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diff --git a/lisp/erc/erc-ring.el b/lisp/erc/erc-ring.el
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+;; erc-ring.el -- Command history handling for erc using ring.el
+
+;; Copyright (C) 2001, 2002, 2003, 2004 Free Software Foundation, Inc.
+
+;; Author: Alex Schroeder <alex@gnu.org>
+;; Keywords: comm
+;; URL: http://www.emacswiki.org/cgi-bin/wiki.pl?ErcHistory
+
+;; This file is part of GNU Emacs.
+
+;; GNU Emacs is free software; you can redistribute it and/or modify
+;; it under the terms of the GNU General Public License as published by
+;; the Free Software Foundation; either version 2, or (at your option)
+;; any later version.
+
+;; GNU Emacs is distributed in the hope that it will be useful,
+;; but WITHOUT ANY WARRANTY; without even the implied warranty of
+;; MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+;; GNU General Public License for more details.
+
+;; You should have received a copy of the GNU General Public License
+;; along with GNU Emacs; see the file COPYING.  If not, write to the
+;; Free Software Foundation, Inc., 51 Franklin Street, Fifth Floor,
+;; Boston, MA 02110-1301, USA.
+
+;;; Commentary:
+
+;; This file implements an input ring -- a history of the stuff you
+;; wrote.  To activate:
+;;
+;; (require 'erc-auto) or (require 'erc-ring)
+;; (erc-ring-mode 1)
+;;
+;; Use M-n and M-p to navigate the ring
+
+;;; Code:
+
+(require 'erc)
+(require 'comint)
+(require 'ring)
+
+;;;###autoload (autoload 'erc-ring-mode "erc-ring" nil t)
+(define-erc-module ring nil
+  "Stores input in a ring so that previous commands and messages can
+be recalled using M-p and M-n."
+  ((add-hook 'erc-send-pre-hook 'erc-add-to-input-ring)
+   (define-key erc-mode-map "\M-p" 'erc-previous-command)
+   (define-key erc-mode-map "\M-n" 'erc-next-command))
+  ((remove-hook 'erc-send-pre-hook 'erc-add-to-input-ring)
+   (define-key erc-mode-map "\M-p" 'undefined)
+   (define-key erc-mode-map "\M-n" 'undefined)))
+
+(defvar erc-input-ring nil "Input ring for erc.")
+(make-variable-buffer-local 'erc-input-ring)
+
+(defvar erc-input-ring-index nil
+  "Position in the input ring for erc.
+If nil, the input line is blank and the user is conceptually 'after'
+the most recently added item in the ring. If an integer, the input
+line is non-blank and displays the item from the ring indexed by this
+variable.")
+(make-variable-buffer-local 'erc-input-ring-index)
+
+(defun erc-input-ring-setup ()
+  "Do the setup required so that we can use comint style input rings.
+Call this function when setting up the mode."
+  (setq erc-input-ring (make-ring comint-input-ring-size))
+  (setq erc-input-ring-index nil))
+
+(defun erc-add-to-input-ring (s)
+  "Add string S to the input ring and reset history position."
+  (unless erc-input-ring (erc-input-ring-setup))
+  (ring-insert erc-input-ring s)
+  (setq erc-input-ring-index nil))
+
+(defun erc-clear-input-ring ()
+  "Remove all entries from the input ring, then call garbage-collect.
+You might use this for security purposes if you have typed a command
+containing a password."
+  (interactive)
+  (setq erc-input-ring (make-ring comint-input-ring-size)
+        erc-input-ring-index nil)
+  (garbage-collect)
+  (message "ERC input ring cleared."))
+
+(defun erc-previous-command ()
+  "Replace current command with the previous one from the history."
+  (interactive)
+  (unless erc-input-ring (erc-input-ring-setup))
+  ;; if the ring isn't empty
+  (when (> (ring-length erc-input-ring) 0)
+    (if (and erc-input-ring-index
+             (= (ring-length erc-input-ring) (1+ erc-input-ring-index)))
+        (progn
+          (erc-replace-current-command "")
+          (setq erc-input-ring-index nil))
+
+      ;; If we are not viewing old input and there's text in the input
+      ;; area, push it on the history ring before moving back through
+      ;; the input history, so it will be there when we return to the
+      ;; front.
+      (if (null erc-input-ring-index)
+          (when (> (point-max) erc-input-marker)
+            (erc-add-to-input-ring (buffer-substring erc-input-marker
+                                                     (point-max)))
+            (setq erc-input-ring-index 0)))
+
+      (setq erc-input-ring-index (if erc-input-ring-index
+                                     (ring-plus1 erc-input-ring-index
+                                                 (ring-length erc-input-ring))
+                                   0))
+      (erc-replace-current-command (ring-ref erc-input-ring
+                                             erc-input-ring-index)))))
+
+(defun erc-next-command ()
+  "Replace current command with the next one from the history."
+  (interactive)
+  (unless erc-input-ring (erc-input-ring-setup))
+  ;; if the ring isn't empty
+  (when (> (ring-length erc-input-ring) 0)
+    (if (and erc-input-ring-index
+             (= 0 erc-input-ring-index))
+        (progn
+          (erc-replace-current-command "")
+          (setq erc-input-ring-index nil))
+      (setq erc-input-ring-index (ring-minus1 (or erc-input-ring-index 0)
+                                              (ring-length erc-input-ring)))
+      (erc-replace-current-command (ring-ref erc-input-ring
+      erc-input-ring-index)))))
+
+
+(defun erc-replace-current-command (s)
+  "Replace current command with string S."
+  ;; delete line
+  (let ((inhibit-read-only t))
+    (delete-region
+     (progn (goto-char erc-insert-marker) (erc-bol))
+     (goto-char (point-max)))
+    (insert s)))
+
+(provide 'erc-ring)
+
+;;; erc-ring.el ends here
+;; Local Variables:
+;; indent-tabs-mode: nil
+;; End:
+
+;; arch-tag: b77924a8-a80e-489d-84cd-b351761ea5c8