[plt-scheme] Code review: garden fence encryption

From: Marek Kubica (marek at xivilization.net)
Date: Mon Mar 16 08:39:00 EDT 2009

Hi David,

Thanks for your implementation!

On Sun, 15 Mar 2009 16:57:10 -0400
David Van Horn <dvanhorn at ccs.neu.edu> wrote:

> My solution is shorter than yours and exploits a symmetry in
> encrypting and decrypting that yours missed.

Yes, the decryption was tacked on later and by then I understood the
problem a litte bit better. I'll try to make my encryption and
decryption more symmetric.

Much of the uglyness in my code is caused by build-phases &
merge-phases which you solved way easier in `fence'. I'll definitely
take a look at it, since most time writing my solution was spent
writing code to create fences.

And the htdp/testing part is very nice, an easy to use library for
testing expected results. I didn't know that PLT ships something like


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