[maccard]

It's not that sort of header generation, it's a straight up code generator. You can write

    #include "MyClass.gen.h"

    UCLASS()
    class UMyClass : public UObject
    {
        GENERATED_BODY()

    public:

        UPROPERTY(BlueprintReadWrite, EditAnywhere )
        float MyFloat = 1.f;

        UPROPERTY()
        APlayerController* MyPc;
    };

in a header, and you get garbage collection, serialisation, script binding, editor UI out of the generated code.