More interning with Clojure

with-intern.clj

(defmacro with-interns
  "interns => [intern1 intern2...]
   Evaluates body while making available many functions, bound to the 
   symbols in interns. Each fn, when called, returns a deduped reference to
   its argument. The deduplication is with respect to any previously-called
   arguments to that fn.

   (with-interns [intern]
     (into {} 
       (for [k (range 100000)]
         [k (intern (vec (repeatedly 3 #(rand-int 10))))])))"
  
  [interns & body]
  (cond (= (count interns) 0) 
          `(do ~@body)
        (symbol? (interns 0)) 
          `(let [intern# (atom #{})
                ~(interns 0) #(get @intern# % (get (swap! intern# conj %) %))]
             (with-interns ~(subvec interns 1) ~@body))))