return new value that was added to the cache

i thought swap! was supposed to return this value by itself?

src/blarg/models/posts.clj

@@ -15,8 +15,10 @@
   (let [cached-post (get @post-md-cache _id)]
     (if (or (not cached-post)
             (after? created_at (:created_at cached-post)))
+      (do
         (swap! post-md-cache assoc _id {:created_at created_at
                                         :html_body (md->html body)})
+        (get @post-md-cache _id))
       cached-post)))
 
 (defn- merge-cached-post-md! [post]