Re: concentric loops

On 2024-09-12, B. Pym <Nobody447095@here-nor-there.org> wrote:

Peter Seibel wrote:
>

--> ( 11 12 13 21 22 23 31 32 33)
>
I know that in CL plus is replaced by +, but how can I
handle the mapcar inside the mapcan?

 
(loop for x from 10 to 30 by 10 nconcing
   (loop for y from 1 to 3 collect (+ x y)))

>
Gauche Scheme
>
(use srfi-42) ; list-ec
>
(list-ec (:range x 10 31 10) (:range y 1 4) (+ x y))
>
 ===>
(11 12 13 21 22 23 31 32 33)
>
Shorter:
>
(list-ec (: x 10 31 10) (: y 1 4) (+ x y))

TXR Lisp:

1> [maprod + (range 10 31 10) 1..4]
(11 12 13 21 22 23 31 32 33)

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