Two Kind of Inheritance

• Implementation Inheritance
  • [What:] Inherit inst. vars and method code.
  • [Goal:] Code reuse, code mixin.
• Interface Inheritance (or Subtyping)
  • [What:] Inherit method names and signatures.
  • [Goal:] Avoid redundunt declaration.
  • [Goal:] Basis for genericity (dynamic dispatch).
• Recent trends: separate Impl./Interface inheritance (e.g. Java).