[plt-scheme] STICCS, a Scheme App

The Link: <http://dl.aaronhsu.com/src/sticcs.tar.gz>

Alright everyone, I have been developing a program for a contract 
client for a few weeks now, and I have finally reached a point where 
I feel comfortable calling it "Early Beta." I think it's time to release it 
out for "testing only" to the public. I can't recommend and highly 
discourage any real uses for right now.

The name: STICCS, which stands for the "Scheme TIme Code 
Calculator: STICCS". ;-) I couldn't resist.

Basically, it's exactly like a normal calculator except that it handles 
timecodes, such as 1 hour, 4 minutes, 13 seconds, and 20 frames.

One neat feature of this Calculator is that it is completely 
compatible with RPN and Algebraic notation. You can mix and 
match however you want, using RPN for one calculation, and using 
those results in an Algebraic form later on. There are some 
limitations, of course, but I'll fix those soon enough. :-)

It also has an editable tape, which means that you can annotate 
while you work, and then copy and paste the whole shebam into 
another program after you are done.

It can be partially run by the keyboard through the number pad right 
now. The E [Clear all], D [delete last entry], and C [Clear input], are 
not accessible through the keyboard yet.

In addition, it supports Drop frames, though I have not yet 
determined if the values reported are correct or not. This is the part 
I would really like to test.

The entire program is done almost entirely in R5RS Scheme, 
except for the GUI and parts which use the GUI, which have been 
done in PLT Scheme. 

Right now it is quite far from perfect, and I realize there are many 
"effeciency errors." I intend to fix those I can, but I would like to 
hear just the same from all of you what I could or could not 
improve. If you see anything well implemented, tell me that as well, 
so that I can use the same techniques in the future.

No doubt to you experienced programmers, this will seem 
pretty...ehem...ugly, but I'm hoping to get better with some help. 
Unfortunately, only the back-end is commented, and none of the 
front-end. I intend to remedy that as well.

I would appreciate suggestions and assistance. :-)

I must say that this is quite a learning experience, even getting it to 
this point.

You can download the application source from: 
<http://dl.aaronhsu.com/src/sticcs.tar.gz>

Thanks a bunch,

- Aaron Hsu <af at aaronhsu.com>