anchor.diff:      skip_whitespace(Rest, ?INC_CHAR(S, C));
   skip_whitespace(Rest, S) ->
       {Rest, S}.
  +
  +find_qgt([], S) ->
  +    {[], S};
  +find_qgt("?>" ++ Rest, S) ->
  +    {Rest, ?ADV_COL(S, 2)};
  +find_qgt([C | Rest], S) ->
  +    find_qgt(Rest, ?INC_CHAR(S, C)).
   
   find_gt([], S, HasSlash) ->
       {[], S, HasSlash};
  
positive.code: %% @spec parse_tokens([html_token()]) -> html_node()
  %% @doc Transform the output of tokens(Doc) into a HTML tree.
  parse_tokens(Tokens) when is_list(Tokens) ->
      %% Skip over doctype
      F = fun (X) ->
                  case X of
                      {start_tag, _, _, false} ->
  
negative.code:     tree(Rest, append_stack_child(norm({Tag, Attrs}), S));
  tree([{start_tag, Tag, Attrs, false} | Rest], S) ->
      tree(Rest, stack(norm({Tag, Attrs}), S));
  tree([T={pi, _Tag, _Attrs} | Rest], S) ->
      tree(Rest, append_stack_child(T, S));
  tree([T={comment, _Comment} | Rest], S) ->
      tree(Rest, append_stack_child(T, S));
  tree(L=[{data, _Data, _Whitespace} | _], S) ->
  