Moving from a vector with one allocator to a vector with another

Question

I've got a vector<T, alloc> where alloc is a simple wrapper on std::allocator<T> that performs some additional bookkeeping, like counting the number of created objects and such.

Now I want to move from my vector<T, alloc> into vector<T>. None of the vector move functions seems to accept vectors with different allocators.

How can I move data from one vector to another where the allocators are not the same?

Answer 1

As John Zwinck explains in his answer, you can not move the vector. However, you can move the elements of the vector as follows:

vector<...> u;
...
vector<...> v(
    std::make_move_iterator(u.begin()),
    std::make_move_iterator(u.end())
);

or

vector<...> u;
vector<...> v;
...
v.insert(
    v.end(),
    std::make_move_iterator(u.begin()),
    std::make_move_iterator(u.end())
);

or (suggested by Oktalist)

vector<...> u;
vector<...> v;
...
std::move(u.begin(), u.end(), std::back_inserter(v));