varargs + recur

gistfile1.clj

;; Could do this
(defn add* [[x & more] total]
  (if-not x
    total
    (recur more (+ x total ))))

(defn add1 [& xs]
  (add* xs 0))

;; I'd do this
(defn add2 [& xs]
  (loop [[x & more] xs
         total 0]
    (if-not x 
      total
      (recur more (+ x total)))))