Generators without generators

gistfile1.txt

function generator(func) {
  var statefulArg;
  
  return function() {
    statefulArg = statefulArg || arguments[0];
    
    statefulArg = func.apply(this, [statefulArg]);

    return statefulArg
  };
}
  
function double(numberToDouble) {
  return numberToDouble * 2;
}
  
generatorDouble = generator(double);

generatorDouble(1); // 2
generatorDouble(); // 4
generatorDouble(); // 8

Actually is iterator :\