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PODerived class stored in ptr_vector not being destructed
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  1. PODerived class stored in ptr_vector not being destructed
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    copied!<p>Was trying to find the best way to use ptr_vector to store, access and release objects, especially when the stored object is inherited from other (ptr_vector should not have any issues with object slicing). But when running the below program, surprisingly the derived class isn't being destructed. Anyone know why?</p> <pre><code>#include &lt;boost/ptr_container/ptr_vector.hpp&gt; #include &lt;iostream&gt; #include &lt;boost/ptr_container/ptr_map.hpp&gt; #include &lt;boost/foreach.hpp&gt; using namespace std; class A { public: int id; A() {cout&lt;&lt;"Constructed A()"&lt;&lt;endl;} A(int i):id(i) {cout&lt;&lt;"Constructed A"&lt;&lt;i&lt;&lt;endl;} ~A() {cout&lt;&lt;"* Destructed A"&lt;&lt;id&lt;&lt;endl;} }; class B:public A { public: int i; B() {cout&lt;&lt;"Constructed B"&lt;&lt;endl;} B(int ii):i(ii) {id=ii;cout&lt;&lt;"Constructed B"&lt;&lt;i&lt;&lt;endl;} ~B() {cout&lt;&lt;"* Destructed B"&lt;&lt;i&lt;&lt;endl;} }; class zoo { boost::ptr_vector&lt;A&gt; the_animals; public: void addAnimal(A* a) {the_animals.push_back( a );} void removeAnimal(int id) {the_animals.release(the_animals.begin()+id); } void removeOwnership(int id) {the_animals.release(the_animals.begin()+id).release();} }; int main() { zoo z; z.addAnimal( new B(0) ); //delete abc;z.addAnimal(abc);//doing this will cause heap corruption B* lion=new B(1); z.addAnimal(lion); z.removeOwnership(1); delete lion; z.removeAnimal(0); }//main </code></pre> <p>The output for the program is:</p> <pre><code>Constructed A() Constructed B0 Constructed A() Constructed B1 * Destructed B1 * Destructed A1 * Destructed A0 </code></pre> <p>Why isn't B0 being destructed? Did the object get sliced?</p>
 

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