Dissociates an entry from a nested associative structure returning a new
nested structure. keys is a sequence of keys. Any empty maps that result
will not be present in the new structure.
(defn dissoc-in
"Dissociates an entry from a nested associative structure returning a new
nested structure. keys is a sequence of keys. Any empty maps that result
will not be present in the new structure."
[m [k & ks :as keys]]
(if ks
(if-let [nextmap (get m k)]
(let [newmap (dissoc-in nextmap ks)]
(if (seq newmap)
(assoc m k newmap)
(dissoc m k)))
m)
(dissoc m k)))