Genetic programming: pygene, pygp, AST, or (gasp) Lisp?

[John Ladasky]

Thanks to everyone who replied.  I haven't chosen a definite direction
for my project yet.  But you have given me some good leads.

Google Books offers previews of many pages of John Koza's book,
published in the early 1990's.  I'm reading through the preview pages,
with the idea of purchasing a more recent book on the subject once I
understand the subject a bit better.

Apropos to Python, I've had a quick look at the parse and compile
functions in Python's compiler module.  The Python AST is MUCH longer
than I expected it to be, for just a few lines of code.  It may
contain more information than I need.  I'll see whether I can make
sense of EasyExtend or Dione next.