From fdf1c7c32fb088ddb470353d4eb141ef9017a89f Mon Sep 17 00:00:00 2001
From: Stefan Monnier <monnier@iro.umontreal.ca>
Date: Sat, 27 Oct 2001 07:42:11 +0000
Subject: [PATCH] (text-mode): Use define-derived-mode.
 (toggle-text-mode-auto-fill): Use derived-mode-p.

---
 lisp/textmodes/text-mode.el | 24 +++++++-----------------
 1 file changed, 7 insertions(+), 17 deletions(-)

diff --git a/lisp/textmodes/text-mode.el b/lisp/textmodes/text-mode.el
index 9e89cb17e30..bb15f43cacc 100644
--- a/lisp/textmodes/text-mode.el
+++ b/lisp/textmodes/text-mode.el
@@ -66,18 +66,13 @@ inherit all the commands defined in this map.")
   (define-key text-mode-map "\eS" 'center-paragraph))
 
 
-(defun text-mode ()
+(define-derived-mode text-mode nil "Text"
   "Major mode for editing text written for humans to read.
 In this mode, paragraphs are delimited only by blank or white lines.
 You can thus get the full benefit of adaptive filling
  (see the variable `adaptive-fill-mode').
 \\{text-mode-map}
 Turning on Text mode runs the normal hook `text-mode-hook'."
-  (interactive)
-  (kill-all-local-variables)
-  (use-local-map text-mode-map)
-  (setq local-abbrev-table text-mode-abbrev-table)
-  (set-syntax-table text-mode-syntax-table)
   (make-local-variable 'paragraph-start)
   (setq paragraph-start (concat page-delimiter "\\|[ \t]*$"))
   (if (eq ?^ (aref paragraph-start 0))
@@ -85,10 +80,7 @@ Turning on Text mode runs the normal hook `text-mode-hook'."
   (make-local-variable 'paragraph-separate)
   (setq paragraph-separate paragraph-start)
   (make-local-variable 'indent-line-function)
-  (setq indent-line-function 'indent-relative-maybe)
-  (setq mode-name "Text")
-  (setq major-mode 'text-mode)
-  (run-hooks 'text-mode-hook))
+  (setq indent-line-function 'indent-relative-maybe))
 
 (defun paragraph-indent-text-mode ()
   "Major mode for editing text, with leading spaces starting a paragraph.
@@ -136,16 +128,14 @@ This is how `toggle-text-mode-auto-fill' knows which buffers to operate on."
 This command affects all buffers that use modes related to Text mode,
 both existing buffers and buffers that you subsequently create."
   (interactive)
-  (let ((enable-mode (not (memq 'turn-on-auto-fill text-mode-hook)))
-	(buffers (buffer-list)))
+  (let ((enable-mode (not (memq 'turn-on-auto-fill text-mode-hook))))
     (if enable-mode
 	(add-hook 'text-mode-hook 'turn-on-auto-fill)
       (remove-hook 'text-mode-hook 'turn-on-auto-fill))
-    (while buffers
-      (with-current-buffer (car buffers)
-	(if text-mode-variant
-	    (auto-fill-mode (if enable-mode 1 0))))
-      (setq buffers (cdr buffers)))
+    (dolist (buffer (buffer-list))
+      (with-current-buffer buffer
+	(if (or (derived-mode-p 'text-mode) text-mode-variant)
+	    (auto-fill-mode (if enable-mode 1 0)))))
     (message "Auto Fill %s in Text modes"
 	     (if enable-mode "enabled" "disabled"))))
 
-- 
2.39.5