anchor.diff:  
   post(Feed, Text) ->
       gen_server:call(?MODULE, {post, Feed, Text}).
  +
  +comment(PostID, Text) ->
  +    gen_server:call(?MODULE, {comment, PostID, Text}).
   
   is_logged_in() ->
       gen_server:call(?MODULE, {is_logged_in}).
  
positive.code:     {reply, Status, NewState};
  handle_call({post, Feed, Text}, _From, State) ->
      Status = post(Feed, Text, State),
      {reply, Status, State};
  handle_call({is_logged_in}, _From, State) ->
      {reply, State#state.logged_in, State};
  
negative.code:     Response = jiffy:decode(Data, [return_maps]),
      #{<<"posts">> := Posts} = Response,
      Posts.
  
  comment(PostID, Text, State) ->
      Token = State#state.token,
      Request = #{
          <<"comment">> => #{
              <<"body">> => Text,
              <<"postId">> => PostID
          }
      },
      RequestJSON = jiffy:encode(Request),
      io:format(RequestJSON),
      {ok, {StatusCode, _Headers, Data}} = httpc:request(
          post,
          {
              "https://freefeed.net/v1/comments/",
              [{"x-authentication-token", binary_to_list(Token)}],
              "application/json",
              RequestJSON
          },
          [],
          []
      ),
      {StatusCode, Data}.
  