WARNING There is a built-in Elixir mode with tree-sitter support from Emacs 30+ that can also be used with Emacs 29 This repository is for an older elixir-mode built with SMIE (Simple Minded Indentation Engine) which is not as advanced as tree-sitter for a language like Elixir.
Provides font-locking, indentation and navigation support for the Elixir programming language.
elixir-mode is available on NON-GNU ELPA,
MELPA STABLE and MELPA.
package.el is the built-in package manager in Emacs.
You can install elixir-mode with the following command:
M-x package-install [RET] elixir-mode [RET]
or by adding this bit of Emacs Lisp code to your Emacs initialization file
(.emacs or init.el):
(unless (package-installed-p 'elixir-mode)
(package-install 'elixir-mode))If the installation doesn't work try refreshing the package list:
M-x package-refresh-contents [RET]
Keep in mind that MELPA packages are built automatically from
the master branch, meaning bugs might creep in there from time to
time. Never-the-less, installing from MELPA is the recommended way of
obtaining Elixir-Mode.
MELPA Stable contains packages released from our tags.
Since Emacs 29, use-package is a built-in feature. For versions prior to 29
one can also install it from MELPA (and MELPA Stable).
To install elixir-mode using use-package one can:
(use-package elixir-mode
:ensure t)Command (For the M-x prompt.) |
Description |
|---|---|
elixir-mode |
Switches to elixir-mode. |
elixir-mode-open-github |
Open the GitHub page for Elixir. |
elixir-mode-open-elixir-home |
Go to Elixir README in the browser. |
elixir-mode-open-docs-master |
Open the Elixir documentation for the master. |
elixir-mode-open-docs-stable |
Open the Elixir documentation for the latest stable release. |
elixir-mode-show-version |
Print version info for elixir-mode. |
Any file that matches the glob *.ex[s] or *.elixir is
automatically opened in elixir-mode, but you can change this
functionality easily.
;; Highlights *.elixir2 as well
(add-to-list 'auto-mode-alist '("\\.elixir2\\'" . elixir-mode))Keymaps can be added to the elixir-mode-map variable.
Smartparens has direct support for Elixir.
Alternatively, if you want to use ruby-end-mode, you can add the following to your elixir-mode-hook:
(add-to-list 'elixir-mode-hook
(defun auto-activate-ruby-end-mode-for-elixir-mode ()
(set (make-variable-buffer-local 'ruby-end-expand-keywords-before-re)
"\\(?:^\\|\\s-+\\)\\(?:do\\)")
(set (make-variable-buffer-local 'ruby-end-check-statement-modifiers) nil)
(ruby-end-mode +1)))This package is tested only with a single version of OTP and 3 versions of Elixir. Please, always report versions (Emacs, Elixir and Erlang/OTP) when raising issues.
You can use web-mode.el to edit elixir templates (eex files).
mix.el provides a minor mode for integration with Mix, a build tool that ships with Elixir.
exunit.el provides ExUnit integration.
This mode can call mix for formatting code. When inside an elixir buffer, just type M-x elixir-format.
To automate that, you can add this command to the before-save hook.
;; Create a buffer-local hook to run elixir-format on save, only when we enable elixir-mode.
(add-hook 'elixir-mode-hook
(lambda () (add-hook 'before-save-hook 'elixir-format nil t)))To use a .formatter.exs you can either set elixir-format-arguments globally to a path like this:
(setq elixir-format-arguments (list "--dot-formatter" "/path/to/.formatter.exs"))or you set elixir-format-arguments in a hook like this:
(add-hook 'elixir-format-hook (lambda ()
(if (projectile-project-p)
(setq elixir-format-arguments
(list "--dot-formatter"
(concat (locate-dominating-file buffer-file-name ".formatter.exs") ".formatter.exs")))
(setq elixir-format-arguments nil))))In this example we use Projectile to determine if we are in a project and then set elixir-format-arguments accordingly.
Please note that this code snippet may cause unhappiness if there is no .formatter.exs file available.
Emacs supports font ligatures. For enabling it for Elixir you can add it to your configuration:
(add-hook
'elixir-mode-hook
(lambda ()
(push '(">=" . ?\u2265) prettify-symbols-alist)
(push '("<=" . ?\u2264) prettify-symbols-alist)
(push '("!=" . ?\u2260) prettify-symbols-alist)
(push '("==" . ?\u2A75) prettify-symbols-alist)
(push '("=~" . ?\u2245) prettify-symbols-alist)
(push '("<-" . ?\u2190) prettify-symbols-alist)
(push '("->" . ?\u2192) prettify-symbols-alist)
(push '("<-" . ?\u2190) prettify-symbols-alist)
(push '("|>" . ?\u25B7) prettify-symbols-alist)))
;; Or if you use use-packge
(use-package elixir-mode
:hook (elixir-mode . (lambda ()
(push '(">=" . ?\u2265) prettify-symbols-alist)
(push '("<=" . ?\u2264) prettify-symbols-alist)
(push '("!=" . ?\u2260) prettify-symbols-alist)
(push '("==" . ?\u2A75) prettify-symbols-alist)
(push '("=~" . ?\u2245) prettify-symbols-alist)
(push '("<-" . ?\u2190) prettify-symbols-alist)
(push '("->" . ?\u2192) prettify-symbols-alist)
(push '("<-" . ?\u2190) prettify-symbols-alist)
(push '("|>" . ?\u25B7) prettify-symbols-alist))))If you have issues with the formatter provided by this package, you can try using the format function of language servers. Elixir-ls supports this.
One way to configure this with eglot and use-package would be:
(use-package elixir-mode
:hook (elixir-mode . eglot-ensure)
(before-save . eglot-format))When you need different major modes in the SAME buffer, Emacs do not provide a standard way.
There is an external package that can help here by adding more than one major mode called poly-mode.
A possible configuration would be:
;; Assumes web-mode and elixir-mode are already set up
;;
(use-package polymode
:mode ("\.ex$" . poly-elixir-web-mode)
:config
(define-hostmode poly-elixir-hostmode :mode 'elixir-mode)
(define-innermode poly-liveview-expr-elixir-innermode
:mode 'web-mode
:head-matcher (rx line-start (* space) "~H" (= 3 (char "\"'")) line-end)
:tail-matcher (rx line-start (* space) (= 3 (char "\"'")) line-end)
:head-mode 'host
:tail-mode 'host
:allow-nested nil
:keep-in-mode 'host
:fallback-mode 'host)
(define-polymode poly-elixir-web-mode
:hostmode 'poly-elixir-hostmode
:innermodes '(poly-liveview-expr-elixir-innermode))
)
(setq web-mode-engines-alist '(("elixir" . "\\.ex\\'")))This mode is based on the Emacs mode by secondplanet.
Please read CONTRIBUTING.md for guidelines on how to contribute to this project.
Copyright © 2011-2017 Samuel Tonini, Matt DeBoard, Andreas Fuchs, secondplanet and contributors.
Distributed under the GNU General Public License, version 3
