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quietbritishjim • today at 7:47 AM • 2 replies • view on HN

That doesn't work if you are writing a library where users of the library are able to implement their own event types.

Even for a self-contained code base, it's a pain compared to a type that just works with any current or future derived class.

Replies

nananana9 • today at 7:57 AM

It does.

  enum EventType {
     ...,
     EVENT_USER_START = 0xF0000000,
  };
  struct UserEventData { uint8 placeholder[64]; }
  struct Event {
     EventType type;
     union {
         UserEventData user;
     };
  }
That aside, have you ever felt the need to implement your own Win32 event, or SDL event, or X11 event, or epoll_event, or a custom DOM event or whatever?

If you're writing a good library, give the user the data they need, and let them handle it however they wish, don't force them int your framework.

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