anchor.diff:  init([Pid]) ->
     {ok, Pid}.
   
  -handle_event({reload, File}, Pid) ->
  -  Pid ! {reload, File},
  +handle_event(Event, Pid) ->
  +  Pid ! Event,
     {ok, Pid}.
   
   handle_call(_, Pid) ->
  
positive.code: reload(File) ->
    gen_event:notify(?MODULE, {reload, File}).
  
  init(_TransportName, Req, Opts) ->
    case cowboy_req:header(<<"upgrade">>, Req) of
      {<<"websocket">>, _} ->
  
negative.code:   liveCSS => true
  })).
  
  -define(ALERT(Message), jsxn:encode(#{
    command => alert,
    message => Message
  })).
  
  websocket_init(_TransportName, Req, Opts) ->
    {ok, Req, Opts}.
  
  