Hoplon rot13

rot13.cljs.hl

(page "rot13.html")

(defn make-rot13 [start]
  (->> (for [from (range 27),
             :let [to (mod (+ 13 from) 26)]]
         [(char (+ start from)) (char (+ start to))])
       (into {})))

(let [table (merge (make-rot13 97) (make-rot13 65))]
  (defn rot13 [s]
    (get table s s)))

(html
  (head
    (link :rel "stylesheet" :type "text/css" :href "css/main.css"))
  (body
    (let [plaintext (cell "")
          encoded   (cell= (apply str (map rot13 plaintext)))]
      (div
        (input
          :type "text"
          :input #(reset! plaintext (.val (js/jQuery (.-target %)))))
        (span encoded)))))

Thanks, @alandipert! My latest version benefited greatly from this example:
https://github.com/r0t13/rot13.io/blob/hoplon/src/index.cljs.hl

Oh, and I caught an off-by-one bug on line 4: with 27 instead of 26, [ and { get included by mistake.