210: Highlights

• Constructors, readers, and writers are called access functions. When you move references and assignments into access functions, you are practicing data abstraction.
• Data abstraction has many virtues, including the following:
  • Your programs become easier to reuse.
  • Your programs become easier to read.
  • You easily can augment what a class provides.
  • You easily can improve the way data are stored.
• If you anticipate that the detailed definition of a class may change, then you should provide access functions for the member variables to isolate the effects of the potential changes.