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An exemplar based Smalltalk

Authors:

Wilf R. LaLonde,

Dave A. Thomas,

John R. PughAuthors Info & Claims

OOPSLA '86: Conference proceedings on Object-oriented programming systems, languages and applications

Pages 322 - 330

https://doi.org/10.1145/28697.28729

Published: 01 June 1986 Publication History

Abstract

Two varieties of object-oriented systems exist: one based on classes as in Smalltalk and another based on exemplars (or prototypical objects) as in Act/1. By converting Smalltalk from a class based orientation to an exemplar base, independent instance hierarchies and class hierarchies can be provided. Decoupling the two hierarchies in this way enables the user's (logical) view of a data type to be separated from the implementer's (physical) view. It permits the instances of a class to have a representation totally different from the instances of a superclass. Additionally, it permits the notion of multiple representations to be provided without the need to introduce specialized classes for each representation. In the context of multiple inheritance, it leads to a novel view of inheritance (or-inheritance) that differentiates it from the more traditional multiple inheritance notions (and-inheritance). In general, we show that exemplar based systems are more powerful than class based systems. We also describe how an existing class based Smalltalk can be transformed into an exemplar-based Smalltalk and discuss possible approaches for the implementation of both and-inheritance and or-inheritance.

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Nørmark KThomsen LThomsen BWarth A(2012)Object-oriented programming with gradual abstractionProceedings of the 8th symposium on Dynamic languages10.1145/2384577.2384583(41-52)Online publication date: 22-Oct-2012
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Mallet FLagarde FAndré CGérard STerrier F(2009)An automated process for implementing multilevel domain modelsProceedings of the Second international conference on Software Language Engineering10.1007/978-3-642-12107-4_22(314-333)Online publication date: 5-Oct-2009
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Index Terms

An exemplar based Smalltalk
1. Human-centered computing
  1. Human computer interaction (HCI)
2. Software and its engineering
  1. Software notations and tools
    1. General programming languages
      1. Language types

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Published In

cover image ACM Conferences

OOPSLA '86: Conference proceedings on Object-oriented programming systems, languages and applications

June 1986

508 pages

ISBN:0897912047

DOI:10.1145/28697

Editor:
Norman Meyrowitz

ACM SIGPLAN Notices Volume 21, Issue 11
Proceedings of the 1986 conference on Object-oriented programming systems, languages, and applications
Nov. 1986
495 pages
ISSN:0362-1340
EISSN:1558-1160
DOI:10.1145/960112
Issue’s Table of Contents

Copyright © 1986 ACM.

Permission to make digital or hard copies of all or part of this work for personal or classroom use is granted without fee provided that copies are not made or distributed for profit or commercial advantage and that copies bear this notice and the full citation on the first page. Copyrights for components of this work owned by others than ACM must be honored. Abstracting with credit is permitted. To copy otherwise, or republish, to post on servers or to redistribute to lists, requires prior specific permission and/or a fee. Request permissions from [email protected]

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Published: 01 June 1986

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Nørmark KThomsen LThomsen BWarth A(2012)Object-oriented programming with gradual abstractionProceedings of the 8th symposium on Dynamic languages10.1145/2384577.2384583(41-52)Online publication date: 22-Oct-2012
https://dl.acm.org/doi/10.1145/2384577.2384583
Mallet FLagarde FAndré CGérard STerrier F(2009)An automated process for implementing multilevel domain modelsProceedings of the Second international conference on Software Language Engineering10.1007/978-3-642-12107-4_22(314-333)Online publication date: 5-Oct-2009
https://dl.acm.org/doi/10.1007/978-3-642-12107-4_22
Ungar DSmith RRyder BHailpern B(2007)SelfProceedings of the third ACM SIGPLAN conference on History of programming languages10.1145/1238844.1238853(9-1-9-50)Online publication date: 9-Jun-2007
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Cook W(2005)Object-oriented programming versus abstract data typesFoundations of Object-Oriented Languages10.1007/BFb0019443(151-178)Online publication date: 9-Jun-2005
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Evered MKeedy JSchmolitzky AMenger G(2005)How well do inheritance mechanisms support inheritance concepts?Modular Programming Languages10.1007/3-540-62599-2_44(252-266)Online publication date: 2-Jun-2005
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Foote BJohnson RNoble J(2005)Efficient multimethods in a single dispatch languageProceedings of the 19th European conference on Object-Oriented Programming10.1007/11531142_15(337-361)Online publication date: 25-Jul-2005
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