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From: Kaz Kylheku <643-408-1753@kylheku.com>
Newsgroups: comp.lang.lisp
Subject: Re: CAR/CDR vs FIRST/REST
Date: Tue, 2 Jul 2024 22:58:00 -0000 (UTC)
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On 2024-07-02, B. Pym <No_spamming@noWhere_7073.org> wrote:
> Barry Margolin wrote:
>
>> >       (mapcan #'(lambda (x) (and (numberp x) (list x))) list)
>> 
>> >       (loop for x in list
>> >               when (numberp x) collect x)
>> 
>> I agree with this example.  Once I learned LOOP I never used the
>> above idiom again.
>
>
> (filter number? '(a b c 1 2 3))
> ===>
> (1 2 3)

In Common Lisp, filter has a funny name: remove-if-not.

  (remove-if-not #'numberp '(a b c 1 2 3))
  -->
  (1 2 3)

Likely because of the funny name, the function is marked deprecated,
which is silly.

-- 
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