passing lambda causes error C2664: No user-defined-conversion operator available that can perform this conversion, or the operator cannot be called

Development Programming & Scripting C++
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1

I cannot pass a lambda to function
I tried TFunction& TFunctionRef but am getting the same error

void MyFunction(TFunctionRef<void(const float, const TArray<int32>&, Args&...)> func ){}

object.MyFunction([](const float dt,
		const TArray<int32>& obects,
		Position* p,
		Velocity* v){/*...*/});
2

Hmm what is Args in your function declaration ?

MyFunction must either be a template, or be located in a template struct/class like this

template<typename... Args>

Even then, the compiler doesn’t seem able to automatically infer the extra types so you’ll have to supply them :

template<typename... Types>
void MyFunction(TFunction<void(const float, const TArray<int32>&, Types&...)> func) {}

MyFunction<Position*, Velocity*>([](const float dt, const TArray<int32>& arr, Position* p, Velocity* v) {
    //...
});
3

its variadic params in template class as you said
the types are supplied with the class initialization

template<typename... Args>
class MyClass{}
-------------------------
MyClass<Position,Velocity >  object;

error C2664: 'void MyClass<Position,Velocity>::MyFunction(TFunction<void (float,const TArray<int32,FDefaultAllocator> &,Position &,Velocity &)>)': cannot convert argument 1 from 'AMyTestActor::BeginPlay::<lambda_fb06ae8b1ad5bbcb3d63bfe33c0b0665>' to 'TFunction<void (float,const TArray<int32,FDefaultAllocator> &,Position &,Velocity &)>'