MSVC++ compiler error C2143

Question

The following code excerpt is responsible for a cryptic MSVC++ compiler error:

template class Vec : public vector{
  public:
    Vec() :          


        

Answer 1

Try

template class Vec : public vector{
  public:
    Vec() : vector(){} // no 
    Vec(int s) : vector(s){} // same

    T& operator[](int i){return at(i);  }
    const T& operator[](int i)const{ return at(i);}
};

The constructor for a template class does not include the template signature in its name.

As a side note, your second constructor should really be

Vec(typename vector::size_type s) : vector(s){} // not necessarily int

Finally, you really shouldn't derive from vector, as it has a non-virtual destructor. Do not attempt to delete a Vec through a pointer to a vector.