A Simple Example

• Take a look at SpellT.h and SpellT.cpp
• I would like to extend a class that we don't have access to.
• In this case I want to create a DoubleSpell class.
  • It just doubles the inpact of the spell.
• THIS IS SOMETHING YOU CAN DO, but it is not the correct way to do things in the end.
  • This is for a case where we don't have access to source code for the class.
• Note, that the building of DoubleSpellT does not require SpellT to know anything about the DoubleSpellT
• DoubleSpellT does some strange things
  • The way it is implmeneted, the constructor, GetSpellName and AddEffect in the base class are hidden by the new functions.
  • If we could alter SpellT we could do something better
• We can still call the hidden functions
  • SpellT::function() to call the base class.
• Note in the spell test, UseSpell can take a double,
  • But it does not behave properly.
  • This is called slicing
  • "From the persepective of other code, an object belongs to its defined class as well as to any base classes."
  • "From the perspective of a derived class, all public and protected data members and methods from the base class are available."