Question

我正在尝试创建一个能够从emacs'*Buffer List*缓冲区恢复缓冲区的函数。据我所知，文档中没有办法快速执行此操作（以buff-menu.el内置的save / mark / visit函数的方式）。所以我正在写一些elisp。这是我目前的尝试：

(defun frobnitz ()
  "Call in buffer list to revert buffer at point to file."
  (interactive)
  (let ((buf (buffer-menu-buffer t)))
    (if (y-or-n-p (concat "Revert " (buffer-name (buf)) " ?"))
    (with-current-buffer buf
      (let (())
        (revert-buffer t t t)
        (message
          (concat "Reverted " (buffer-name (buf)) "to last saved state."))
        )))))

不幸的是，上述修改似乎不起作用，我无法弄清楚原因。如果我评估上述内容，请切换到*Buffer List*缓冲区，然后调用 M- :( frobnitz），然后出现以下错误。

Debugger entered--Lisp error: (void-function buffer-menu-buffer)
  (buffer-menu-buffer t)
  (let ((buf (buffer-menu-buffer t))) (if (y-or-n-p (concat "Revert " (buffer-name (buf)) " ?")) (with-current-buffer buf (let (nil) (revert-buffer t t t) (message (concat "Reverted " (buffer-name (buf)) "to last saved state."))))))
  frobnitz()
  eval((frobnitz) nil)
  eval-expression((frobnitz) nil)
  call-interactively(eval-expression nil nil)

似乎这告诉我没有函数buffer-menu-buffer - 但这似乎也不太可能，因为buffer-menu-buffer是使缓冲区菜单工作的一个非常重要的功能！出于类似的原因，我非常警惕自己弄错buffer-menu-buffer - 我不想打破缓冲区菜单。

请记住，答案可能是“调用你忽略的这个函数”，我怎样才能完成它的目的，即直接从缓冲区菜单恢复缓冲区？

更新：正如回答者Sean所指出的那样，我正在努力工作的函数的正确名称是Buffer-menu-buffer，首字母为B.修复了这个问题，我来了另一个：

  (let (nil) (revert-buffer t t t) (message (concat "Reverted " buf-name "to last saved state.")))
  (save-current-buffer (set-buffer buf) (let (nil) (revert-buffer t t t) (message (concat "Reverted " buf-name "to last saved state."))))
  (with-current-buffer buf (let (nil) (revert-buffer t t t) (message (concat "Reverted " buf-name "to last saved state."))))
  (if (y-or-n-p (concat "Revert " buf-name " ?")) (with-current-buffer buf (let (nil) (revert-buffer t t t) (message (concat "Reverted " buf-name "to last saved state.")))))
  (let ((buf (Buffer-menu-buffer t)) (buf-name (concat "" (buffer-name (Buffer-menu-buffer t))))) (if (y-or-n-p (concat "Revert " buf-name " ?")) (with-current-buffer buf (let (nil) (revert-buffer t t t) (message (concat "Reverted " buf-name "to last saved state."))))))
  frobnitz()
  eval((frobnitz) nil)
  eval-expression((frobnitz) nil)
  call-interactively(eval-expression nil nil)

我的猜测是with-current-buffer尝试保存当前缓冲区，这是*Buffer List*上的禁忌。所以现在我正在寻找替代方案 - 可能只需切换，恢复并调用(buffer-list)切换回来。

更新2：

对于未来的读者：工作函数和在buffer-menu-mode中调用它的单键绑定：

;; Enhance the buffer menu's capabilities.
(defun revert-buffer-from-buffer-list ()
  "Call in buffer list to revert buffer at point to file.

Bind this to a key in `buffer-menu-mode' to use it there - not productive in
other modes because it depends on the `Buffer-menu-buffer' function. Undefined
behavior if you invoke it on a buffer not associated with a file: that's why it
has a confirmation gate. Buffers not associated with files get to play by their
own rules when it comes to `revert-buffer' (which see)."
  (interactive)
  (let (
        (buf (Buffer-menu-buffer t))
        (buf-name (concat "" (buffer-name(Buffer-menu-buffer t))))
        )
    (if (y-or-n-p (concat "Revert " buf-name " ?"))
        (with-current-buffer buf
          (let ()
            (revert-buffer t t t)
            (message (concat "Reverted " buf-name " to last saved state."))
            )))))
(add-hook 'Buffer-menu-mode-hook
          (lambda ()
            (define-key Buffer-menu-mode-map (kbd "R") revert-buffer-from-buffer-list)
            ))

另外要谨慎提醒：add-hook不是幂等的，所以如果你向foo-mode-hook添加你不打算或不工作的东西，你就有可能破坏{{1}直到你zorch foo-mode或修剪破碎的元素。问我怎么知道！

Answer 1

我的Emacs有一个功能Buffer-menu-buffer，但没有buffer-menu-buffer。我想这就是绊倒你。

编辑：

我发现你的代码还有两个问题，之后我可以用缓冲区菜单恢复缓冲区。

我必须在两个地方将(buf)更改为buf。 buf是一个变量，而不是要调用的函数。
(let (()) ...)构造导致错误。消除它，或将其更改为(let () ...)（虽然我不知道你为什么要这样做）。

如何在emacs的缓冲区列表中恢复缓冲区？

1 个答案: