A Calculus of Space, Time, and Causality: its Algebra, Geometry, Logic

The calculus formalises human intuition and common sense about space, time, and causality in the natural world. Its intention is to assist in the design and implementation of programs, of programming languages, and of interworking by tool chains that support rational program development. The theses of this paper are that Concurrent Kleene Algebra (CKA) is the algebra of programming, that the diagrams of the Unified Modeling Language provide its geometry, and that Unifying Theories of Program- ming (UTP) provides its logic. These theses are illustrated by a fomalisation of features of the first concurrent object-oriented language, Simula 67. Each level of the calculus is a conservative extension of its predecessor. We conclude the paper with an extended section on future research directions for developing and applying UTP, CKA, and our calculus, and on how we propose to implement our algebra, geometry, and logic

A Strategy for Compiling Classes, Inheritance, and Dynamic Binding

This paper presents a refinement strategy for the compilation of a subset of Java that includes classes, inheritance, dynamic binding, visibility control, and recursion. We tackle the problem of compiler correctness by reducing the task of compilation to that of program refinement. More specifically, refinement laws are used as compilation rules to reduce the source program to a normal form that models an interpreter running the target code. The compilation process is formalized within a single and uniform semantic framework, where translations or comparisons between semantics are avoided. Each compilation rule can be proved correct with respect to the algebraic laws of the language