[plt-scheme] Scheme grade calculator

From: Stephen Bloch (sbloch at adelphi.edu)
Date: Tue Apr 27 09:08:01 EDT 2010

On Apr 27, 2010, at 1:50 AM, John Clements wrote:

> In PLT Scheme (and most other computer languages), it's possible to represent multiple values as a single value using the notion of "compound data" (also known as structures, classes, tuples, records, dicts, and so on and so forth).
> ...
> I was about to write more, but honestly I should just give you this URL:
> http://www.htdp.org/2003-09-26/Book/curriculum-Z-H-9.html#node_chap_6
> It's about the topic you mentioned, and the chance that my text will be better than HtDP is fairly small. Take a look.

One warning: the Chapter 6 linked to above uses the old "draw" graphics library fairly heavily, and most people teaching this material have stopped using it in favor of the more up-to-date "image", "world", and/or "universe" libraries.  (One can teach structures without graphics at all, but graphics seem to be a good way to motivate the concepts.)

You might want to take a look, instead, at


which is the corresponding chapter in the not-yet-finished Second Edition of HtDP.  Or the corresponding chapters in my textbook, which isn't on the Web yet but which I can e-mail you if you wish.

Stephen Bloch
sbloch at adelphi.edu

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