(let [user {name Ada} changed (put (collections/copy .user) name Bea)] [.user .changed])
(let
  [root
   {settings {theme light}}
   changed
   (put (collections/copy .root) (jsonptr "/settings/theme") dark)]
  [.root .changed])
(let
  [root {users [{name Ada}]} changed (put (collections/copy .root shallow) [users 0 name] Bea)]
  [.root .changed])
(let
  [root {users [{name Ada}]} changed (put (collections/copy .root shallow) users [])]
  [.root .changed])