(let fib (function int [int y function fib]
    (let retval 0)
    (if (== 1 y) (set retval 0))
    (if (== 2 y) (set retval 1))
    (if (> y 2) 
        (set retval (+ (fib (- y 1) fib) (fib (- y 2) fib)))
    )
    (return retval)
))

(print (fib 30 fib))