rotten news relay - comp.lang.lisp - Re: finding the min or max element of a list

Subject: Re: finding the min or max element of a list
From: B. Pym
Newsgroups: comp.lang.lisp
Organization: A noiseless patient Spider
Date: Thu, 18 Jul 2024 08:27 UTC

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From: Nobody447095@here-nor-there.org (B. Pym)
Newsgroups: comp.lang.lisp
Subject: Re: finding the min or max element of a list
Date: Thu, 18 Jul 2024 08:27:06 -0000 (UTC)
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> (defun best (lst cmp &key (key #'identity))
> (loop with rtn = (car lst)
> for x in (cdr lst)
> when (funcall cmp (funcall key x) (funcall key rtn))
> do (setq rtn x)
> finally (return rtn)))

Gauche Scheme

(define (best lst cmp :key (key identity))
(reduce
(lambda (x chosen)
(if (cmp (key x) (key chosen))
x chosen))
#f
lst))

(best '((a) (f o o b) (b a r) (2 3)) > :key length)
===>
(f o o b)

(best '(5 0 4 9) >)
===>
9

(best '() >)
===>
#f

(best '(2) >)
===>
2

Subject	Author
Re: finding the min or max element of a list	B. Pym

You are taking yourself far too seriously.

comp / comp.lang.lisp / Re: finding the min or max element of a list