[plt-scheme] Re: Novice needs help writing function

Thanks for all the input everyone.

I took N's advice, revisited the problem by stepping through the
design recipe, and came up with the following core and auxiliary
functions which cheat a bit....

(define (apply-n1 face count)
   (cond
      [(zero? count) (draw-losh face)]
      [else (apply-n3(move-picture 1 face)(sub1 count))]))

(define (apply-n count)
  (apply-n3 FACE count))

Does this solution satisfy the pedagogical function of the problem?

Also, cheers to M. for a wonderful book!  For awhile I've had an
interest in computer programming, but career obligations have
relegated it to a hobby.  For someone like me, who has never taken a
CS course and is not very good at math, the text is a godsend!

Having come across the concept of recursion in general interest texts
like Godel Escher Bach and Godel's Proof, thanks to HTDP, I finally
feel as though I've gained some basic understanding of how it works.
I'm not sure if this is the appropriate forum, but I was wondering if
anyone could recommend a good introductory text on recursion
comprehensible to a non-specialist like myself.  I think it's a
fascinating topic, and I'd love to learn more about it.











On Dec 29, 7:14 am, Matthias Felleisen <matth... at ccs.neu.edu> wrote:
> In this particular case, the problem is on my side. Working
> with draw.ss just doesn't fit with the natural development of
> the design recipe. I should have taken this symptom more seriously
> when I wrote this extended exercise. -- Matthias
>
> On Dec 29, 2007, at 8:42 AM, Noel Welsh wrote:
>
> > The design recipes are a (if not the) core part of HtDP.  HtDP is the
> > only book I know that takes designing programs from a dark and
> > mysterious art to a systematic process anyone can apply.  This is a
> > really really powerful idea.  So, if you haven't worked through the
> > design recipe, do so.  If you have, then you might say what
> > difficulties you are having applying the recipe.
>
> > N.
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