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From: "B. Pym" <Nobody447095@here-nor-there.org>
Newsgroups: comp.lang.lisp,comp.lang.scheme
Subject: Re: MAP (and variants) vs LOOP - Popular opinion observation?
Date: Sun, 8 Sep 2024 12:06:16 -0000 (UTC)
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> 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))

Gauche Scheme

(use srfi-13)  ;; string-upcase

(filter-map
  (lambda (x i)  (print i " - " x)
    (and (string? x) (string-upcase x)))
  '(foo "an" 8 "why")
  (lrange 0))

0 - foo
1 - an
2 - 8
3 - why
("AN" "WHY")