flet 有效，但消息已过时； cl-flet 不起作用

Question

我正在尝试暂时关闭在别处定义的函数中的yes-or-no-p，然后将其恢复到原来的样子。使用 flet 有效，但会创建一个 *compile-log* 缓冲区，告诉我它已过时并改用 cl-flet。但是，cl-flet 似乎不适用于defadvice 的这种尝试——即，什么都没有发生，yes-or-no-p 仍然有效。关于如何避免错误消息并使这项工作也能发挥作用的任何想法？

(defun function-without-confirmation ()

(defadvice elmo-dop-queue-flush (around stfu activate)
      (flet ((yes-or-no-p (&rest args) t)
             (y-or-n-p (&rest args) t))
        ad-do-it))

. . . .


(ad-unadvise 'elmo-dop-queue-flush)

)

---

我不能把答案归功于这个答案，因为 wvxvw 已经解决了这个问题，所以我将把相关的修复放在原始问题的下面。新的宏被称为lawlist-flet instad of flet，过时的行已被注释掉：

(defmacro lawlist-flet (bindings &rest body)
  "Make temporary overriding function definitions.
This is an analogue of a dynamically scoped `let' that operates on the function
cell of FUNCs rather than their value cell.
If you want the Common-Lisp style of `flet', you should use `cl-flet'.
The FORMs are evaluated with the specified function definitions in place,
then the definitions are undone (the FUNCs go back to their previous
definitions, or lack thereof).

\(fn ((FUNC ARGLIST BODY...) ...) FORM...)"
  (declare (indent 1) (debug cl-flet)
;;           (obsolete "use either `cl-flet' or `cl-letf'."  "24.3")
                )
  `(letf ,(mapcar
           (lambda (x)
             (if (or (and (fboundp (car x))
                          (eq (car-safe (symbol-function (car x))) 'macro))
                     (cdr (assq (car x) macroexpand-all-environment)))
                 (error "Use `labels', not `flet', to rebind macro names"))
             (let ((func `(cl-function
                           (lambda ,(cadr x)
                             (cl-block ,(car x) ,@(cddr x))))))
               (when (cl--compiling-file)
                 ;; Bug#411.  It would be nice to fix this.
                 (and (get (car x) 'byte-compile)
                      (error "Byte-compiling a redefinition of `%s' \
will not work - use `labels' instead" (symbol-name (car x))))
                 ;; FIXME This affects the rest of the file, when it
                 ;; should be restricted to the flet body.
                 (and (boundp 'byte-compile-function-environment)
                      (push (cons (car x) (eval func))
                            byte-compile-function-environment)))
               (list `(symbol-function ',(car x)) func)))
           bindings)
     ,@body))

而且，这里是修改后的函数，它消除了与 flet 已过时有关的错误消息。

(defun function-without-confirmation ()

(defadvice elmo-dop-queue-flush (around stfu activate)
      (lawlist-flet ((yes-or-no-p (&rest args) t)
             (y-or-n-p (&rest args) t))
        ad-do-it))

. . . .


(ad-unadvise 'elmo-dop-queue-flush)

Answer 1

我建议你这样做：

(defvar stfu-inhibit-yonp nil)
(defadvice yes-or-no-p (around stfu activate)
  (if stfu-inhibit-yonp (setq ad-return t) ad-do-it))
(defadvice y-or-n-p (around stfu activate)
  (if stfu-inhibit-yonp (setq ad-return t) ad-do-it))

(defadvice elmo-dop-queue-flush (around stfu activate)
  (let ((stfu-inhibit-yonp t))
    ad-do-it))

与 CL 的 flet 相反，这将清楚地表明（例如在 C-h f yes-or-no-p 中）是或否 p 正在发生某些事情。