Question

I read another post that answered a question regarding iterators for vectors of pointers. I tried to use the same concept in my code but I receive some compilation errors. The code sample I was basing my code on is:

vector<c*> cvect;
cvect.push_back(new sc);
vector<c*>::iterator citer;
for(citer=cvect.begin(); citer != cvect.end(); citer++) {
    (*citer)->func();
}

I want to use a similar concept to create a deep copy constructor for a class that has two data members that are vectors of pointers to objects. My code is similar to this:

class MyContainer {
    vector<MyStuff*> vecOne;
    vector<MyStuff*> vecTwo;

 public:
    MyContainer(const MyContainer& other);
};

MyContainer::MyContainer(const MyContainer& other) {
    // copy vector one
    vector<MyStuff*>::iterator vec1_itr;
    for (vec1_itr = other.vecOne.begin(); vec1_itr != other.vecOne.end(); vec1_itr++) {
        vecOne.push_back(new MyStuff(vec1_itr));
    }

    // copy vector two
    vector<MyStuff*>::iterator vec2_itr;
    for (vec2_itr = other.vecTwo.begin(); vec2_itr != other.vecTwo.end(); vec2_itr++) {
        vecTwo.push_back(new MyStuff(vec2_itr));
    }
}

I get some compilation errors like:

/path/MyContainer.cpp:38: error: no match for ‘operator=‘ in ‘vec1_Itr = other->MyContainer::vecOne. std::vector<_Tp, _Alloc>::begin [with _Tp = MyStuff*, _Alloc = std::allocator<MyStuff*>]()‘

candidates are: __gnu_cxx::__normal_iterator<MyStuff*, std::vector<MyStuff, std::allocator<MyStuff> > >& __gnu_cxx::__normal_iterator<MyStuff*, std::vector<MyStuff, std::allocator<MyStuff> > >::operator=(const __gnu_cxx::__normal_iterator<MyStuff*, std::vector<MyStuff, std::allocator<MyStuff> > >&)

I also get an error for operator!=… And another set of the same errors for the other vector.

Answer 1

You forgot to dereference the iterators. Try this instead:

vecOne.push_back(new MyStuff( **vec1_itr ));

Edit 0:

Yes, should be double dereference (fixed above). And it should be the const_terator instead since you are dealing with const containing object:

vector<MyStuff*>::const_iterator vec1_itr;