@ 字符在 Emacs Lisp 中的作用是什么?

What is the role of the @ character in Emacs Lisp?

例如在这个宏定义中使用:

(defmacro with-eval-after-load-feature (feature &rest body)
  (declare (indent 1) (debug t))
  (let* ((feature (if (and (listp feature) (eq (car-safe feature) 'quote))
                      (cdr feature) feature))
         (fs (if (listp feature) feature (list feature)))
         (form (or (and (eval '(eval-when (compile)
                                 (with-eval-after-load-feature-preload fs)))
                        'with-no-warnings)
                   'progn)))
    `(,form ,@(with-eval-after-load-feature-transform fs body))))

this file.

用于反引号表达式中的拼接。参见 C-h i g (elisp) Backquote RET。例如:

elisp> `(1 2 ,(list 3 4))  ; no splicing => nested list
(1 2
   (3 4))

elisp> `(1 2 ,@(list 3 4)) ; splicing => flat list
(1 2 3 4)

询问 Emacs 始终是一个明智的方法:

  • C-hig (elisp) RET
  • @ RET

这会向您显示 @ 的所有 elisp 手册索引条目(其中一个是您实际要查找的 ,@)。