Question

在emacs中，是否可以获得派生模式的父模式列表？

我找到了derived-mode-p，但这只允许我测试模式是否来自另一个模式。

Answer 1

每个symbol has a property list和派生模式，此列表包含组件derived-mode-parent，它指示从哪个模式派生。它似乎只是一个符号。

(define-derived-mode nst-mode text-mode "Testing")
=> nst-mode

(get 'nst-mode 'derived-mode-parent)
=> text-mode

我不知道怎么会有多个父母。

以下是父母传递链的演示。

(define-derived-mode rope nil "Victim of mouse")
(define-derived-mode mouse rope "Victim of cat")
(define-derived-mode cat mouse "Victim of dog")
(define-derived-mode dog cat "Enough already")

(let ((mode 'dog) parents)
  (while mode
    (setq parents (cons mode parents)
          mode (get mode 'derived-mode-parent)))
  (reverse parents))

=> (dog cat mouse rope)

...或者，只是为了好玩，一个递归版本：

(defun derived-mode-parents (mode)
  (and mode
    (cons mode (derived-mode-parents
          (get mode 'derived-mode-parent)))))

(derived-mode-parents 'dog)
=> (dog cat mouse rope)

Emacs父模式列表

1 个答案: