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From: "B. Pym" <Nobody447095@here-nor-there.org>
Newsgroups: comp.lang.lisp,comp.lang.scheme
Subject: Re: chain of transformations
Date: Tue, 17 Sep 2024 11:07:52 -0000 (UTC)
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Kaz Kylheku wrote:

> (defun tree-find (needle haystack &key (test #'eql))
>   (dolist (item haystack)
>     (if (funcall test needle item)
>       (return item)
>       (when (consp item)
>         (let ((find (tree-find needle item :test test)))
>           (when find
>             (return find)))))))

Gauche Scheme:

(define (tree-find needle haystack :optional (test equal?))
  (any
    (lambda (item)
      (if (test needle item)
        item 
        (and (pair? item) (tree-find needle item test))))
    haystack))