anchor.diff:  -behaviour(gen_server).
   
   %% API
  --export([start_link/1,source/1,run/1,register/2,register/3,alias/3,global/1,global/2,add_handler/3]).
  +-export([start_link/1,source/1,run/1,register/2,register/3,alias/3,global/1,global/2,add_handler/3,stop/1]).
   
   %% gen_server callbacks
   -export([init/1, handle_call/3, handle_cast/2, handle_info/2,
  
positive.code: 	Reply = erlv8_nif:set_global(Script, Global),
  	{reply, Reply, State};
  
  handle_call(_Request, _From, State) ->
  	{noreply, State}.
  
  
negative.code: 
  global(Server, Global) when is_list(Global) ->
  	gen_server:call(Server, {global, Global}).
  
  stop(Server) ->
  	gen_server:call(Server,stop).
  