anchor.diff:  				   token_filter = TokenFilter}) ->
       M1 = translate_char_filter(CF, #{}),
       M2 = translate_tokeizer(Tokenizer, M1),
  -    make_token_filter(TokenFilter, M2).
  +    make_token_filter(TokenFilter, M2);
  +make_index_options(undefined) ->
  +    undefined.
   
   translate_char_filter('NFC', M) ->
       M#{char_filter => nfc};
  
positive.code: translate_posting_filter(undefined) ->
      undefined;
  translate_posting_filter(#'PostingFilter'{sort_by = 'RELEVANCE',
  					  start_ts = 0,
  					  end_ts = 0,
  					  max_postings = 0}) ->
      undefined;
  translate_posting_filter(#'PostingFilter'{sort_by = SortBy,
  
negative.code: 					  end_ts = EndTs,
  					  max_postings = MaxPostings}) ->
      M1 = translate_sort_by(SortBy, #{}),
      M2 = set_value(start_ts, decode_unsigned_default(StartTs, undefined), M1),
      M3 = set_value(end_ts, decode_unsigned_default(EndTs, undefined), M2),
      set_value(max_postings, MaxPostings, M3).
  
  decode_unsigned_default(<<>>, Default) ->
      Default;
  decode_unsigned_default(Bin, _) when is_binary(Bin) ->
      binary:decode_unsigned(Bin, big);
  decode_unsigned_default(_, Default) ->
      Default.
  
  translate_sort_by('RELEVANCE', M) ->
      M#{sort_by => relevance};
  