How can I throw compile-time BP error? (through c++)

[anonymous_user_f7e6301e]

I want to throw BP error in compile-time when specific property is null.
Is there any way to do through c++? (like overriding OnRegister, PostLoad, InitializeComponent…)

[Kiruse]

This would help to enforce particular rules and avoid user errors. I’d like to know this too.

[idbrii]

You need to create a custom K2Node.

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Call UK2Node::Message_Error and UK2Node::Message_Warn to output blueprint compile errors.

You can also create custom Pins on your K2Node to validate specific input types.

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Also have a look at FNodeHandlingFunctor.

[idbrii]

Related question about creating a K2Node: Custom Blueprint K2Node Creation: Node doesn't show up - Blueprint - Unreal Engine Forums