X-Git-Url: https://code.delx.au/gnu-emacs/blobdiff_plain/e4ad5f9e5f7b0b98399c7912ce41eb362fde5c11..937640a621a4ce2e5e56eaecca37a2a28a584318:/lisp/emacs-lisp/easy-mmode.el

diff --git a/lisp/emacs-lisp/easy-mmode.el b/lisp/emacs-lisp/easy-mmode.el
index 069430a7aa..b6b91710ed 100644
--- a/lisp/emacs-lisp/easy-mmode.el
+++ b/lisp/emacs-lisp/easy-mmode.el
@@ -1,9 +1,11 @@
-;;; easy-mmode.el --- easy definition for major and minor modes.
+;;; easy-mmode.el --- easy definition for major and minor modes
 
-;; Copyright (C) 1997  Free Software Foundation, Inc.
+;; Copyright (C) 1997,2000,01,02,03,2004  Free Software Foundation, Inc.
 
-;; Author:  Georges Brun-Cottan <Georges.Brun-Cottan@inria.fr>
-;; Maintainer:  Stefan Monnier <monnier@gnu.org>
+;; Author: Georges Brun-Cottan <Georges.Brun-Cottan@inria.fr>
+;; Maintainer: Stefan Monnier <monnier@gnu.org>
+
+;; Keywords: extensions lisp
 
 ;; This file is part of GNU Emacs.
 
@@ -33,11 +35,11 @@
 ;; For each mode, easy-mmode defines the following:
 ;; <mode>      : The minor mode predicate. A buffer-local variable.
 ;; <mode>-map  : The keymap possibly associated to <mode>.
-;; <mode>-hook,<mode>-on-hook,<mode>-off-hook and <mode>-mode:
-;;       see `easy-mmode-define-minor-mode' documentation
+;; <mode>-hook : The hook run at the end of the toggle function.
+;;       see `define-minor-mode' documentation
 ;;
 ;; eval
-;;  (pp (macroexpand '(easy-mmode-define-minor-mode <your-mode> <doc>)))
+;;  (pp (macroexpand '(define-minor-mode <your-mode> <doc>)))
 ;; to check the result before using it.
 
 ;; The order in which minor modes are installed is important.  Keymap
@@ -51,107 +53,280 @@
 
 ;;; Code:
 
-(defmacro easy-mmode-define-toggle (mode &optional doc &rest body)
-  "Define a one arg toggle mode MODE function and associated hooks.
-MODE is the so defined function that toggles the mode.
-optional DOC is its associated documentation.
-BODY is executed after the toggling and before running the hooks.
-
-Hooks are checked for run, each time MODE-mode is called.
-They run under the followings conditions:
-MODE-hook: if the mode is toggled.
-MODE-on-hook: if the mode is on.
-MODE-off-hook: if the mode is off.
-
-When the mode is effectively toggled, two hooks may run.
-If so MODE-hook is guaranteed to be the first."
-  (let* ((mode-name (symbol-name mode))
-	 (hook (intern (concat mode-name "-hook")))
-	 (hook-on (intern (concat mode-name "-on-hook")))
-	 (hook-off (intern (concat mode-name "-off-hook")))
-	 (toggle-doc (or doc
-			 (format "With no argument, toggle %s.
-With universal prefix ARG turn mode on.
-With zero or negative ARG turn mode off.
-\\{%s}" mode-name (concat mode-name "-map")))))
-    `(progn
-       (defcustom ,hook  nil
-	 ,(format "Hook called when `%s' is toggled" mode-name)
-	 :type 'hook)
-
-       (defcustom ,hook-on  nil
-	 ,(format "Hook called when `%s' is turned on" mode-name)
-	 :type 'hook)
-
-       (defcustom ,hook-off nil
-	 ,(format "Hook called when `%s' is turned off" mode-name)
-	 :type 'hook)
-
-       (defun ,mode (&optional arg)
-	 ,toggle-doc
-	 (interactive "P")
-	 (let ((old-mode ,mode))
-	   (setq ,mode
-		 (if arg
-		     (> (prefix-numeric-value arg) 0)
-		   (not ,mode)))
-	   ,@body
-	   (unless (equal old-mode ,mode) (run-hooks ',hook))
-	   (run-hooks (if ,mode ',hook-on ',hook-off)))))))
+(eval-when-compile (require 'cl))
+
+(defun easy-mmode-pretty-mode-name (mode &optional lighter)
+  "Turn the symbol MODE into a string intended for the user.
+If provided LIGHTER will be used to help choose capitalization."
+  (let* ((case-fold-search t)
+	 (name (concat (replace-regexp-in-string
+			"-Minor" " minor"
+			(capitalize (replace-regexp-in-string
+				     "-mode\\'" "" (symbol-name mode))))
+		       " mode")))
+    (if (not (stringp lighter)) name
+      (setq lighter (replace-regexp-in-string "\\`\\s-+\\|\\-s+\\'" "" lighter))
+      (replace-regexp-in-string lighter lighter name t t))))
 
 ;;;###autoload
 (defalias 'easy-mmode-define-minor-mode 'define-minor-mode)
 ;;;###autoload
 (defmacro define-minor-mode (mode doc &optional init-value lighter keymap &rest body)
   "Define a new minor mode MODE.
-This function defines the associated control variable, keymap,
-toggle command, and hooks (see `easy-mmode-define-toggle').
+This function defines the associated control variable MODE, keymap MODE-map,
+toggle command MODE, and hook MODE-hook.
 
 DOC is the documentation for the mode toggle command.
 Optional INIT-VALUE is the initial value of the mode's variable.
-Optional LIGHTER is displayed in the mode-bar when the mode is on.
+Optional LIGHTER is displayed in the modeline when the mode is on.
 Optional KEYMAP is the default (defvar) keymap bound to the mode keymap.
-If it is a list, it is passed to `easy-mmode-define-keymap'
-in order to build a valid keymap.
+  If it is a list, it is passed to `easy-mmode-define-keymap'
+  in order to build a valid keymap.  It's generally better to use
+  a separate MODE-map variable than to use this argument.
+The above three arguments can be skipped if keyword arguments are
+used (see below).
+
 BODY contains code that will be executed each time the mode is (dis)activated.
-It will be executed after any toggling but before running the hooks."
+  It will be executed after any toggling but before running the hooks.
+  Before the actual body code, you can write
+  keyword arguments (alternating keywords and values).
+  These following keyword arguments are supported (other keywords
+  will be passed to `defcustom' if the minor mode is global):
+:group GROUP	Custom group name to use in all generated `defcustom' forms.
+:global GLOBAL	If non-nil specifies that the minor mode is not meant to be
+              	buffer-local, so don't make the variable MODE buffer-local.
+		By default, the mode is buffer-local.
+:init-value VAL	Same as the INIT-VALUE argument.
+:lighter SPEC	Same as the LIGHTER argument.
+:keymap MAP	Same as the KEYMAP argument.
+:require SYM	Same as in `defcustom'.
+
+For example, you could write
+  (define-minor-mode foo-mode \"If enabled, foo on you!\"
+    :lighter \" Foo\" :require 'foo :global t :group 'hassle :version \"27.5\"
+    ...BODY CODE...)"
+  (declare (debug (&define name stringp
+			   [&optional [&not keywordp] sexp
+			    &optional [&not keywordp] sexp
+			    &optional [&not keywordp] sexp]
+			   [&rest [keywordp sexp]]
+			   def-body)))
+
+  ;; Allow skipping the first three args.
+  (cond
+   ((keywordp init-value)
+    (setq body (list* init-value lighter keymap body)
+	  init-value nil lighter nil keymap nil))
+   ((keywordp lighter)
+    (setq body (list* lighter keymap body) lighter nil keymap nil))
+   ((keywordp keymap) (push keymap body) (setq keymap nil)))
+
   (let* ((mode-name (symbol-name mode))
-	 (mode-doc (format "Non-nil if mode is enabled.
-Use the function `%s' to change this variable." mode-name))
-	 (keymap-sym (intern (concat mode-name "-map")))
-	 (keymap-doc (format "Keymap for `%s'." mode-name)))
+	 (pretty-name (easy-mmode-pretty-mode-name mode lighter))
+	 (globalp nil)
+	 (group nil)
+	 (extra-args nil)
+	 (extra-keywords nil)
+	 (require t)
+	 (hook (intern (concat mode-name "-hook")))
+	 (hook-on (intern (concat mode-name "-on-hook")))
+	 (hook-off (intern (concat mode-name "-off-hook")))
+	 keyw keymap-sym)
+
+    ;; Check keys.
+    (while (keywordp (setq keyw (car body)))
+      (setq body (cdr body))
+      (case keyw
+	(:init-value (setq init-value (pop body)))
+	(:lighter (setq lighter (pop body)))
+	(:global (setq globalp (pop body)))
+	(:extra-args (setq extra-args (pop body)))
+	(:group (setq group (nconc group (list :group (pop body)))))
+	(:require (setq require (pop body)))
+	(:keymap (setq keymap (pop body)))
+	(t (push keyw extra-keywords) (push (pop body) extra-keywords))))
+
+    (setq keymap-sym (if (and keymap (symbolp keymap)) keymap
+		       (intern (concat mode-name "-map"))))
+
+    (unless group
+      ;; We might as well provide a best-guess default group.
+      (setq group
+	    `(:group ',(or (custom-current-group)
+			   (intern (replace-regexp-in-string
+				    "-mode\\'" "" mode-name))))))
+
     `(progn
        ;; Define the variable to enable or disable the mode.
-       (defvar ,mode ,init-value ,mode-doc)
-       (make-variable-buffer-local ',mode)
+       ,(if (not globalp)
+	    `(progn
+	       (defvar ,mode ,init-value ,(format "Non-nil if %s is enabled.
+Use the command `%s' to change this variable." pretty-name mode))
+	       (make-variable-buffer-local ',mode))
+
+	  (let ((curfile (or (and (boundp 'byte-compile-current-file)
+				  byte-compile-current-file)
+			     load-file-name)))
+	    `(defcustom ,mode ,init-value
+	       ,(format "Non-nil if %s is enabled.
+See the command `%s' for a description of this minor-mode.
+Setting this variable directly does not take effect;
+use either \\[customize] or the function `%s'."
+			pretty-name mode mode)
+	       :set 'custom-set-minor-mode
+	       :initialize 'custom-initialize-default
+	       ,@group
+	       :type 'boolean
+	       ,@(cond
+		  ((not (and curfile require)) nil)
+		  ((not (eq require t)) `(:require ,require))
+		  (t `(:require
+		       ',(intern (file-name-nondirectory
+				  (file-name-sans-extension curfile))))))
+	       ,@(nreverse extra-keywords))))
+
+       ;; The actual function.
+       (defun ,mode (&optional arg ,@extra-args)
+	 ,(or doc
+	      (format (concat "Toggle %s on or off.
+Interactively, with no prefix argument, toggle the mode.
+With universal prefix ARG turn mode on.
+With zero or negative ARG turn mode off.
+\\{%s}") pretty-name keymap-sym))
+	 ;; Use `toggle' rather than (if ,mode 0 1) so that using
+	 ;; repeat-command still does the toggling correctly.
+	 (interactive (list (or current-prefix-arg 'toggle)))
+	 (setq ,mode
+	       (cond
+		((eq arg 'toggle) (not ,mode))
+		(arg (> (prefix-numeric-value arg) 0))
+		(t
+		 (if (null ,mode) t
+		   (message
+		    "Toggling %s off; better pass an explicit argument."
+		    ',mode)
+		   nil))))
+	 ,@body
+	 ;; The on/off hooks are here for backward compatibility only.
+	 (run-hooks ',hook (if ,mode ',hook-on ',hook-off))
+	 (if (called-interactively-p)
+	     (progn
+	       ,(if globalp `(customize-mark-as-set ',mode))
+	       (unless (current-message)
+		 (message ,(format "%s %%sabled" pretty-name)
+			  (if ,mode "en" "dis")))))
+	 (force-mode-line-update)
+	 ;; Return the new setting.
+	 ,mode)
+
+       ;; Autoloading an easy-mmode-define-minor-mode autoloads
+       ;; everything up-to-here.
+       :autoload-end
+
+       ;; The toggle's hook.
+       (defcustom ,hook nil
+	 ,(format "Hook run at the end of function `%s'." mode-name)
+	 ,@group
+	 :type 'hook)
 
        ;; Define the minor-mode keymap.
-       ,(when keymap
+       ,(unless (symbolp keymap)	;nil is also a symbol.
 	  `(defvar ,keymap-sym
-	     (cond ((and ,keymap (keymapp ,keymap))
-		    ,keymap)
-		   ((listp ,keymap)
-		    (easy-mmode-define-keymap ,keymap))
-		   (t (error "Invalid keymap %S" ,keymap)))
-	     ,keymap-doc))
-
-       ;; Define the toggle and the hooks.
-       (easy-mmode-define-toggle ,mode ,doc ,@body)
-
-       ;; Update the mode line.
-       (or (assq ',mode minor-mode-alist)
-	   (setq minor-mode-alist
-		 (cons (list ',mode nil) minor-mode-alist)))
-       (setcar (cdr (assq ',mode minor-mode-alist)) ,lighter)
-
-       ;; Update the minor mode map.
-       (or (assq ',mode minor-mode-map-alist)
-	   (setq minor-mode-map-alist
-		 (cons (cons ',mode nil) minor-mode-map-alist)))
-       (setcdr (assq ',mode minor-mode-map-alist)
-	       ,keymap-sym)) ))
-
+	     (let ((m ,keymap))
+	       (cond ((keymapp m) m)
+		     ((listp m) (easy-mmode-define-keymap m))
+		     (t (error "Invalid keymap %S" ,keymap))))
+	     ,(format "Keymap for `%s'." mode-name)))
+
+       (add-minor-mode ',mode ',lighter
+		       ,(if keymap keymap-sym
+			  `(if (boundp ',keymap-sym)
+			       (symbol-value ',keymap-sym))))
+
+       ;; If the mode is global, call the function according to the default.
+       ,(if globalp
+	    `(if (and load-file-name (not (equal ,init-value ,mode)))
+		 (eval-after-load load-file-name '(,mode (if ,mode 1 -1))))))))
 
+;;;
+;;; make global minor mode
+;;;
+
+;;;###autoload
+(defmacro easy-mmode-define-global-mode (global-mode mode turn-on
+						     &rest keys)
+  "Make GLOBAL-MODE out of the buffer-local minor MODE.
+TURN-ON is a function that will be called with no args in every buffer
+  and that should try to turn MODE on if applicable for that buffer.
+KEYS is a list of CL-style keyword arguments:
+:group to specify the custom group."
+  (let* ((global-mode-name (symbol-name global-mode))
+	 (pretty-name (easy-mmode-pretty-mode-name mode))
+	 (pretty-global-name (easy-mmode-pretty-mode-name global-mode))
+	 (group nil)
+	 (extra-args nil)
+	 (buffers (intern (concat global-mode-name "-buffers")))
+	 (cmmh (intern (concat global-mode-name "-cmmh"))))
+
+    ;; Check keys.
+    (while (keywordp (car keys))
+      (case (pop keys)
+	(:extra-args (setq extra-args (pop keys)))
+	(:group (setq group (nconc group (list :group (pop keys)))))
+	(t (setq keys (cdr keys)))))
+
+    (unless group
+      ;; We might as well provide a best-guess default group.
+      (setq group
+	    `(:group ',(or (custom-current-group)
+			   (intern (replace-regexp-in-string
+				    "-mode\\'" "" (symbol-name mode)))))))
+
+    `(progn
+       ;; The actual global minor-mode
+       (define-minor-mode ,global-mode
+	 ,(format "Toggle %s in every buffer.
+With prefix ARG, turn %s on if and only if ARG is positive.
+%s is actually not turned on in every buffer but only in those
+in which `%s' turns it on."
+		  pretty-name pretty-global-name pretty-name turn-on)
+	 :global t :extra-args ,extra-args ,@group
+
+	 ;; Setup hook to handle future mode changes and new buffers.
+	 (if ,global-mode
+	     (progn
+	       (add-hook 'find-file-hook ',buffers)
+	       (add-hook 'change-major-mode-hook ',cmmh))
+	   (remove-hook 'find-file-hook ',buffers)
+	   (remove-hook 'change-major-mode-hook ',cmmh))
+
+	 ;; Go through existing buffers.
+	 (dolist (buf (buffer-list))
+	   (with-current-buffer buf
+	     (if ,global-mode (,turn-on) (when ,mode (,mode -1))))))
+
+       ;; Autoloading easy-mmode-define-global-mode
+       ;; autoloads everything up-to-here.
+       :autoload-end
+
+       ;; List of buffers left to process.
+       (defvar ,buffers nil)
+
+       ;; The function that calls TURN-ON in each buffer.
+       (defun ,buffers ()
+	 (remove-hook 'post-command-hook ',buffers)
+	 (while ,buffers
+	   (let ((buf (pop ,buffers)))
+	     (when (buffer-live-p buf)
+	       (with-current-buffer buf (,turn-on))))))
+       (put ',buffers 'definition-name ',global-mode)
+
+       ;; The function that catches kill-all-local-variables.
+       (defun ,cmmh ()
+	 (add-to-list ',buffers (current-buffer))
+	 (add-hook 'post-command-hook ',buffers))
+       (put ',cmmh 'definition-name ',global-mode))))
+
 ;;;
 ;;; easy-mmode-defmap
 ;;;
@@ -168,22 +343,23 @@ Use the function `%s' to change this variable." mode-name))
 	   (easy-mmode-set-keymap-parents m parents)
 	   m))))))
 
+;;;###autoload
 (defun easy-mmode-define-keymap (bs &optional name m args)
   "Return a keymap built from bindings BS.
 BS must be a list of (KEY . BINDING) where
-KEY and BINDINGS are suited as for define-key.
-optional NAME is passed to `make-sparse-keymap'.
-optional map M can be used to modify an existing map.
-ARGS is a list of additional arguments."
-  (let (inherit dense suppress)
+KEY and BINDINGS are suitable for `define-key'.
+Optional NAME is passed to `make-sparse-keymap'.
+Optional map M can be used to modify an existing map.
+ARGS is a list of additional keyword arguments."
+  (let (inherit dense)
     (while args
       (let ((key (pop args))
 	    (val (pop args)))
-	(cond
-	 ((eq key :dense) (setq dense val))
-	 ((eq key :inherit) (setq inherit val))
-	 ((eq key :group) )
-	 ;;((eq key :suppress) (setq suppress val))
+	(case key
+	 (:name (setq name val))
+	 (:dense (setq dense val))
+	 (:inherit (setq inherit val))
+	 (:group)
 	 (t (message "Unknown argument %s in defmap" key)))))
     (unless (keymapp m)
       (setq bs (append m bs))
@@ -207,11 +383,9 @@ ARGS is a list of additional arguments."
 
 ;;;###autoload
 (defmacro easy-mmode-defmap (m bs doc &rest args)
-  `(progn
-     (autoload 'easy-mmode-define-keymap "easy-mmode")
-     (defconst ,m
-       (easy-mmode-define-keymap ,bs nil (if (boundp ',m) ,m) ,(cons 'list args))
-       ,doc)))
+  `(defconst ,m
+     (easy-mmode-define-keymap ,bs nil (if (boundp ',m) ,m) ,(cons 'list args))
+     ,doc))
 
 
 ;;;
@@ -219,128 +393,92 @@ ARGS is a list of additional arguments."
 ;;;
 
 (defun easy-mmode-define-syntax (css args)
-  (let ((st (make-syntax-table (cadr (memq :copy args)))))
+  (let ((st (make-syntax-table (plist-get args :copy)))
+	(parent (plist-get args :inherit)))
     (dolist (cs css)
       (let ((char (car cs))
 	    (syntax (cdr cs)))
 	(if (sequencep char)
 	    (mapcar (lambda (c) (modify-syntax-entry c syntax st)) char)
 	  (modify-syntax-entry char syntax st))))
+    (if parent (set-char-table-parent
+		st (if (symbolp parent) (symbol-value parent) parent)))
     st))
 
 ;;;###autoload
 (defmacro easy-mmode-defsyntax (st css doc &rest args)
+  "Define variable ST as a syntax-table.
+CSS contains a list of syntax specifications of the form (CHAR . SYNTAX)."
   `(progn
      (autoload 'easy-mmode-define-syntax "easy-mmode")
-     (defconst ,st (easy-mmode-define-syntax ,css ,(cons 'list args)) doc)))
+     (defconst ,st (easy-mmode-define-syntax ,css ,(cons 'list args)) ,doc)))
 
 
 
-;;; A "macro-only" reimplementation of define-derived-mode.
-
-(defmacro easy-mmode-define-derived-mode (child parent name &optional docstring &rest body)
-  "Create a new mode as a variant of an existing mode.
-
-The arguments to this command are as follow:
-
-CHILD:     the name of the command for the derived mode.
-PARENT:    the name of the command for the parent mode (e.g. `text-mode').
-NAME:      a string which will appear in the status line (e.g. \"Hypertext\")
-DOCSTRING: an optional documentation string--if you do not supply one,
-           the function will attempt to invent something useful.
-BODY:      forms to execute just before running the
-           hooks for the new mode.
-
-Here is how you could define LaTeX-Thesis mode as a variant of LaTeX mode:
-
-  (define-derived-mode LaTeX-thesis-mode LaTeX-mode \"LaTeX-Thesis\")
-
-You could then make new key bindings for `LaTeX-thesis-mode-map'
-without changing regular LaTeX mode.  In this example, BODY is empty,
-and DOCSTRING is generated by default.
-
-On a more complicated level, the following command uses `sgml-mode' as
-the parent, and then sets the variable `case-fold-search' to nil:
-
-  (define-derived-mode article-mode sgml-mode \"Article\"
-    \"Major mode for editing technical articles.\"
-    (setq case-fold-search nil))
-
-Note that if the documentation string had been left out, it would have
-been generated automatically, with a reference to the keymap."
-
-  (let* ((child-name (symbol-name child))
-	 (map (intern (concat child-name "-map")))
-	 (syntax (intern (concat child-name "-syntax-table")))
-	 (abbrev (intern (concat child-name "-abbrev-table")))
-	 (hook (intern (concat child-name "-hook"))))
-	 
-    (when (and docstring (not (stringp docstring)))
-      ;; DOCSTRING is really the first command and there's no docstring
-      (push docstring body)
-      (setq docstring nil))
-
-    (unless (stringp docstring)
-      ;; Use a default docstring.
-      (setq docstring
-	    (format "Major mode derived from `%s' by `define-derived-mode'.
-Inherits all of the parent's attributes, but has its own keymap,
-abbrev table and syntax table:
-
-  `%s', `%s' and `%s'
-
-which more-or-less shadow %s's corresponding tables."
-		    parent map syntax abbrev parent)))
-
-    (unless (string-match (regexp-quote (symbol-name hook)) docstring)
-      ;; Make sure the docstring mentions the mode's hook
-      (setq docstring (format "%s
-This mode runs (additionally to any hooks his parent might have run)
-its own `%s' just before exiting."
-			      docstring hook)))
-
-    (unless (string-match "\\\\[{[]" docstring)
-      ;; And don't forget to put the mode's keymap
-      (setq docstring (concat docstring "\n\\{" (symbol-name map) "}")))
+;;;
+;;; easy-mmode-define-navigation
+;;;
 
+(defmacro easy-mmode-define-navigation (base re &optional name endfun narrowfun)
+  "Define BASE-next and BASE-prev to navigate in the buffer.
+RE determines the places the commands should move point to.
+NAME should describe the entities matched by RE.  It is used to build
+  the docstrings of the two functions.
+BASE-next also tries to make sure that the whole entry is visible by
+  searching for its end (by calling ENDFUN if provided or by looking for
+  the next entry) and recentering if necessary.
+ENDFUN should return the end position (with or without moving point).
+NARROWFUN non-nil means to check for narrowing before moving, and if
+found, do widen first and then call NARROWFUN with no args after moving."
+  (let* ((base-name (symbol-name base))
+	 (prev-sym (intern (concat base-name "-prev")))
+	 (next-sym (intern (concat base-name "-next")))
+         (check-narrow-maybe
+	  (when narrowfun
+	    '(setq was-narrowed
+		   (prog1 (or (< (- (point-max) (point-min)) (buffer-size)))
+		     (widen)))))
+         (re-narrow-maybe (when narrowfun
+                            `(when was-narrowed (,narrowfun)))))
+    (unless name (setq name base-name))
     `(progn
-       (defvar ,map (make-sparse-keymap))
-       (defvar ,syntax (make-char-table 'syntax-table nil))
-       (defvar ,abbrev (progn (define-abbrev-table ',abbrev nil) ,abbrev))
-     
-       (defun ,child ()
-	 ,docstring
+       (add-to-list 'debug-ignored-errors
+		    ,(concat "^No \\(previous\\|next\\) " (regexp-quote name)))
+       (defun ,next-sym (&optional count)
+	 ,(format "Go to the next COUNT'th %s." name)
 	 (interactive)
-					; Run the parent.
-	 (,parent)
-					; Identify special modes.
-	 (put ',child 'special (get ',parent 'special))
-					; Identify the child mode.
-	 (setq major-mode ',child)
-	 (setq mode-name ,name)
-					; Set up maps and tables.
-	 (unless (keymap-parent ,map)
-	   (set-keymap-parent ,map (current-local-map)))
-	 (let ((parent (char-table-parent ,syntax)))
-	   (unless (and parent (not (eq parent (standard-syntax-table))))
-	     (set-char-table-parent ,syntax (syntax-table))))
-	 (when local-abbrev-table
-	   (mapatoms
-	    (lambda (symbol)
-	      (or (intern-soft (symbol-name symbol) ,abbrev)
-		  (define-abbrev ,abbrev (symbol-name symbol)
-		    (symbol-value symbol) (symbol-function symbol))))
-	    local-abbrev-table))
-       
-	 (use-local-map ,map)
-	 (set-syntax-table ,syntax)
-	 (setq local-abbrev-table ,abbrev)
-					; Splice in the body (if any).
-	 ,@body
-					; Run the hooks, if any.
-	 (run-hooks ',hook)))))
+	 (unless count (setq count 1))
+	 (if (< count 0) (,prev-sym (- count))
+	   (if (looking-at ,re) (setq count (1+ count)))
+           (let (was-narrowed)
+             ,check-narrow-maybe
+             (if (not (re-search-forward ,re nil t count))
+                 (if (looking-at ,re)
+                     (goto-char (or ,(if endfun `(,endfun)) (point-max)))
+                   (error "No next %s" ,name))
+               (goto-char (match-beginning 0))
+               (when (and (eq (current-buffer) (window-buffer (selected-window)))
+                          (interactive-p))
+                 (let ((endpt (or (save-excursion
+                                    ,(if endfun `(,endfun)
+                                       `(re-search-forward ,re nil t 2)))
+                                  (point-max))))
+                   (unless (pos-visible-in-window-p endpt nil t)
+                     (recenter '(0))))))
+             ,re-narrow-maybe)))
+       (defun ,prev-sym (&optional count)
+	 ,(format "Go to the previous COUNT'th %s" (or name base-name))
+	 (interactive)
+	 (unless count (setq count 1))
+	 (if (< count 0) (,next-sym (- count))
+           (let (was-narrowed)
+             ,check-narrow-maybe
+             (unless (re-search-backward ,re nil t count)
+               (error "No previous %s" ,name))
+             ,re-narrow-maybe))))))
 
 
 (provide 'easy-mmode)
 
+;;; arch-tag: d48a5250-6961-4528-9cb0-3c9ea042a66a
 ;;; easy-mmode.el ends here