Templated USTRUCT?

Development Pipeline & Plugins Editor Scripting
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1

Is there any way to use templates/generics on USTRUCT objects (or even UCLASS)?

For example, something like the following:

USTRUCT(Blueprintable, Category = "Scripting|Remote Character|Attributes")
template<typename Type>
struct FRemoteCharacterSubAttribute
{
	GENERATED_USTRUCT_BODY();
public:
	FRemoteCharacterSubAttribute() {
		Name = FString(L"Unassigned");
		BaseCost = 0.0f;
	}

	UPROPERTY(BlueprintReadWrite, Category = "Scripting|Remote Character|Attributes")
	FString Name;
	UPROPERTY(BlueprintReadWrite, Category = "Scripting|Remote Character|Attributes")
	float BaseCost;
	UPROPERTY(BlueprintReadWrite, Category = "Scripting|Remote Character|Attributes")
	Type MinValue;
	UPROPERTY(BlueprintReadWrite, Category = "Scripting|Remote Character|Attributes")
	Type Value;
	UPROPERTY(BlueprintReadWrite, Category = "Scripting|Remote Character|Attributes")
	Type MaxValue;
};

… And then you would use it like:

USTRUCT(Blueprintable, Category = "Scripting|Remote Character|Attributes")
struct FRemoteCharacterAttributes
{
	GENERATED_USTRUCT_BODY();
public:
	FRemoteCharacterAttributes() {
		fMovement.Name = FString("Movement");
		fMovement.BaseCost = 10.0f;
		fMovement.MinValue = 50.0f;
		fMovement.MaxValue = 500.0f;
		fMovement.Value = fMovement.MinValue;
	}

	UPROPERTY(BlueprintReadWrite, Category = "Scripting|Remote Character|Attributes")
	FRemoteCharacterSubAttribute<float> fMovement;
};

Any way to make this happen?

2

Hi Michael,

Template USTRUCTs, UCLASSES, UFUNCTIONs. etc. are not supported in any form, and are unlikely to be.

Steve

3

Is there any change on the subject of templates ?
Or any way to generate ustructs ?

4

Any news on this front?

5 
template<typename T>
struct FTemplateStruct: public TSharedFromThis<FTemplateStruct> {

	TSubclassOf<T> Class;

	T* Object;

};

this is also not working, then the question, how to make sucha struct not to be cleared by garbage collector?

6

There is an error in your code from the C++ point of view.
You have incorrectly specified the type in TSharedFromThis.

This should work correctly

template<typename T>
struct FTemplateStruct: public TSharedFromThis<FTemplateStruct<T>> {

	TSubclassOf<T> Class;

	T* Object;
};

The topic starter has a different problem that still hasn’t been solved. Apparently, UBT does not support templates, so it cannot generate code related to reflection support for them.

P.S. I apologise for the necro post.

1 Like
7

So，if we can rigister reflection after creating template struct?
Reading sorce code “Range.h”,and you will find that all of Range are created by template,but they can use Property System. I dont know how they do it,and where they rigister reflection.
Is any idea?