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I'm trying to write a function that returns a memoized recursive function in Clojure, but I'm having trouble making the recursive function see its own memoized bindings. Is this because there is no var created? Also, why can't I use memoize on the local binding created with let? This slightly unusual Fibonacci sequence maker that starts at a particular number is an example of what I wish I could do: (defn make-fibo [y] (memoize (fn fib [x] (if (< x 2) y (+ (fib (- x 1)) (fib (- x 2))))))) (let [f (make-fibo 1)] (f 35)) ;; SLOW, not actually memoized Using with-local-vars seems like the right approach, but it doesn't work for me either. I guess I can't close over vars? (defn make-fibo [y] (with-local-vars [fib (fn [x] (if (< x 2) y (+ (@fib (- x 1)) (@fib (- x 2)))))] (memoize fib))) (let [f (make-fibo 1)] (f 35)) ;; Var null/null is unbound!?! I could of course manually write a macro that creates a closed-over atom and manage the memoization myself, but I was hoping to do this without such hackery.

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