Bits and Pieces

• Final: 5/6 8:00 - 10:00
• Look at diamond.cpp quickly.
• Templated classes.
  • I built a History Class Template.
  • There are many optional things that you can do.
    • But you will need to re-read these when you get there.
• The Handle class
  • This is an outdated topic.
  • This has been replaced by smart pointers.
  • This is discussed in Stroustrup, C++ Programming Language, 3rd.
  • The idea is to
    • Store a pointer to an object.
    • And a reference count.
    • When the class is constructed set the reference count to 1
    • As it is copied increment the reference count.
    • As it is deleted, decrease the reference count.
    • When the reference count is 0, free the pointer.
  • Details:
    • The class actually keeps a pointer to an int.
    • This pointer is shared across all instances of the class.
  • The code is implemented here
• Friends
  • We briefly encountered friend functions before.
  • Declaring a function a "friend" of a class provides access to all members.
  • Gregorie warns us to be careful, this breaks the principles of encapsulation.
  • Meyers says don't do it.
  • I built an Example