Re: [External] : Re: Appending lists

[Jean Louis]

* Emanuel Berg via Users list for the GNU Emacs text editor 
<help-gnu-emacs@gnu.org> [2021-06-21 01:56]:
> But here it did again, despite `copy-sequence'!
> 
> (progn
>   (setq list-head '(1))
>   (setq list-tail '(2 3 4))
>   (setq list-tail-2 (copy-sequence list-tail))
>   (setq whole-list (append list-head list-tail-2))
>   (setcdr list-tail-2 '(3.5 4))
>   whole-list
> ) ; (1 2 3.5 4)

Not like that, you have to use `copy-sequence' on the last element
within `append' 

(progn
  (setq list-head '(1))
  (setq list-tail '(2 3 4))
  (setq whole-list (append list-head (copy-sequence list-tail)))
  (setcdr list-tail '(3.5 4))
  whole-list
) ⇒ (1 2 3 4)

-- 
Jean

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