anchor.diff:  labels_string([])     -> "";
   labels_string(Labels) ->
     Fun = fun (#'LabelPair'{name=Name, value=Value}) ->
  -            io_lib:format("~s=\"~s\"", [Name, escape_label_value(Value)])
  +            [Name, "=\"", escape_label_value(Value), "\""]
           end,
  -  "{" ++ string:join(lists:map(Fun, Labels), ",") ++ "}".
  +  ["{", lists:join(",", lists:map(Fun, Labels)), "}"].
   
   emit_series(Fd, Name, Labels, undefined) ->
     LString = labels_string(Labels),
  -  file:write(Fd, io_lib:format("~s" ++ LString ++ " NaN\n", [Name]));
  +  file:write(Fd, [Name, LString, " NaN\n"]);
   emit_series(Fd, Name, Labels, Value) ->
     LString = labels_string(Labels),
  -  file:write(Fd, io_lib:format("~s" ++ LString ++ " ~p\n", [Name, Value])).
  +  file:write(Fd, [Name, LString, " ", io_lib:format("~p", [Value]) , "\n"]).
   
   %% @private
   escape_metric_help(Help) ->
     sub(sub(Help, "\\", "\\\\\\\\"), "\n", "\\\\n").
   
   bound_to_label_value(Bound) when is_number(Bound) ->
  -  Bound;
  +  io_lib:format("~p", [Bound]);
   bound_to_label_value(infinity) ->
     "+Inf".
   
  
positive.code:                  registry_collect_callback(Fd, Registry, Collector)
               end,
    prometheus_registry:collect(Registry, Callback),
    file:write(Fd, io_lib:format("\n", [])),
    {ok, Size} = ram_file:get_size(Fd),
    {ok, Str} = file:pread(Fd, 0, Size),
    ok = file:close(Fd),
  
negative.code:   ?ESCAPE_LVALUE(LValue);
  escape_label_value(LValue) when is_binary(LValue) ->
    ?ESCAPE_LVALUE(LValue);
  escape_label_value(Value) ->
    erlang:error({wtf, Value}).
  
  
  -spec sub(iodata(), string(), string()) -> string().
  sub(Str, Old, New) ->
  