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Re: List of digits->number

Cross-posted to 2 groups.

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B. Pym wrote:

> Frank Buss wrote:
> 
> > (defun split-backward (number &optional (base 10))
> >   (loop while (< 0 number) collect
> >         (multiple-value-bind (quotient remainder) (floor number base)
> >           (setf number quotient)
> >           remainder)))
> > 
> > LOOP is ok, but I wonder if there is a more elegant contruct like REDUCE
> > for the opposite concept for building a list. Building the list should not
> > need more program code characters than reducing the list.
> 
> Testing:
> 
> * (split-backward 1984)
> 
> (4 8 9 1)
> 
> 
> Gauche Scheme
> 
> (use srfi-1) ; unfold
> 
> (unfold zero? (cut mod <> 10) (cut quotient <> 10) 1984)
>   ===>
> (4 8 9 1)

(do ((n 1984 (div n 10))
     (r () (cons (mod n 10) r)))
  ((zero? n) r))

  ===>
(1 9 8 4)

-- 
[T]he problem is that lispniks are as cultish as any other
devout group and basically fall down frothing at the mouth if
they see [heterodoxy]. --- Kenny Tilton (05 Dec 2004)

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Re: List of digits->number "B. Pym" <Nobody447095@here-nor-there.org> - 2024-09-21 13:59 +0000
  Re: List of digits->number "B. Pym" <Nobody447095@here-nor-there.org> - 2025-07-18 01:48 +0000

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