Hi Pavel,
Making a transition between two inner states is the equivalent of destructing the derived class portion of the object but leaving the base class portion intact and then constructing a different derived class object on top of the base class portion. This is of course not possible in C++ ....
It is sort of possible using placement constructors and destructors: - allocate enough of memory to hold largest derived object - construct derived object 1 - destruct derived object 1 but keep its base class data - construct derived object 2 on the same place and 'reuse' base class data
Hmm, how do you avoid that the base class constructor is called when you construct the derived object 2? Not that I have ever used placement new, but I can't recall having seen the possibility of not calling the base class constructor when you call a derived class constructor. Regards, Andreas