Passing AActor reference into the nested object

Question

I want to do some logic of AActor in nested object and i need to pass this actor by reference to make it work. Unfortunatelly, i don't see a way how to pass "this" when "&" is used. Can someone explain me what's going on?

ATestActor.h

class UHelper;
UCLASS()
class PROJECT_API ATestActor : public AActor
{
    GENERATED_BODY()
    
public: 
    ATestActor();

protected:
    virtual void BeginPlay() override;

public: 
    virtual void Tick(float DeltaTime) override;

    UPROPERTY()
    UHelper* Helper;
};

UCLASS()
class PROJECT_API UHelper : public UObject
{
    GENERATED_BODY()

public:
    void Help(ATestActor* &TestActor)
    {
        // Do some stuff with testActor
    }
};

ATestActor.cpp

//other stuff

void ATestActor::BeginPlay()
{
    Super::BeginPlay();
    Helper = NewObject<UHelper>();
    
    //How can i pass "this" to the method?
    //Helper->Help(&this);//incorrect
}

Answer 1

&this creates a pointer to a pointer. your function Help accepts a reference to a pointer. calling Helper->Help(this); should work since this is already a pointer, then we pass the ptr by reference when calling Help.

edit:

actually i forgot this is a prvalue expression and prvalues cant bind to non const lvalue references.

you could do the following to get an lvalue of the this ptr.

auto* obj = this;
Helper->Help(obj);