[Cs254f11] lets that depend on other things that have been let in the same context

[Wm. Josiah Erikson]

I find it annoying, just for readability of my program and not having to 
do things over and over again, that I can't do this:

(defn prediction-test
   [psize gens]
   (let [best-fit (evolve_best_fit psize gens)]
     [reference-error (error best-fit)]
     [test-error (test_error best-fit)]
     [error-difference (Math/abs (- reference-error test-error))]
     (println "The shortest best fit individual over" gens "generations 
with a population size of" psize)
     (println "was" best-fit)
     (println "It had an error of" reference-error "against the 
reference songs, and an error of")
     (println test-error "against the test songs, giving a difference 
of" error-difference)))

It tells me that it can't resolve the symbol reference-error in this 
context. I assume that this is because it defines those out of order or 
something. But why didn't it complain about not knowing what best-fit 
was first?

Am I doing this wrong, or can you just not do this?

-- 
Wm. Josiah Erikson
Network Engineer
Hampshire College
Amherst, MA 01002
(413) 559-6091