anchor.diff:      ephp_context:set_output(Context, <<"Array\n(\n", Data/binary, ")\n">>),
       null.
   
  +-spec isset(Context :: context(), Value :: mixed()) -> boolean().
  +
  +isset(_Context, Value) ->
  +    case Value of
  +        undefined -> false;
  +        _ -> true
  +    end.
  +
  +-spec empty(Context :: context(), Value :: mixed()) -> boolean().
  +
  +empty(_Context, Value) ->
  +    case Value of
  +        undefined -> true;
  +        <<"0">> -> true;
  +        <<>> -> true;
  +        false -> true;
  +        _ -> false
  +    end.
  +
   %% ----------------------------------------------------------------------------
   %% Internal functions
   %% ----------------------------------------------------------------------------
  
positive.code:     init/1,
      is_bool/2,
      print_r/2,
      print_r/3
  ]).
  
  -include("ephp.hrl").
  
negative.code: 
  init(Context) ->
      Funcs = [
          is_bool, print_r, isset, empty
      ],
      lists:foreach(fun(Func) ->
          Name = atom_to_binary(Func, utf8),
  