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From: "B. Pym" <Nobody447095@here-nor-there.org>
Newsgroups: comp.lang.lisp
Subject: Re: MAP (and variants) vs LOOP - Popular opinion observation?
Date: Thu, 22 Aug 2024 06:35:48 -0000 (UTC)
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Nathan Baum wrote:

> Then suppose you later need the loop/map to collect some of the values
> under certain conditions. You might have
> 
>    (loop for x in (get-list)
>          for i from 0
>          do (format t "~A - ~A~%" i x)
>          if (test x)
>          collect (foo x))

newLISP

(let (result)
  (dolist (x '(2 9 22 25 42 49 58))
    (println (format "%d - %d" $idx x))
    (when (odd? x) (push (sqrt x) result -1)))
  result)

0 - 2
1 - 9
2 - 22
3 - 25
4 - 42
5 - 49
6 - 58
(3 5 7)