anchor.diff:      nolong}
      ].
   
  +synonyms() ->
  +  [{observers, use_receive_patterns}].
  +
   multiple_allowed() ->
     [ exclude_module
     , ignore_error
  
positive.code:     [ fun proplists:unfold/1
      , fun set_verbosity/1
      , fun assert_tuples/1
      , fun open_files/1
      , fun add_to_path/1
      , fun add_missing_file/1
  
negative.code:       Error = "Malformed option: ~w",
        opt_error(Error, [T], input)
    end.
  
  %%%-----------------------------------------------------------------------------
  
  fix_synonyms(Options) ->
    Map =
      fun(Key) ->
          hd([R || {K, R} <- synonyms() ++ [{Key, Key}], K =:= Key])
      end,
    lists:keymap(Map, 1, Options).
  
  %%%-----------------------------------------------------------------------------
  
  