[Emacs-diffs] Changes to emacs/lisp/simple.el

[Luc Teirlinck]

Index: emacs/lisp/simple.el
diff -c emacs/lisp/simple.el:1.687 emacs/lisp/simple.el:1.688
*** emacs/lisp/simple.el:1.687  Sat Jan 29 17:24:41 2005
--- emacs/lisp/simple.el        Sun Jan 30 00:32:39 2005
***************
*** 1525,1557 ****
             '(0 . 0)))
      '(0 . 0)))
  
  (defvar undo-extra-outer-limit nil
    "If non-nil, an extra level of size that's ok in an undo item.
  We don't ask the user about truncating the undo list until the
! current item gets bigger than this amount.")
  (make-variable-buffer-local 'undo-extra-outer-limit)
  
! ;; When the first undo batch in an undo list is longer than undo-outer-limit,
! ;; this function gets called to ask the user what to do.
! ;; Garbage collection is inhibited around the call,
! ;; so it had better not do a lot of consing.
  (setq undo-outer-limit-function 'undo-outer-limit-truncate)
  (defun undo-outer-limit-truncate (size)
!   (when (or (null undo-extra-outer-limit)
!           (> size undo-extra-outer-limit))
!     ;; Don't ask the question again unless it gets even bigger.
!     ;; This applies, in particular, if the user quits from the question.
!     ;; Such a quit quits out of GC, but something else will call GC
!     ;; again momentarily.  It will call this function again,
!     ;; but we don't want to ask the question again.
!     (setq undo-extra-outer-limit (+ size 50000))
!     (if (let (use-dialog-box)
!         (yes-or-no-p (format "Buffer %s undo info is %d bytes long; discard 
it? "
!                              (buffer-name) size)))
!       (progn (setq buffer-undo-list nil)
!              (setq undo-extra-outer-limit nil)
!              t)
!       nil)))
  
  (defvar shell-command-history nil
    "History list for some commands that read shell commands.")
--- 1525,1600 ----
             '(0 . 0)))
      '(0 . 0)))
  
+ (defcustom undo-ask-before-discard t
+   "If non-nil ask about discarding undo info for the current command.
+ Normally, Emacs discards the undo info for the current command if
+ it exceeds `undo-outer-limit'.  But if you set this option
+ non-nil, it asks in the echo area whether to discard the info.
+ If you answer no, there a slight risk that Emacs might crash, so
+ only do it if you really want to undo the command.
+ 
+ This option is mainly intended for debugging.  You have to be
+ careful if you use it for other purposes.  Garbage collection is
+ inhibited while the question is asked, meaning that Emacs might
+ leak memory.  So you should make sure that you do not wait
+ excessively long before answering the question."
+   :type 'boolean
+   :group 'undo
+   :version "21.4")
+ 
  (defvar undo-extra-outer-limit nil
    "If non-nil, an extra level of size that's ok in an undo item.
  We don't ask the user about truncating the undo list until the
! current item gets bigger than this amount.
! 
! This variable only matters if `undo-ask-before-discard' is non-nil.")
  (make-variable-buffer-local 'undo-extra-outer-limit)
  
! ;; When the first undo batch in an undo list is longer than
! ;; undo-outer-limit, this function gets called to warn the user that
! ;; the undo info for the current command was discarded.  Garbage
! ;; collection is inhibited around the call, so it had better not do a
! ;; lot of consing.
  (setq undo-outer-limit-function 'undo-outer-limit-truncate)
  (defun undo-outer-limit-truncate (size)
!   (if undo-ask-before-discard
!       (when (or (null undo-extra-outer-limit)
!               (> size undo-extra-outer-limit))
!       ;; Don't ask the question again unless it gets even bigger.
!       ;; This applies, in particular, if the user quits from the question.
!       ;; Such a quit quits out of GC, but something else will call GC
!       ;; again momentarily.  It will call this function again,
!       ;; but we don't want to ask the question again.
!       (setq undo-extra-outer-limit (+ size 50000))
!       (if (let (use-dialog-box track-mouse executing-kbd-macro )
!             (yes-or-no-p (format "Buffer %s undo info is %d bytes long; 
discard it? "
!                                  (buffer-name) size)))
!           (progn (setq buffer-undo-list nil)
!                  (setq undo-extra-outer-limit nil)
!                  t)
!         nil))
!     (display-warning '(undo discard-info)
!                    (concat
!                     (format "Buffer %s undo info was %d bytes long.\n"
!                             (buffer-name) size)
!                     "The undo info was discarded because it exceeded \
! `undo-outer-limit'.
! 
! This is normal if you executed a command that made a huge change
! to the buffer.  In that case, to prevent similar problems in the
! future, set `undo-outer-limit' to a value that is large enough to
! cover the maximum size of normal changes you expect a single
! command to make, but not so large that it might exceed the
! maximum memory allotted to Emacs.
! 
! If you did not execute any such command, the situation is
! probably due to a bug and you should report it.
! 
! You can disable the popping up of this buffer by adding the entry
! \(undo discard-info) to the user option `warning-suppress-types'.\n")
!                    :warning)
!     (setq buffer-undo-list nil)
!     t))
  
  (defvar shell-command-history nil
    "History list for some commands that read shell commands.")