deque iterators

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C++

STL

I created a template class that has a deque object. I infrequently want to be able access the std::deque::iterator object. However, I have been unable to get a very simple example to work... Any ideas how to fix it?
I have an example working now using protected and private inheritance, but I would prefer layering for performance reasons and generality if my class has more than one deque/vector. Moreover, with layering, I had hide more implementation details...

1st try

template<typename T>
class XYZ {
std::deque<T> B;
....
public:
std::deque<T>::iterator begin() { return B.begin(); }
);

warning C4346: 'std::deque<Task>::iterator' : dependent name is not a type
error C2146: syntax error : missing ';' before identifier 'begin'

2nd try

template<typename T>
class XYZ {
std::deque<T> B;
....
public:
std::_Deque_iterator<T, std::allocator< std::deque<T> > > begin() { return B.begin(); }
};

Strange error message:

error C2440: 'initializing' : cannot convert from 'std::_Deque_iterator<_Ty,_Alloc>' to 'std::_Deque_iterator<_Ty,_Alloc>'