How to implement Python-style generator in Scheme (Racket or ChezScheme)?

Question

today I solve the N-queen problem using Scheme but it is extremely slow compared to the same version of Python. when N = 8, Scheme takes 90+ seconds! I know one reason is th

Answer 1

I have found that do performs significantly more quickly than iterating over a list:

(do ((i 0 (add1 i)))
  ((= i 100000) 'result)
   (some-function! i some-data))

If you want to be more functional the Racket documentation suggests in-list for use with for and it's variants.

(for/list ((i (in-list (range 0 100000))))
  (some-function i some-data))