anchor.diff:  %%   Path   = [b, c]
   %%   Params = [y, b, c]
   refine_params([], Params) -> 
  -    [V || {_, V} <- Params];
  +    [wf:to_list(V) || {_, V} <- Params];
   refine_params([H|T], Params) ->
       F = fun({Path, Value}, Acc) ->
           case split_on(H, Path) of
  
positive.code:     F = fun({KeyPartsReversed, Value}) ->
          KeyParts = lists:reverse(KeyPartsReversed),
          Key = string:join(KeyParts, "."),
          { Key, Value }
      end,
      lists:map(F, Params).
  
  
negative.code: get_value(Path, Config, State) ->
      case get_values(Path, Config, State) of
          [] -> undefined;
          [One] -> wf:to_list(One);
          _Many -> throw({?MODULE, too_many_matches, Path})
      end.
  
  