Integrating a network-structured database into an object-oriented programming language

ABSTRACT

Smalltalk is an object-oriented language (Ingalls78, KayGoldberg77, Hewitt73). PIE is a subsystem that extends Smalltalk's descriptive power by supporting the creation, storage, retrieval and manipulation of network structures (GoldsteinBobrow80a,b,c; BobrowGoldstein80). These networks have been employed to represent software, documentation, electronic mail, calendars, people, addresses, bibliographic references and other items that together comprise the personal information space of a user of an office information system. By employing a common network representation, PIE supports an integrated environment for software development and office-related tasks. PIE has been developed collaboratively with Dan Bobrow, and is presently being used on an experimental basis by a small community at Xerox PARC. Smalltalk represents entities in the external world as objects. An object has a state—i.e. an assignment of values to a set of state variables—and a class. The class of an object defines the behavior of the object in terms of a set of methods. Thus the class is a generic description of a collection of objects, while the objects associated with a class provide a particular description of the state of individual instances.

REFERENCES

• 1: Bobrow, D.G. and Goldstein, I.P. "Representing Design Alternatives", Proceedings of the AISB Conference, Amsterdam, 1980.
• 2: Bobrow, D.G. and Winograd, T. "An overview of KRL, a knowledge representation language", Cognitive Science1, 1 1977.
• 3: Goldberg, A. and Robson, D. "A Metaphor for User Inteferace Design", Proceedings of the 13th Hawaii International Conference on System Science, Jan. 1979, pp. 148-157.
• 4: Ira P. Goldstein , Daniel G. Bobrow, Extending object oriented programming in Smalltalk, Proceedings of the 1980 ACM conference on LISP and functional programming, p.75-81, August 25-27, 1980, Stanford University, California, United States [doi>10.1145/800087.802792]
• 5: Goldstein, I.P. and Bobrow, D.G., "A Layered Approach to Software Design", Xerox PARC CSL-5-80, 1980b.
• 6: Goldstein, I.P. and Bobrow, D.G., "Descriptions for a Programming Environment", Proceedings of the First Annual Conference of the American Association for Artificial lntelligence, August, 1980c.
• 7: Hewitt, C., Bishop, P., and Steiger, R., "A Universal Modular ACTOR formalism for artificial intelligence", Proceedings of the Third International Joint Conference on Artificial Intelligence, 1973, pp. 235-245.
• 8: Daniel H. H. Ingalls, The Smalltalk-76 programming system design and implementation, Proceedings of the 5th ACM SIGACT-SIGPLAN symposium on Principles of programming languages, p.9-16, January 23-25, 1978, Tucson, Arizona [doi>10.1145/512760.512762]
• 9: Kay, A. and Goldberg, A. "Personal Dynamic Media" IEEE Computer, March, 1977.

INDEX TERMS

Primary Classification:
  D. Software
  D.1 PROGRAMMING TECHNIQUES
      D.1.5 Object-oriented Programming

Additional Classification:
  D. Software
  D.2 SOFTWARE ENGINEERING
      D.2.6 Programming Environments
          Subjects: Integrated environments
  D.3 PROGRAMMING LANGUAGES
      D.3.2 Language Classifications

          Nouns: Smalltalk

  H. Information Systems
  H.2 DATABASE MANAGEMENT
      H.2.1 Logical Design
          Subjects: Data models

General Terms:
Languages, Management