[racket] Advice: simulating stateful API in functional setting

On Jul 16, 2011, at 10:16 AM, Stephen Bloch wrote:

> I'm looking at our competition in the marketplace of ideas, and I want to beat (or at least match) them at their own game.
> 
> Who's with me?

Since these people have no scruples -- don't even understand that they dont have any -- go for the imperative version. 

> Every workshop on Python or Processing in education includes an example ("which students can do on the first day," although largely by copying and tinkering rather than deep understanding) 

We can do an animation on the first day. Our students actually understand what they do and why it works. And the idea is 100% algebra. So why cave? Why not attack them?