clojure.clj

(defn +
  "Returns the sum of nums. (+) returns 0. Does not auto-promote
  longs, will throw on overflow. See also: +'"
  {:inline (nary-inline 'add 'unchecked_add)
   :inline-arities >1?
   :added "1.2"}
  ([] 0)
  ([x] (cast Number x))
  ([x y] (. clojure.lang.Numbers (add x y)))
  ([x y & more]
(reduce1 + (+ x y) more)))

ferret.clj

(defn +
  ([] 0)
  ([x] x)
  ([h v]
   "__result = h.cast<number>()->add(v);")
  ([x y & more]
   (reduce + (+ x y) more)))