Question about classes and inheritance

This is a discussion on Question about classes and inheritance within the C++ Programming forums, part of the General Programming Boards category; Say I have a class Item which overloads the assignment operator if I make a class called weapon that publicly ...

  1. #1
    Registered User ~Kyo~'s Avatar
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    Question about classes and inheritance

    Say I have a class Item which overloads the assignment operator if I make a class called weapon that publicly inherits the Item class can I use the operator to assign a weapon to a item?
    like this?
    Code:
    Class Item
    {
       public:
          void SetAB(int, int);
          Item& operator = (const Item& i);
       private:
          int a;
          int b;
    };
    
    Item& Item::operator = (const Item& i)
    {
       a = i.a;
       b = i.b;
       return *this;
    }
    void Item::SetAB(int A,int B)
    {
       a = A;
       b = B;
    }
    
    Class Weapon : public Item
    {
       public:
       //doesnt matter i dont overload the = again
       private:
       int c;
       int d;
    };
    
    int main()
    {
       Weapon sword;
       sword.SetAB(1 , 2);
       Item temp;
       temp = sword;
       return 0;
    }
    Now my question is will temp.a and temp.b hold sword.a and sword.b and if I did it the other way sword = temp would sword hold temp.a and temp.b in sword.a and sword.b?

    Also is this something thats not violating any standards of programming? Like void main() or something i mean if it works but its just bad practace.

  2. #2
    VA National Guard The Brain's Avatar
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    It's easy.
    Last edited by The Brain; 10-23-2004 at 04:00 AM.
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  3. #3
    Code Goddess Prelude's Avatar
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    >can I use the operator to assign a weapon to a item?
    You can do this legally, but I really wouldn't recommend it as a good practice. What's wrong with writing an overloaded assignment operator for Weapon and doing things the conventional way?

    >Class Item
    >Class Weapon : public Item
    Case matters. The keyword is class, not Class.
    My best code is written with the delete key.

  4. #4
    Registered User ~Kyo~'s Avatar
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    Quote Originally Posted by Prelude
    >can I use the operator to assign a weapon to a item?
    You can do this legally, but I really wouldn't recommend it as a good practice. What's wrong with writing an overloaded assignment operator for Weapon and doing things the conventional way?

    >Class Item
    >Class Weapon : public Item
    Case matters. The keyword is class, not Class.
    I wrote that code not in the editor just off the top of my head so I didn't have any color coding.
    The main reason i dont overload it again is that I need to go from Item to weapon and weapon to Item or Item to Armor and Armor to Item.

    //longer version and background of program
    The reason i needed to do it is the inventory of my characters is an array of items but when they equip something like a weapon or armor i need to take the basic stuff like the ID and type etc just basic stuff when they equip the stuff it loads all the specifics from a file damage range defence for armor shield block rates etc. So instead of making some other function i was wondering if i could have a thing of class Item in a variable (player's hand) and when they equip it to what ever area could i just use = or would i need to write specalized functions to this. I wasnt as concerned about proper but more about would it generate unwanted results ie memory leaks or whatever. As I understand classes it should work since its going to be inherited but im not 100% sure that I wont generate leaks and have really bad things happen like running out of memory while people are playing on my server. Nor would I want the program to get confused and throw a save, and exit exception.

  5. #5
    Code Goddess Prelude's Avatar
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    >The main reason i dont overload it again is that I need to go from Item to weapon and
    >weapon to Item or Item to Armor and Armor to Item.
    So use pointers or references and polymorphism. That way you can use a pointer or reference to an Item and still have the full Armor or Weapon objects behind it. There's no good reason to allow slicing like that unless you know something that I don't (which is certainly possible).
    My best code is written with the delete key.

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