Yeah, the Wikibook version is more actively maintained. I haven't really touched the original in about 3 years. I keep meaning to revisit it and include some of the stuff I've learned in the intervening time (LLVM codegen and JIT, for example), but I've got way too many other projects that are occupying my time...
This is great! I love the idea of doing something both challenging and interesting in order to learn a language. I belong in that first group (know Scheme but know very little Haskell) so this is perfect for me :)
Is there a tutorial on testing in Haskell that you would recommend to go along with this?
When I was in high school I wrote a subroutine threaded FORTH for OS-9 on the TRS-80 color computer; it was 2000 lines of assembly code and it (almost) worked right the first time.
When I was in junior high school I wrote a fully functioning perl on the TI-80 graphing calculator. It was about 200 lines of code, and it (almost) worked right the first time.
http://en.wikibooks.org/wiki/Write_Yourself_a_Scheme_in_48_H...
Also, there you can download PDF.