Tips: Syntax highlight for inline ~L liveview code in emacs

Install web-mode and mmm-mode first and put this in your config file:

(require 'mmm-mode)
(require 'web-mode)
(setq mmm-global-mode 'maybe)
(setq mmm-parse-when-idle 't)
(setq mmm-set-file-name-for-modes '(web-mode))
(custom-set-faces '(mmm-default-submode-face ((t (:background nil)))))
(let ((class 'elixir-eex)
    (submode 'web-mode)
    (front "^[ ]+~L\"\"\"")
    (back "^[ ]+\"\"\""))
  (mmm-add-classes (list (list class :submode submode :front front :back back)))
  (mmm-add-mode-ext-class 'elixir-mode nil class))

(define-advice web-mode-guess-engine-and-content-type (:around (f &rest r) guess-engine-by-extension)
  (if (and buffer-file-name (equal "ex" (file-name-extension buffer-file-name)))
      (progn (setq web-mode-content-type "html")
         (setq web-mode-engine "elixir")
    (apply f r)))



I was unable to get syntax highlighting to update when modifying the LiveView sigil so I put together a similar solution based on polymode (instead of mmm-mode).


Next version of Neovim (0.5.0) uses the tree-sitter parser for syntax highlighting. Does anyone know how to configure tree-sitter to syntax-highlight embedded sub-languages like leex and sub-sub languages like surface?


Before tree-sitter will be usable with Elixir someone will have to write a tree-sitter elixir grammar. I’m aware of a few attempts, but as far as I’m aware none of them are close to being usable.

Most recent semi-active projects:

Older stalled projects:

I too am very interested in having tree sitter grammars (and even took a very short stab at writing one). Overall I like tree-sitter’s approach over a large number of brittle regular expressions.