Class question

This is a discussion on Class question within the C++ Programming forums, part of the General Programming Boards category; hi, I am working with simple classes. When setting a class for an animal I use this code: Code: animal ...

  1. #1
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    Class question

    hi,
    I am working with simple classes. When setting a class for an animal I use this code:

    Code:
    animal someName;
    someName.info();
    So basically this creates a new animal class by the name of someName. Here's my problem: What do I do if I want the class name to be a variable? For example I want to be able to make a few animal classes, and each class name would be going up by 1.

    (animals1, animals2, animals3)

    to do this the name would have to be a variable. I tried creating a new class by using a pointer but it did not work. If anyone can shed some light on this it would be apreciated.

    thanks

  2. #2
    and the hat of wrongness Salem's Avatar
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    You seem to be heading for
    Cat cat("Tom");
    Dog dog("Butch");
    Mouse mouse("Jerry");

    Where I think you really want is say
    Animal animals[3] = { "Tom", "Butch", "Jerry" };

    The class represents the attributes common to all the members of your class (eg a name), and then you create instances of that class with specific names.
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  3. #3
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    well the example is not what I'm realy trying to do. Basically I want to be able to create a class name by whatever input the user has given me.

  4. #4
    Sweet
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    You can't really do that with C++ nor would I see the reasoning behind why you would want to.
    Woop?

  5. #5
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    Code:
    animal someName;
    someName.info();
    So basically this creates a new animal class by the name of someName. Here's my problem: What do I do if I want the class name to be a variable?
    Those lines don't create a new animal class by the name of someName. They create an object called someName that is a member of the animal class.

    Also, a class name is not a variable--it's a type just like int, double, string, etc. are types.

  6. #6
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    Quote Originally Posted by Mr.Pink
    well the example is not what I'm realy trying to do. Basically I want to be able to create a class name by whatever input the user has given me.
    If I'm understanding this right, you want a factory class or function.

    The following is a very simplistic example with the problem that, whenever you create a new class of Animal, you have to modify the function;
    Code:
    std::auto_ptr<Animal> AnimalFactory(const std::string &type, const std::string &name)
    {
        std::auto_ptr<Animal> retval;
        if (type == "Cat")
            retval = new Cat(name);
        else if (type == "Dog")
            retval = new Dog(name);
        //  other known animals
        return retval;
    }

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