The dynamic frames theory

The theory of Dynamic Frames has been invented to deal with the frame problem in the presence of encapsulation and pointers. It has proved more flexible and conceptually simpler than previous approaches that tackled the problem. It is now being actively used both for theoretical and for practical purposes related to the formal verification of program correctness. This paper presents the full theory of Dynamic Frames, together with its reasoning laws and exemplifies the use of these laws in proving correct several common design patterns. It also discusses the ongoing research on the topi

Pushouts in software architecture design

A classical approach to program derivation is to progressively extend a simple specification and then incrementally refine it to an implementation. We claim this approach is hard or impractical when reverse engineering legacy software architectures. We present a case study that shows optimizations and pushouts--in addition to refinements and extensions--are essential for practical stepwise development of complex software architectures.NSF CCF 0724979NSF CNS 0509338NSF CCF 0917167NSF DGE-1110007FCT SFRH/BD/47800/2008FCT UTAustin/CA/0056/200

State Based Encapsulation for Modular Reasoning about Behavior-Preserving Refactorings

Abstract. A properly encapsulated data representation can be revised for refactoring or other purposes without affecting the correctness of client programs and extensions of a class. But encapsulation is difficult to achieve in object-oriented programs owing to heap based structures and reentrant callbacks. This chapter shows that it is achieved by a discipline using assertions and auxiliary fields to manage invariants and transferrable ownership. The main result is representation independence: a rule for modular proof of equivalence of class implementations.