MxGraph. Working with the Final Class in C++ Environment: C++ Introduction It is a common question, "Why shouldn't we inherit a class from STL classes?
" The answer to this question is simple—the Big Three rule [CLI95]. In other words, you should have a virtual destructor in a class if you want to make it a base class. However, there isn't any class in STL that defines a virtual destructor. Argouml.tigris.org. The Theory of Classification - A Course on OO Type Systems.