C++ How do you search all Actors?

What is the syntax to search Actors, by type or tag?

I’m spawning stuff in the level and want it to notify AI of its presence. In UE3 I would just search all Actors filtered on the actor class and call a function on each. How is this done in UE4?

I found what I was looking for in World.h and examples of its use in the ShooterGameInfo class.

GetWorld()->GetPawnIterator()