Clojurians Log v2

Hmmm I seem to recall some docs on type 2 components but I can't find them

I'm basically trying to build the following combobox component that lets you select from a list but then edit the selection:

(defn dbfield [typ props st valfn changefn]
  (let [int (r/atom @st)
        ext (r/atom @st)
        dbfn (debounce changefn)]
    (fn [typ props st valfn changefn]
      (when (not= @ext @st)
        (reset! int @st)
        (reset! ext @st))
      [typ (assoc props
                  :value (valfn @int)
                  :on-change (fn [e]
                               (let [val (.. e -target -value)]
                                 (dbfn st val)
                                 (changefn int val))))])))

(defn combobox-cursors [vector-cursor]
  (let [index-cursor (r/atom 0)
        element-cursor (r/cursor vector-cursor [@index-cursor])]
    [element-cursor index-cursor vector-cursor]))

(defn combobox-field [[element-cursor index-cursor vector-cursor] valfn changefn]
  [:div.combobox-group
   [dbfield :input {:class "combobox-input"} element-cursor valfn changefn]
   [:select {:class "combobox-select"
             :value @index-cursor
             :on-change #(reset! index-cursor (js/parseInt (.. % -target -value)))}
    (doall (map-indexed 
             (fn [i item]
               [:option {:key i :value i} (valfn item)])
             @vector-cursor))]])

I thought, I know I'll use a type 2 component and put all those state atoms outside so they don't get reset. But as I said the vector-cursor does depend on other things so if you put them outside they never update at all.