when-let-lol.clj

(defroutes chapter-routes
  ;; Example story-slug:   42-my-first-story
  ;; Example chapter-slug: 99-introduction
  ;; (util/parse-uid "42-my-first-story") -> 42
  ;; (util/parse-uid "99-introduction")   -> 99
  (GET "/chapters/:chapter-slug" [story-slug chapter-slug]
    (when-let [story-uid (util/parse-uid story-slug)]
      (when-let [chapter-uid (util/parse-uid chapter-slug)]
        (when-let [story (db/find-story-by-uid story-uid)]
          (when-let [chapter (db/find-chapter-by-uid chapter-uid)]
            (-> (zizkov.views/show-chapter story chapter)
                layout))))))
  )