Just to remember: various C++ tips

1. The assignment operator of a derived class must explicitly perform the assignment of it's base class

Derived& Derived::operator =(const Derived& aRhs){
  if( this != &aRhs ){
    Base::operator=(aRhs);
  }
  return *this;
}

2. Virtual destructor is vital for every polymorphic class because it's called when applying operator delete to the pointer of a base type pointing to the object of the derived type.
3. Never pass auto_ptr as reference.
4. Whenever a const auto_ptr is passed or returned as an argument, any attempt to assign a new object results in a compile-time error. With respect to constness, a const auto_prt behaves like a constant pointer (T* const p) not like a pointer that refers to constant (const T* p).
5. auto_ptr as memeber: implement the copy constructor and operator=. By default they transfer ownership.
6. Use const auto_ptr if member is to refer to the same object through all the lifetime.
7. To properly wrap class into Loki::SingletonHolder make the following members private:

• default constructor
• copy constructor
• operator=
• destructor
• operator&

8. If any constructor for a class is declared then the compiler won't generate the default one.