buffer-disable-undo error when no buffer given.

[bryan o'connor]

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Please write in English if possible, because the Emacs maintainers
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Please describe exactly what actions triggered the bug
and the precise symptoms of the bug:

(buffer-disable-undo)

Debugger entered--Lisp error: (wrong-type-argument stringp nil)
  get-buffer(nil)
  buffer-disable-undo()
  eval((buffer-disable-undo))
  eval-last-sexp-1(nil)
  eval-last-sexp(nil)
  call-interactively(eval-last-sexp)

simple fix:

(defun buffer-disable-undo (&optional buffer)
  "Make BUFFER stop keeping undo information.
No argument or nil as argument means do this for the current buffer."
  (interactive)
  (with-current-buffer (if buffer
                           (get-buffer buffer)
                         (current-buffer))
    (setq buffer-undo-list t
          undo-list-saved nil)))

In GNU Emacs 21.3.50.1 (powerpc-apple-darwin7.7.0)
 of 2004-12-27 on crazymonkey.local
Distributor `Apple Computers', version 10.3.7
configured using `configure '--without-x' '--prefix=/usr/local''

Important settings:
  value of $LC_ALL: nil
  value of $LC_COLLATE: nil
  value of $LC_CTYPE: nil
  value of $LC_MESSAGES: nil
  value of $LC_MONETARY: nil
  value of $LC_NUMERIC: nil
  value of $LC_TIME: nil
  value of $LANG: nil
  locale-coding-system: nil
  default-enable-multibyte-characters: t

Major mode: Emacs-Lisp

Minor modes in effect:
  show-paren-mode: t
  mouse-wheel-mode: t
  menu-bar-mode: t
  global-font-lock-mode: t
  font-lock-mode: t
  unify-8859-on-encoding-mode: t
  utf-translate-cjk-mode: t
  column-number-mode: t
  line-number-mode: t
  transient-mark-mode: t

Recent input:
) ) C-n C-n C-x C-e <escape> x s l i m e <return> C-x
b <return> C-n C-n C-p C-p C-p C-p C-a C-p C-p C-p
C-p C-p C-p C-s g e t - b u f f e r C-s C-n C-p C-s
C-s C-s C-s C-s C-a C-p C-s g e t - b u f f e r SPC
C-s C-s C-s C-s C-s C-s C-s C-a C-p C-p C-p C-p C-n
C-n C-n <down-mouse-1> <mouse-movement> <mouse-movement>
<drag-mouse-1> M-w C-h b C-n C-n C-n C-n C-s b u g
C-s C-s C-a C-g <menu-bar> <help-menu> <report-ema
cs-bug>

Recent messages:
Info-follow-nearest-node: Point neither on reference nor in menu item 
description
#<buffer *scratch*>
buffer-disable-undo
Polling "/tmp/slime.15731".. (Abort with `M-x slime-abort-connection'.) 
[4 times]
Connecting to Swank on port 64859..
Mark saved where search started [3 times]
Describe-Bindings...
Mark saved where search started
Quit
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