An Object-oriented Formal Notation: Executable Specifications in Clay = Una notación formal orientada a objetos : especificaciones ejecutables con Clay

Resumen

This thesis presents Clay, a stateless object-oriented formal notation. Clay is class-based, has a nominal type system that integrates algebraic types and inheritance, has equality, method overriding with Scandinavian semantics, dynamic binding, and a rather permissive overloading.

The type system of Clay is used to reject illegal specifications, and also to help guide the translation schemes that define the Clay semantics and the generation of executable prototypes.

Clay has a first-order semantics that gives an interpretation in first-order logic of the main object-oriented constructions: inheritance, defining classes by cases, overloading, dynamic binding and static equality. Furthermore, the use of the concrete syntax of an automatic theorem prover (Prover9/Mace4) has allowed mechanising both, the Clay's meta-theory and specifications. For example, some of the theorems about Clay in this thesis have been proved semi-automatically.

The thesis presents also a compilation scheme of Clay specifications into Prolog programs. Code can be generated from implicit specifications, even recursive ones, something hard to find in other tools. My implementation takes advantage of various logic programming techniques in order to achieve reasonable efficiency: constraints, constructive negation, Lloyd-Topor transforms, incremental deepening search, etc.

A Clay compiler is also contributed, a tool that goes beyond the mathematical presentation of the translations into first-order logic and the synthesis of logic programs. I have built a compiler that supports syntax analysis of modular Clay specifications, type checking, translation of Clay specifications into first-order theories in Prover9/Mace4, and synthesis of executable Prolog prototypes.