This is a brief introduction to Python for Lisp programmers. (Although it wasn't my intent, Python programers have told me this page has helped them learn Lisp.) Basically, Python can be seen as a dialect of Lisp with "traditional" syntax (what Lisp people call "infix" or "m-lisp" syntax). One message on comp.lang.python said "I never understood why LISP was a good idea until I started playing with python." Python supports all of Lisp's essential features except macros, and you don't miss macros all that much because it does have eval, and operator overloading, and regular expression parsing, so you can create custom languages that way.
CL-XML is a collection of Common LISP modules for data stream parsing and serialization according to the "Extensible Markup Language" and anscilliary standards. The modules perform parsing and serialization between XML, XML Query, and XML Path expressions and DOM-compatible CLOS instances.
FReT is a common lisp package for testing common lisp software. Version 0.3 is at present at least as functional as any such software publically available, but still far from complete.
I take you on a simple stroll through Lisp's basic constructs and then ramp up quickly. You'll see Lambda expressions, recursion, and macros. This quick tour should give you an appreciation of Lisp's productivity and flexibility.
What should you learn first, Lisp or Haskell? It depends entirely on your personality. One thing is certain - if you want to be a great developer eventually you'll have to learn both.
In analyzing my data I wanted to classify it with a naive Bayesian classifier. I wasn't sure I had the math right, so I wrote a tiny abstract classifier to test with. The code is pretty cool:
N. Borenstein, und J. Gosling. Proceedings of the 1st Annual ACM SIGGRAPH Symposium on User Interface Software, Seite 95--101. New York, NY, USA, ACM, (1988)
R. Brooks, R. Gabriel, und G. Steele Jr.. International Joint Conference on Artificial Intelligence, 2, Seite 845--849. Karlsruhe, West Germany, William Kaufman, (August 1983)
R. Brooks, R. Gabriel, und J. Steele. LFP '82: Proceedings of the 1982 ACM symposium on LISP and functional programming, Seite 108--113. New York, NY, USA, ACM, (1982)
R. Gabriel. Proceedings of the 2016 ACM International Symposium on New Ideas, New Paradigms, and Reflections on Programming and Software, Seite 250--268. New York, NY, USA, ACM, (2016)