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

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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 ?

--- SoupGate-Win32 v1.05
* Origin: fsxNet Usenet Gateway (21:1/5)

On 7/23/2024 12:27 PM, HenHanna wrote:

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 ?

is there a convention for printing a Colon ( : ) before something?

--- SoupGate-Win32 v1.05
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