anchor.diff:  
   %% @doc Returns a list of terms with duplicates removed.
   -spec uterms(utf8_string(), iso_639_1()) -> [utf8_string()].
  -uterms(Str, Lang) ->
  +uterms(Text, Lang) ->
  +    Str = expand(Text, Lang),
       plists:usort(
         plists:map(
           fun (T) -> (list_to_atom("doko_stemming_" ++ Lang)):stem(T) end,
  
positive.code: %%----------------------------------------------------------------------------
  %% Internal functions
  %%----------------------------------------------------------------------------
  
  tokenize(Str, Lang) ->
      RE = case Lang of
  
negative.code: 
  %% API
  -export([uterms/2]).
  -export([expand/2]).
  
  %%----------------------------------------------------------------------------
  %% API
  