Thread: Design question (sort of)

  1. #1
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    Design question (sort of)

    Hello,

    Say I want to create a class, that is going to contain a vector of some other objects. My question is this: Do you want the vector to contain the actual objects, or do you want the vector to contain pointers to dynamically allocated objects.

    You can assume that there were be setters and getters for this vector, as well as functions to add and remove items.

    In Java this wouldn't be an issue, but in C++ I don't know how to go abou it. If I create a vector of objects, then I can return it using a const reference, so no extra expensive copies are going to happen. But then again having a vector of pointers might come in handy at some other kind of operation, which I can't think of right now.

    All comments are welcome. Thanks...

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    C++ Witch laserlight's Avatar
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    One thing that you might do is store base class pointers in the vector so as to use polymorphism via virtual function calls. But if you are not doing this, chances are you should keep things simple and just store the objects directly.

    Note that you can store smart shared pointers or even use a pointer container.
    Quote Originally Posted by Bjarne Stroustrup (2000-10-14)
    I get maybe two dozen requests for help with some sort of programming or design problem every day. Most have more sense than to send me hundreds of lines of code. If they do, I ask them to find the smallest example that exhibits the problem and send me that. Mostly, they then find the error themselves. "Finding the smallest program that demonstrates the error" is a powerful debugging tool.
    Look up a C++ Reference and learn How To Ask Questions The Smart Way

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    So if I want to make my code more extensible I should use pointers I suppose...?

    As for smart shared pointers or pointer containers, doesn't that make things more complicated?

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    C++ Witch laserlight's Avatar
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    Quote Originally Posted by crazyinlove
    As for smart shared pointers or pointer containers, doesn't that make things more complicated?
    Yes, but the complication is hidden by the interface. Furthermore, if you really do need to approximate the behaviour they provide, then it does not make things more complicated because things are already inherently complicated. In fact, it makes things simpler by simplifying through an interface and existing implementation.
    Quote Originally Posted by Bjarne Stroustrup (2000-10-14)
    I get maybe two dozen requests for help with some sort of programming or design problem every day. Most have more sense than to send me hundreds of lines of code. If they do, I ask them to find the smallest example that exhibits the problem and send me that. Mostly, they then find the error themselves. "Finding the smallest program that demonstrates the error" is a powerful debugging tool.
    Look up a C++ Reference and learn How To Ask Questions The Smart Way

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    OK good. I'll stick to vector of objects for this project, but i'll keep vector of pointers in mind for the future

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