Emacs inko-mode

[MarcusE1W]

Hi.
Maybe there is interest from a few people in an Emacs mode for Inko.
I have created a very simple version based on this tutorial

Here is the Code for inko-mode.el:

;; define default for tab-width
  (defvar inko-tab-width 2 "Width of a tab for InkoL mode")

;; == create the list for font-lock. ==
;; == each category of keyword is given a particular face ==
(setq inko-font-lock-keywords
      (let* (
            ;; define several category of keywords
            (x-structual-keywords '("fn" "if" "loop" "import" "class" "for" "trait" "while" "match" "recover" "else" "impl" "throw" "try?" "try!" "try" "recover" ))
            (x-types '("Array" "Bool" "ByteArray" "Channel" "Float" "Int" "Map" "Nil" "Option" "Result" "String" "Never" "true" "false" ))
            (x-events '("async" "ref" "mut" "extern" "pub" "self" "enum" "static" "builtin" "nil" "uni"))
            (x-functions '("case" "as" "let" "return" "move" "next" "and" "or" "break"))

            ;; generate regex string for each category of keywords
            (x-structual-keywords-regexp (regexp-opt x-structual-keywords 'words))
            (x-types-regexp (regexp-opt x-types 'words))
            (x-events-regexp (regexp-opt x-events 'words))
            (x-functions-regexp (regexp-opt x-functions 'words)))

        `(
          (,x-types-regexp . 'font-lock-type-face)
          (,x-events-regexp . 'font-lock-builtin-face)
          (,x-functions-regexp . 'font-lock-function-name-face)
          (,x-structual-keywords-regexp . 'font-lock-keyword-face)
          ;; note: order above matters, because once colored, that part won't change.
          ;; in general, put longer words first
          )))

;; == define inko-mode ==
(define-derived-mode inko-mode prog-mode "Inko mode"
  "Simple Major mode for editing the Inko language"

  ;; code for syntax highlighting
  (setq font-lock-defaults '((inko-font-lock-keywords)))

    ;; when there's an override for tabs, use it
    (when inko-tab-width
      (setq tab-width inko-tab-width))
  
    ;; for comments
    (setq comment-start "#")
    (setq comment-end "")
  
    (modify-syntax-entry ?# "< b" inko-mode-syntax-table)
    (modify-syntax-entry ?\n "> b" inko-mode-syntax-table)
  
  )

;;;###autoload
(add-to-list 'auto-mode-alist '("\\.inko\\'" . inko-mode))

;; add the mode to the `features' list
(provide 'inko-mode)

To test:

1. M-x eval-buffer in inko-mode.el
2. M-x inko-mode in a .inko code buffer

To install:

1. download inko-mode.el to /your/path
2. add line to Emacs init.el:

(load-file "/full/your/path/inko-mode.el")

[yorickpeterse]

@MarcusE1W Thanks! Is this something that could be turned into an easy to use plugin like https://github.com/inko-lang/inko.vim?

Also small nitpick: Inko uses 2 spaces per indentation instead of 4 😃

[MarcusE1W]

I have changed the indentation to 2, thanks for the hint.

To install you need to download the file somewhere, e.g. ~/.emacs.d/install and then add a line to your init.elconfig file as mentioned on the top.
The code above is a package/plugin already.

[yorickpeterse]

@MarcusE1W Sorry! What I meant was to turn it into an actual repository such that people can clone it, following whatever the usual conventions are for Emacs packages, though I'm not sure what the usual approach is for emacs packages 😃