Re: The C++ Language 4th edition - Subclassing vector for range checking.

I was under the impression that it was generally a bad idea to subclass vector because the destructor is not virtual because if someone referenced an object of your class with a pointer and then deleted it with the base, the operation is undefined.

In The C++ Programing Language 4.4.1.2 Stroustrup says "... I often use a simple range-checking adaption of vector:"

template<typename T>
class Vec : public std::vector<T> {
public:
     using vector<T>::vector;

     T & operator[](int i)
         {return vector<T>::at(i);}

     const T & operator[](int i) const
          {return vector<T>::at(i);}
};

I thought this was some what dangerous because if an user of the class (Maybe not the person who wrote it) writes:
Vector<T> * vectorObject = new Vec<int>(100);
delete vectorObject;

Results in undefined behavior.

Did something change in C++11? Is there some common idiom where people create classes that must be on the stack or they should know not to delete the base?

I ask because this seems like it would create error prone code.