No value will be returned by reference?

Development Pipeline & Plugins Editor Scripting
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I’m not sure if the OP was doing this in Blueprints or C++, but I ran in to this issue creating a custom event in C++, so I thought I’d post the solution here in case it helps.

I was trying to create a custom event that would pass an array of the currently selected actors whenever the selection changes. This was the signature in my original attempt:

DECLARE_DYNAMIC_MULTICAST_DELEGATE_OneParam(FOnSelectionChanged, TArray<AActor*> , SelectedObjects);

This caused the “NOTE” message which said “No Value will be returned by reference.”.

I solved it by looking for places in the Engine Source that used this same pattern with Arrays as the parameter type and found several examples. The solution was to use this signature:

DECLARE_DYNAMIC_MULTICAST_DELEGATE_OneParam(FOnSelectionChanged, const TArray<AActor*> &, SelectedObjects);

Notice it changes:

TArray<AActor*>

To

const TArray<AActor*> &

i.e. A const reference. After doing this (and deleting my plugin binaries and intermediate folders), the NOTE message was no longer present.

I hope this helps someone.

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