What is the idiomatic way to swap two elements in

问题:

Is there a better or more concise way to do the following?

(defn swap [v i1 i2]
  "swap two positions in a vector"
  (let [e1 (v i1)
        e2 (v i2)]
       (-> (assoc v i1 e2)
       (assoc i2 e1))))

回答1:

I can't think of a particularly elegant solution, either. Here's how I'd write it though:

(defn swap [v i1 i2] 
   (asso­c v i2 (v i1) i1 (v i2)))­