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5.1: The Rules of the Model

  • Page ID
    36354
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    The Smalltalk object model is based on a set of simple rules that are applied uniformly. The rules are as follows:

    Rule 1. Everything is an object.

    Rule 2. Every object is an instance of a class.

    Rule 3. Every class has a superclass.

    Rule 4. Everything happens by message sends.

    Rule 5. Method lookup follows the inheritance chain.

    Let us look at each of these rules in some detail.


    This page titled 5.1: The Rules of the Model is shared under a CC BY-SA 3.0 license and was authored, remixed, and/or curated by Andrew P. Black, Stéphane Ducasse, Oscar Nierstrasz, Damien Pollet via source content that was edited to the style and standards of the LibreTexts platform; a detailed edit history is available upon request.