Tweak get-in behavior
a sequence of keys.`
[ds ks &opt dflt]
(var d ds)
- (loop [k :in ks :while d] (set d (get d k)))
+ (loop [k :in ks :while (not (nil? d))] (set d (get d k)))
(if (= nil d) dflt d))
(defn update-in
