Use lexical-binding in nroff-mode.el

* lisp/textmodes/nroff-mode.el: Use lexical-binding.  Remove
redundant :group args.

diff --git a/lisp/textmodes/nroff-mode.el b/lisp/textmodes/nroff-mode.el
index 896578513cfb143a789e05723dca59d666b4c75b..fe70e925b05f76a40e1e53697b96722694b21114 100644 (file)
--- a/lisp/textmodes/nroff-mode.el
+++ b/lisp/textmodes/nroff-mode.el
@@ -1,4 +1,4 @@
-;;; nroff-mode.el --- GNU Emacs major mode for editing nroff source
+;;; nroff-mode.el --- GNU Emacs major mode for editing nroff source  -*- lexical-binding: t -*-
 
 ;; Copyright (C) 1985-1986, 1994-1995, 1997, 2001-2021 Free Software
 ;; Foundation, Inc.
@@ -43,7 +43,6 @@
 
 (defcustom nroff-electric-mode nil
   "Non-nil means automatically closing requests when you insert an open."
-  :group 'nroff
   :type 'boolean)
 
 (defvar nroff-mode-map
@@ -111,7 +110,7 @@
    ;; arguments in common cases, like \f.
    (concat "\\\\"                    ; backslash
         "\\("                        ; followed by various possibilities
-        (mapconcat 'identity
+         (mapconcat #'identity
                    '("[f*n]*\\[.+?]" ; some groff extensions
                      "(.."           ; two chars after (
                      "[^(\"#]"       ; single char escape
@@ -119,13 +118,11 @@
         "\\)")
    )
   "Font-lock highlighting control in `nroff-mode'."
-  :group 'nroff
   :type '(repeat regexp))
 
 (defcustom nroff-mode-hook nil
   "Hook run by function `nroff-mode'."
-  :type 'hook
-  :group 'nroff)
+  :type 'hook)
 
 ;;;###autoload
 (define-derived-mode nroff-mode text-mode "Nroff"