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From: "B. Pym" <Nobody447095@here-nor-there.org>
Newsgroups: comp.lang.lisp
Subject: Re: walk through list and add all n'th item
Date: Wed, 14 Aug 2024 23:38:04 -0000 (UTC)
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B. Pym wrote:

> > Wow: loop macro rulez, somehow..
> > just one correction:
> > (loop for (a b c d) on (list 1 2 3 4 5 6 7 8) by #'cddddr
> >       sum a into a-sum
> >       sum b into b-sum
> >       sum c into c-sum
> >       sum d into d-sum
> >       finally (return (list a-sum b-sum c-sum d-sum)))
> > Yeah, i might consider this code as beautiful
> > olivier
> 
> Gauche Scheme
> 
> (use gauche.lazy)
> (use util.match)
> 
> (define data (lrange 1 57))
> 
> (match (lslices data 4)
>   [((a b c d) ...)
>    (map (cut fold + 0 <>)
>      (list a b c d))])
> 
> (378 392 406 420)


newLISP

(define data (sequence 1 56))

(map (curry apply +) (transpose (explode data 4)))

  ===>
(378 392 406 420)


Another way.

;; Using "apply" for "reduce".  The 3rd argument tells
;; apply how many items to process at a time.
(apply
  (fn (sums) (map + sums $args))
  (cons '(0 0 0 0) data)
  5)

  --->
(378 392 406 420)