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    <p>Question 1: You mentioned inheritance. Since inherited objects often need more bytes of storage, they don't fit into the place of a base object. If you try to put them in, you get a base object instead. This is called object slicing.</p> <p>Question 2: Design first, before you write code. There are a bunch of possible solutions. For a start you can keep it in main(), but later you will be forced to make a class like <code>PackageContainer</code> for holding your objects.</p> <p>Question 3 + 4: You need a copy constructor, an assignment operator= and a destructor, when a class object owns dynamically allocated objects (the Rule of the Big Three). So a <code>PackageContainer</code> will probably need them. You create objects dynamically using <code>new Object(..)</code>. You are responsible for destroying them and for giving their memory back to the system immediately before your vector of pointers is destroyed: </p> <pre><code>for (size_t i = 0; i &lt; shipment.size(); ++i) { delete shipment[i]; } </code></pre> <p>Since working with naked pointers to dynamically allocated objects is not safe, consider using</p> <pre><code>std::vector&lt;tr1::shared_ptr&lt;Package&gt; &gt; shipment; </code></pre> <p>instead or </p> <pre><code>std::vector&lt;std::shared_ptr&lt;Package&gt; &gt; shipment; </code></pre> <p>if your compiler understands C++0x. The <code>shared_ptr</code> handles freeing memory for you: It implements the Rule of the Big Three for one object pointer. It should be used in production quality code.</p> <p>But try to get it right with naked pointers also. I think that's what your homework assignment is about. </p>
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    1. POVector of Object Pointers, general help and confusion
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    1. USRené Richter
    1. USRené Richter
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    1. COThanks. Maybe this is just a gap of knowledge of mine when it comes to classes/objects, but I'm not quite sure how my int main() would populate a vector defined in the class? Wouldn't I just create another vector for each object created then? Also, using my example, doesn't a class require all it's members to be passed to it for construction? For example, I'm passing name, weight, address, to create each object? How/why would I be passing to it from int main()? Should the vector maybe have public access within my class then? Thanks
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    2. CO@Staypuft: A class doesn't require to get constructor parameters for all members, but it should initialize all of them to guarantee a valid object state. When encapsulating data objects inside a class, to put information into them and to get it back you have to design accessor and modifier methods appropriate to what you want to express. So main() takes only objects of the highest abstraction level in your program. They send "messages" to each other to achieve your goal. Try to get a good book on C++ like Bruce Eckel's "Thinking in C++". If you are lucky, you can find some online.
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