public StateMachineEventActivitiesBuilder <TInstance> Initially()
        {
            var builder = new InternalStateMachineEventActivitiesBuilder <TInstance>(_machine, this,
                                                                                     activities => _machine.Initially(activities));

            _activityBuilders.Add(builder);
            return(builder);
        }
        public StateMachineEventActivitiesBuilder <TInstance> During(params State[] states)
        {
            var builder = new InternalStateMachineEventActivitiesBuilder <TInstance>(_machine, this,
                                                                                     activities => _machine.During(states, activities));

            _activityBuilders.Add(builder);
            return(builder);
        }