Boost Python - Implementing a Cloning function

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Boost Python - Implementing a Cloning function

Jay Riley
I'm trying to implement a Cloning function for one of my classes I want to extend to Python. Extending the classes in C++ is easy as I can just override the Clone function, but it's definitely not working like that for Python. Here's the code, with unimportant detail ommitted.

    template<class T>
    class Cloneable
    {
    public:
        typedef boost::shared_ptr<T> ClonePtr;
        virtual ClonePtr Clone() = 0;
    };
   

    class Action : public Cloneable<Action>
    {
    public:
        virtual ClonePtr Clone() override;
    }

    Action::ClonePtr Action::Clone()
    {
        return ClonePtr(new Action(*this));
    }

    class Attack : public Action
    {
        public:
                   virtual ClonePtr Clone() override;
    }

    Attack::ClonePtr Attack::Clone()
    {
        return Attack::ClonePtr(new Attack(*this));
    }

    struct AttackWrapper : Game::Battles::Actions::Attack
    {
         Cloneable<Action>::ClonePtr AttackWrapper::Clone()
         {
               return call_method<Cloneable<Action>::ClonePtr>(self, "Clone");
         }
         Cloneable<Action>::ClonePtr AttackWrapper::CloneDefault()
         {
               return this->Action::Clone();
         }
    }

I expose it like follows:

    class_<Attack, boost::shared_ptr<Attack>, std::auto_ptr<AttackWrapper>,  bases<Action> >("Attack")
        .def(init<>())
        .def(init<Attack>())
        .def("Clone", &Attack::Clone, &AttackWrapper::CloneDefault)
        ;

In my python file:

    class ScriptedAttack(Attack):
        def __init__(self, Type, ID, Name, Flags, Power, MPCost = 0, SPCost = 0, Accuracy = 0.9, CritChance = 0.1, DefineOwnUse = False, EleWeights = None, StatusEffectChances = None):
              #initialization logic
        def Clone(self):
              #return ScriptedAttack(self)
              #what to put here?
    
    Fire = ScriptedAttack(ActionType.MagicAction, PrimaryEngine.GetUID(), "Fire", AttackFlags.Projectile | AttackFlags.Elemental, 32, 14, 0, 1.0, 0.1, False, {Elements.Fire: 1.0})
    Fire2 = Fire.Clone()
    ActLibrary.AddAttack(Fire)
    ActLibrary.AddAttack(Fire2)

I'm really not sure how to do this - I'm stuck on what I need to put under def Clone. I know I can't have multiple inits, and I can't define a copy constructor. I know about the copy function in python, but the Action class (base of Attack) has a custom copy constructor I need to be called.

Can someone help me out with how to do this?

Thanks in advance

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