anchor.diff:      #state{ets=?ETS, types=?LATTICES, store=dict:new()}.
   
   %% Generate commands
  -command(#state{ets=Ets, types=Types, store=Store}) ->
  +command(#state{ets=Ets, types=_Types, store=Store}) ->
       Variables = dict:fetch_keys(Store),
       oneof(
  -        [{call, ?MODULE, declare,
  -          [oneof([elements(Types), undefined]), Ets]}] ++
  +        [{call, ?MODULE, declare, [undefined, Ets]}] ++
  +        % [{call, ?MODULE, declare,
  +        %   [oneof([elements(Types), undefined]), Ets]}] ++
           [{call, ?MODULE, read,
             [elements(Variables), undefined, Ets]} || length(Variables) > 0] ++
           [?LET({Variable, GeneratedValue}, {elements(Variables), nat()},
  
positive.code:                 setup(),
                  fun teardown/0
             end,
          ?FORALL(Cmds, commands(?MODULE),
                  begin
                      {H, S, Res} = run_commands(?MODULE, Cmds),
                      ?WHENFAIL(
  
negative.code:             true;
          {ok, #variable{value=Value}} ->
              %% Already bound to same value.
              true;
          {ok, _} ->
              %% Bound, to different value.
              true;
  