如何恢复emacs缓冲区列表中的缓冲区？

Question

我试图创建一个函数，它将从emacs的*Buffer List*缓冲区中恢复缓冲区。据我可以从文档中看出，无法快速执行此操作（以内置于buff-menu.el的保存/标记/访问功能的方式）。所以我正在写一些elisp。这是我当前的尝试：

(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defun定义似乎并没有工作，我无法弄清楚为什么。如果我评估上述内容，请切换到*Buffer List*缓冲区，并调用M- :(frobnitz），然后错误地输出以下内容。

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) 

好像是在告诉我，有没有功能buffer-menu-buffer - 但似乎也不太可能无偿，因为buffer-menu-buffer是在得到缓冲菜单的工作一个相当核心功能！由于类似的原因，我对自己搞了buffer-menu-buffer非常警惕 - 我不想打破缓冲菜单。

考虑到答案可能是“调用你忽略的这个函数”，我该如何获得这个defun来完成其直接从缓冲区菜单中恢复缓冲区的目的？

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更新：作为回答者肖恩指出，我有一个艰难的时间与功能的正确名称是Buffer-menu-buffer大写初始B.有固定的这个问题，我遇到了另一个问题：

(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试图保存当前的缓冲区，这是*Buffer List*的禁止。所以现在我正在寻找替代品 - 也许只是切换，恢复，并调用(buffer-list)切换回来。

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更新2：

对于未来的读者：工作功能和单键绑定来调用它buffer-menu-mode：

;; 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) 
      )) 

而且在劝勉告诫：add-hook是不幂等，所以如果你添加的东西foo-mode-hook，你不打算或不工作，你冒险破坏foo-mode，直到你zorch foo-mode-hook或修剪掉它的破碎元素。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。我想那是什么让你感到沮丧。

编辑：

我发现了两个更多的问题与您的代码，在这之后我能够从它的缓冲菜单恢复缓冲区。

• 我不得不在两个地方将(buf)更改为buf。 buf是一个变量，不是要调用的函数。
• 构造(let (()) ...)会导致错误。要么消除它，要么将其更改为(let() ...)（尽管我不知道你为什么要这么做）。