reshape_data.cljs

(def some-data
  [{:id :fruits
    :title "Fruits"
    :types [{:id :apple :title "Apple"}
            {:id :orange :title "Orange"}
            {:id :banana :title "Banana"}]}
   {:id :vegetables
     :title "Vegetables"
     :types [{:id :tomato :title "Tomato"}
             {:id :carrot :title "Carrot"}
             {:id :banana :title "Cucumber"}]}
   {:id :meats
     :title "Meats"
     :types [{:id :beef :title "Beef"}
             {:id :chicken :title "Chicken"}
             {:id :pork :title "Pork"}]}])
 
; Desired shape 
; [["Apple" :apple]["Orange" :orange]["Banana" :banana]["Tomato" :tomato]["Carrot" :carrot] ...]

;; Attempt
(def reshape-some-data 
  (for [group nav-data
         :let [sections (:sections group)]]
        (for [sec sections
              :let [id (:id sec)
                    title (:title sec)]]
          [title id])))

; Current shape - NO GOOD!
; ((["Apple" :apple]["Orange" :orange]["Banana" :banana]) (["Tomato" :tomato]["Carrot" :carrot] ...))

In a previous attempt I used mapv instead of for to iterate over the data but the result was similar.
[[["Apple" :apple]["Orange" :orange]["Banana" :banana]] [["Tomato" :tomato]["Carrot" :carrot] ...]]

(mapcat (fn [m] (map (fn [n] [(:title n) (:id n)]) (:types m))) some-data)
or

(def reshape-some-data
  (apply concat (for [group some-data
                      :let [sections (:types group)]]
                  (for [sec sections
                        :let [id (:id sec)
                              title (:title sec)]]
                    [title id]))))