anchor.diff:         true -> t_limit_k(Termination, K - 1)
       end,
     NewElements = t_limit_k(Elements, K - 1),
  -  TmpList = t_cons(NewElements, NewTermination),
  -  case Size of
  -    ?nonempty_qual -> TmpList;
  -    ?unknown_qual ->
  -      ?list(NewElements1, NewTermination1, _) = TmpList,
  -      ?list(NewElements1, NewTermination1, ?unknown_qual)
  -  end;
  +  ?list(NewElements, NewTermination, Size);
   t_limit_k(?function(Domain, Range), K) ->
     %% The domain is either a product or any() so we do not decrease the K.
     ?function(t_limit_k(Domain, K), t_limit_k(Range, K-1));
  
positive.code: t_subst_aux(?list(Contents, Termination, Size), Map) ->
    case t_subst_aux(Contents, Map) of
      ?none -> ?none;
      NewContents ->
        %% Be careful here to make the termination collapse if necessary.
        case t_subst_aux(Termination, Map) of
  
negative.code:     end,
    NewContents = t_sup(Contents1, Contents2),
    NewTermination = t_sup(Termination1, Termination2),
    ?list(NewContents, NewTermination, NewSize);
  t_sup(?number(_, _), ?number(?any, ?unknown_qual) = T) -> T;
  t_sup(?number(?any, ?unknown_qual) = T, ?number(_, _)) -> T;
  t_sup(?float, ?float) -> ?float;
  