Ruby Object Model
- The S1 structure


An algebraic structure is described that forms the innermost core of the object model of the Ruby programming language. The structure, denoted S1, is induced by superclass and eigenclass links between objects. Since Ruby is a serious candidate for the most object-oriented programming language in the world, the S1 structure can be considered to be the core structure of object technology.

We provide a simple set-theoretic representation showing how the structure can be interpreted via set inclusion and set membership. We also describe lazy evaluation of infinite eigenclass chains. Finally, the Smalltalk precursor of the S1 structure is discussed.


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