commit caaad6ea29f61fa8815da83cee9af1eab19c63f9
from: Omar Polo <op@omarpolo.com>
date: Sun Nov 07 13:54:24 2021 UTC

add a68 group and replace defvar with defcustom

commit - 8621ed2a1e4566dd7023d1f7fa4226e5353a96f8
commit + caaad6ea29f61fa8815da83cee9af1eab19c63f9
blob - 34605fe3567f1b56a62a6921a6dc9ebda5762786
blob + b0bf5a8cc390b1260861ae172471c8a6911660bf
--- a68-mode.el
+++ a68-mode.el
@@ -47,9 +47,16 @@
 (eval-when-compile
   (require 'rx))
 
-(defvar a68-indent-level 3
-  "Indentation step for Algol 68.")
+(defgroup a68 nil
+  "Major mode for editing Algol68 code."
+  :prefix "a68-"
+  :group 'languages)
 
+(defcustom a68-indent-level 3
+  "Indentation step for Algol 68."
+  :type 'integer
+  :safe #'integerp)
+
 (defvar a68-mode-hook '()
   "Hook run when entering Algol68 mode.")