Emacs:保存文件时如何设置文件大小警告显着减少？

Question

我刚刚在文本文件中丢失了大部分内容,当我使用emacs时,有一个错误,但我忽略了错误消息,并强制保存文件.几个小时后,我发现我新保存的文件只剩下几个字节了!我在文件中的大部分笔记都已消失.

我希望在emacs中保存文件时,我已经设置了大大改变文件大小的警告.我以前在emacs之前看过这样的消息,但我不知道我现在怎么设置它？请与我分享指向解决方案的任何指针.最糟糕的是,应该可以在钩子中添加一些检查来保存文件以实现它.

提前致谢!

于申

Answer 1

根据您想要的警告类型,这可以解决您的问题.当前的增量为8M,显然您可以根据需要自定义.如果您想要一个更具侵入性的警告,您可以取消对该呼叫的注释'y-or-n-p,并删除该消息.

(defvar check-buffer-size-delta (* 8 1024 1024)
  "Delta in size over which the user will be warned when saving.")
(defun check-buffer-size-on-save ()
  "Warn user if buffer has changed by more than CHECK-BUFFER-SIZE-DELTA since last save"
  (let ((delta (abs (- (buffer-size) buffer-saved-size))))
    (when (> delta check-buffer-size-delta)
      (beep)
      ;; (y-or-n-p "WARNING: Buffer has changed by %d bytes since last save.  Do you know what you're doing? "
      (message "WARNING: Buffer has changed by %d bytes since last save." delta))))

(add-hook 'before-save-hook 'check-buffer-size-on-save)