Re: Descending

Liste des GroupesRevenir à cl lisp 
Sujet : Re: Descending
De : HenHanna (at) *nospam* devnull.tb (HenHanna)
Groupes : comp.lang.lisp
Date : 23. Jul 2024, 21:27:39
Autres entêtes
Organisation : A noiseless patient Spider
Message-ID : <v7p07b$1b339$4@dont-email.me>
References : 1
User-Agent : Mozilla Thunderbird
On 6/7/2024 3:57 AM, B. Pym wrote:
 Ken Tilton wrote:
 
I am having trouble coding a list traversal segment.
         eg list:
>
(a (b) (c (e (h i)) (f (j))) (d (g)))
>
I want to traverse this list in "preorder" and get the following
output:
>
                 a b c e h i f j d g
>
anyone have a code segment to this?
>
thanks....
>
Chris.

>
Will this work?:
>
(defun dump (list-or-atom)
    (if (listp list-or-atom)
       (dolist (loa list-or-atom)
           (dump loa))
       (format t "~s " list-or-atom)))
 Gauche Scheme:
 (define (dump list-or-atom)
   (cond ((null? list-or-atom) )
         ((list? list-or-atom)
           (begin
             (dump (car list-or-atom))
             (dump (cdr list-or-atom))))
         (#t (format #t ":~s " list-or-atom))))
 (dump '(a (b) (c (e (h i)) (f (j))) (d (g))))
   ===>
          :a :b :c :e :h :i :f :j :d :g          #t
 
(i've added some spaces)
the good ol'  Flatten ?

Date Sujet#  Auteur
7 Jun 24 * Descending5B. Pym
23 Jul 24 `* Re: Descending4HenHanna
12 Aug 24  +- Re: Descending1steve g
12 Aug 24  `* Re: Descending2HenHanna
12 Aug 24   `- Re: Descending1Jeff Barnett

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