NFD » ndn-cxx

ScopedEventId can be useful in many other places besides NFD. The only difference that ScopedEventId in the library should not be tied to global scheduler instance.

As a result, there is interface change and one interface limitation (no longer possible to implicitly convert EventId to ScopedEventId).
Here is a modified version of API:

/** \brief Event that is automatically cancelled upon destruction
 */
class ScopedEventId : noncopyable
{
public:
  /** \brief Construct ScopedEventId tied to the specified scheduler
   *  \param scheduler Scheduler to which the event is tied
   */
  ScopedEventId(Scheduler& scheduler);

  /** \brief move constructor
   */
  ScopedEventId(ScopedEventId&& other);

  /** \brief assigns an event
   *
   *  If a different event has been assigned to this instance previously,
   *  that event will be cancelled immediately.
   *
   *  \note The caller should ensure that ScopedEventId is tied to a correct scheduler.
   *        Behavior is undefined when assigning event scheduled in another scheduler instance.
   */
  ScopedEventId&
  operator=(const EventId& event);

  /** \brief cancels the event
   */
  ~ScopedEventId();

  /** \brief cancels the event manually
   */
  void
  cancel();

  /** \brief releases the event so that it won't be disconnected
   *         when this ScopedEventId is destructed
   */
  void
  release();

private:
  Scheduler* m_scheduler; // pointer to allow move semantics
  EventId m_event;
};