anchor.diff:          _ when is_atom(ModOrFile) ->
               Fs=[F||F<-Files, filename:basename(F,".erl")==atom_to_list(ModOrFile)],
               case Fs of 
  -                [] -> [];
  +                [] -> error("None of the files specified in the "
  +                            "searchpaths matches the module name given.");
                   [F|_] -> [F]
               end;
           _ when is_list(ModOrFile)->
  
positive.code:     Res= gen_file_names(ModOrFile, SearchPaths),
      case Res of 
          [] ->
              {error, lists:flatten(
                        io_lib:format("File/Module does not exist in the "
                                      "searchpaths specified: ~p.\n", 
                                      [ModOrFile]))};
          [File] ->
              File;
          [File|_] ->
              {error, lists:flatten(
                        io_lib:format("File/module specified is not unique "
                                      "in the searchpaths specified.:~p\n", 
                                      [File]))}
      end.
  
  
  
negative.code:                 true ->
                      [ModOrFile];
                  false ->
                      throw({error, lists:flatten(
                                      io_lib:format(
                                        "Invalid argument:~p.", [ModOrFile]))})
              end;
          _ -> 
              throw({error, lists:flatten(io_lib:format(
                                            "Invalid argument:~p.", [ModOrFile]))})
      end.
  
  get_next_file([], _FileOrModFilter) -> [];
  