas I have committed. If you find this useful and have any ideas for improvement, I'd love to hear! Issues pointing out how broken things currently are are probably not useful, because the whole thing is pretty broken.

In other words:

• Ask questions in github issues
• PRs are welcome, especially to improve the elisp, but huge code refactorings are not useful. I'm trying to learn elisp and continue working on this, so huge changes would put a damper on it.

License

MIT