anchor.diff:      [${, write_list(L, $,), $}];
   write({{list, L}, _}) ->
       [$[, write_list(L, $|), $]];
  +write({{map, Pairs}, _}) ->
  +    [$#,${, write_list(Pairs, $,), $}];
  +write({{map_pair, K, V}, _}) ->
  +    [write(K)," => ",write(V)];
   write({{record, [{Name,_} | L]}, _}) ->
       [Name, ${, write_fields(L), $}];
   write({{bin, S}, _}) ->
  
positive.code:     [${, pp_tag_tuple(L, Col, Ll, M, TInd, Ind, LD, W + 1), $}];
  pp({{tuple,false,L}, _Len}, Col, Ll, M, TInd, Ind, LD, W) ->
      [${, pp_list(L, Col + 1, Ll, M, TInd, indent(1, Ind), LD, $,, W + 1), $}];
  pp({{record,[{Name,NLen} | L]}, _Len}, Col, Ll, M, TInd, Ind, LD, W) ->
      [Name, ${, pp_record(L, NLen, Col, Ll, M, TInd, Ind, LD, W + NLen+1), $}];
  pp({{bin,S}, _Len}, Col, Ll, M, _TInd, Ind, LD, W) ->
  
negative.code:     {"[]", 2};
  print_length({}, _D, _RF, _Enc, _Str) ->
      {"{}", 2};
  print_length(#{}=M, _D, _RF, _Enc, _Str) when map_size(M) =:= 0 ->
      {"#{}", 3};
  print_length(List, D, RF, Enc, Str) when is_list(List) ->
      case Str andalso printable_list(List, D, Enc) of
          true ->
  