anchor.diff:  -record(state, {child_module :: atom(),
                   child_state :: term(),
                   path :: string(),
  -                name :: atom()}).
  +                name :: atom(),
  +                revisions :: term()}).
   
   -record(doc, {id :: term(),
                 rev :: term(),
  
positive.code:            child_module = ChildModule,
             child_state = ChildState}.
  
  init_after_ack(State) ->
      ok = open(State),
      State.
  
  open(#state{path = Path, name = TableName}) ->
      {ok, TableName} =
          dets:open_file(TableName,
                         [{type, set},
  
negative.code: 
  save_docs(Docs, #state{name = TableName,
                         child_module = ChildModule,
                         child_state = ChildState,
                         revisions = Revisions} = State) ->
      ok = dets:insert(TableName, Docs),
      true = ets:insert(Revisions, [{Doc#doc.id, Doc#doc.rev} || Doc <- Docs]),
      lists:foreach(fun (#doc{id = Id, deleted = true}) ->
                            _ = mru_cache:delete(TableName, Id);
                        (#doc{id = Id, deleted = false, value = Value}) ->
  