Initial version of able-script-mode

.gitignore

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+*~

README.md

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+# AbleScript Mode
+![Discord](https://img.shields.io/discord/831368967385120810)
+
+[Able Script Book](https://ablecorp.us/able-script-the-book/)
+
+Emacs major mode for editing AbleScript files.
+
+## Features
+- Syntax highlighting of keywords, variables and base52 numbers
+- Automatic indentation

able-script-mode.el

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+;;; able-script-mode -- Able script mode
+
+;;; Commentary:
+
+;; Major mode for able-script code, by Alex Bethel. See
+;; https://github.com/AbleCorp/able-script.
+
+;;; Code:
+
+(defgroup able-script-mode nil
+  "Support for AbleScript code."
+  :link '(url-link "https://github.com/AbleCorp/able-script")
+  :group 'languages)
+
+(defcustom able-script-indent-offset 4
+  "Indent AbleScript code by this number of spaces per level."
+  :type 'integer
+  :group 'able-script-mode)
+
+;; Adapted from
+;; gemini://gemini.omarpolo.com/post/writing-a-major-mode.gmi
+;;
+;; TODO: this behaves strangely sometimes when point is at the
+;; beginning of the line; re-write this to work like other major
+;; modes.
+(defun able-script-indent-line ()
+  "Indent current line."
+  (let (indent
+        boi-p                           ;begin of indent
+        move-eol-p
+        (point (point)))
+    (save-excursion
+      (back-to-indentation)
+      (setq indent (car (syntax-ppss))
+            boi-p (= point (point)))
+      ;; don't indent empty lines
+      (when (and (eq (char-after) ?\n)
+                 (not boi-p))
+        (setq indent 0))
+      ;; check whether we want to move
+      (when boi-p
+        (setq move-eol-p t))
+      ;; decrement the indent if the first character on the line is a
+      ;; closer.
+      (when (or (eq (char-after) ?\))
+                (eq (char-after) ?\})
+                (eq (char-after) ?\]))
+        (setq indent (1- indent)))
+      ;; indent the line.
+      (delete-region (line-beginning-position)
+                     (point))
+      (indent-to (* able-script-indent-offset indent)))
+    (when move-eol-p
+      (back-to-indentation))))
+
+;; Using generic-mode for now because I'm lazy.
+(define-generic-mode
+    able-script-mode
+  '("owo")
+  '("aint"
+    "functio"
+    "bff"
+    "var"
+    "print"
+    "read"
+    "melo"
+    "T-Dark"
+    "if"
+    "loop"
+    "break"
+    "rlyeh"
+    "rickroll"
+    "true"
+    "false"
+    "always"
+    "sometimes"
+    "never")
+  '(
+    ;; Draw base-52 numbers in the `warning' face, because if you're
+    ;; anything like me you usually don't mean to use them.
+    ("\\b[[:alpha:]]\\b" 0 font-lock-warning-face)
+    ("\\bvar \\([[:alnum:]_]*\\)" 1 font-lock-variable-name-face)
+    ("\\bfunctio \\([[:alnum:]_]*\\)" 1 font-lock-function-name-face))
+  '(".*\\.able")
+  (list
+   (function
+    (lambda ()
+      (setq-local indent-line-function #'able-script-indent-line))))
+  "Able-script mode")
+
+(provide 'able-script-mode)
+;;; able-script-mode.el ends here