[stiff]

Writing a Lisp interpreter is an opportunity to write a really beautiful program, do not waste it by stopping at a first version that sort of works. A nice implementation should read almost like a spec of the language, except maybe for the more prosaic parsing part. Look at the Norvig article, or at the implementation of Ian Piumarta for inspiration:

http://piumarta.com/software/lysp/lysp-1.1/lysp.c

[magal]

Or Chaitin's http://www.umcs.maine.edu/~chaitin/lisp.c

[kaoD]

Yeah but... which spec?

(pun intended)