Oh yes, and triggers have an event registered to them, a pointer is returned that represents that registered event. Although the registered event pointer is useless, it is there. These are called event[/b] variables.
If you look in the API, you will see that each TriggerRegister native and function returns an event.
Also, keep in mind that the event types correspond to the natives. When registering a player unit event, you have to use a EVENT_PLAYER_UNIT var. For example, EVENT_PLAYER_UNIT_DEATH. They are all rather predictable.
EVENT_UNIT_DEATH - single unit
EVENT_PLAYER_UNIT_DEATH - any unit owned by the player
The native/function tells you which types of events can be registered to the trigger using it, like TriggerRegisterPlayerUnitEvent takes EVENT_PLAYER_UNIT vars.
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wasn't nominated because I'm generally hated across wc3c, th, and thw. I'm well known, but not well known in a good way ;p. You could say that I'm infamous.