Re: Returning no value

On 2024-07-18, B. Pym <Nobody447095@here-nor-there.org> wrote:

Another way.
>
(define (foo) (let1 x (random-integer 10) (and (< 5 x) x)))
>
(filter-map (^_ (foo)) (iota 10))
 ===>
(7 8 9 6 6 7)

This is the TXR Lisp interactive listener of TXR 295.
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Please listen carefully to the following spec, as our Lisp has changed.
1> [keep-keys-if (op < 5) 0..10 (ret (rand 10))]
(9 9 7)
2> [keep-keys-if (op < 5) 0..10 (ret (rand 10))]
(6 8 8 7)

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