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functionlispelispalias

Creating a Lisp alias with defalias or new function?

I want mylist to have the same functionality as list. In most Lisps (I'm on Emacs Lisp) I can simply write

(defalias 'mylist 'list)

But if I want to write my own I can write

(defun mylist (&rest x)
    (car (list x)))

which has the same functionality. But then I got this by experimenting. First, I had this code

(defun mylist (&rest x)
        (list x))

which produced a list in a list. I wasn't sure why, but the simple solution was to just put (list x) inside a car and call it good. But I'd like to know why I get a list inside a list when I don't use the car trick. What am I missing?

Solution

  • (defun my-list (&rest x) …

    The &rest parameter means that all remaining arguments are put into a list that is bound to this parameter. X then holds the list that you want. You're done.

    (defun my-list (&rest x)
  x)