ObjectOriented Programming: History, Multiple Inheritance

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Object-Oriented Programming History, Multiple
Inheritance

• Jesús A. Izaguirre

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History of OOP I

• SIMULA (Nygaard Dahl, Norway, 1962)
• Motivation Objects for simulation (e.g., traffic
  control, epidemiology, queues, etc.)
• Techniques classes, inheritance, RTTI, virtual
  functions, concurrency, garbage collection,
  polymorphism
• Smalltalk (Kay, Xerox Parc, 1972)
• Motivation graphical user interfaces for
  personal computers, prototyping
• Techniques virtual machine (like Pascal),
  message passing, everything is an object, IDE,
  class browser, design patterns

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History of OOP II

• CLOS
• Motivation OO Lisp for AI
• Techniques multiple inheritance, multi-methods
• Hybrid languages
• Objective C (Cox)
• Motivation Next computers
• Techniques Complete set of libraries
• C (Stroustrup)

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History of OOP III

• Eiffel (Meyer, 1988-2002)
• Motivation Object-Oriented Software Construction
• Techniques design by contract, constrained
  genericity, incremental compilation
• CORBA, COM, DCOM, .NET
• Motivation components in distributed
  environment, multi-language

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Multiple Inheritance I

• We have two types
• Structure inheritance from disjoint abstractions
  (e.g., Real and Integer derived from Numeric and
  Comparable)
• Facility inheritance, to use a set of related
  facilities (e.g., image processing library used
  by our windows)

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Multiple Inheritance II

• Name clashes
• A class that inherits different but identically
  named methods is invalid
• One can use renaming of the methods in the
  derived (inherited class)

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Multiple Inheritance III

• Repeated ancestors (Hw 8, ex. 7)
• In a repeated descendant, versions of a
  repeatedly inherited class member represent a
  single member
• Versions inherited under different names (through
  renaming) represent separate members
• Methods may be redefined, that is, their behavior
  changed

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References

• History
• N.A.B. Gray, Programming with Class, Ch. 2, John
  Wiley Sons Ltd, 1994,
• Multiple inheritance
• B. Meyer, Object-Oriented Software Construction,
  Ch. 15, 2e, Prentice-Hall, 1997
• B. Stroustrup, The C Programming Language, Ch.
  15, Third Ed., Addison Wesley, 1997
• H. Sutter, More Exceptional C, pp. 155-167,
  Addison Wesley, 2002