How can I understand the data member 'Outer' in the UObjectBase class

Development Programming & Scripting C++
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Hello everyone,my question is simple,but confuse me very long.I always don’t konw the clear mean about the Outer member in the UObjectBase class.
In my view, if a member in class A named ‘m’ which is derived from UObject,so,I think the outer class of ‘m’ is A.
Is my understanding all right?
Can anybody tell me a exactly answer?
Thanks very much!

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An object’s “Outer” is the object which “owns” it. For instance, a Component is owned by its Actor or parent component, and Actors are owned by their Levels. Whenever you construct an object of a class derived from UObject, you provide it with an Outer. (CreateDefaultSubobject implicitly provides the current object as the Outer.)

Sometimes an object will have a pointer to some other object without owning that object. For instance, UNavMovementComponent has a pointer to its sibling UPathFollowingComponent. In that case, the UPathFollowingComponent will not have UNavMovementComponent as its Outer.

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Thanks !
You say An object’s “Outer” is the object which “owns” it. Can I understand the “owns” means relationship of the gameplay classes?
In the UE4 gameplay programing frame,I know actor is a container of component, Levels can have many actors,Map can have many levels. So,can I get to understand level’s outer is map?
Thanks!

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Generally it has that relationship, but not always. A ULevel’s outer is a UWorld (basically a map). But a child actor’s Outer is the Level, not the owning UChildActorComponent.

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Thanks very much for resolving my question.

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if I destroy an actor, which is the outer of a component, the component will also be destroyed?

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I believe it will be left without a parent so it will be garbage collected on the next iteration of the GC

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