就是按 C-h k ( 看帮助文档指示它对应的是哪个 command ,我这是 self-insert-command ,它有一些提示:

( runs the command self-insert-command (found in global-map), which is
an interactive built-in function in ‘C source code’.

It is bound to many ordinary text characters.

(self-insert-command N &optional C)

  Probably introduced at or before Emacs version 22.1.

Insert the character you type.
Whichever character C you type to run this command is inserted.
The numeric prefix argument N says how many times to repeat the insertion.
Before insertion, ‘expand-abbrev’ is executed if the inserted character does
not have word syntax and the previous character in the buffer does.
After insertion, ‘internal-auto-fill’ is called if
‘auto-fill-function’ is non-nil and if the ‘auto-fill-chars’ table has
a non-nil value for the inserted character.  At the end, it runs


(when (maybe-require-package 'aggressive-indent)
  (add-to-list 'sanityinc/lispy-modes-hook 'aggressive-indent-mode))