Abstract delta modelling

Article / Letter to editorLeiden Inst Advanced Computer Science

Abstract delta modeling : software product lines and beyond

To prevent a large software system from collapsing under its own complexity, its code needs to be well-structured. Ideally we want all code related to a certain feature to be grouped together __called feature modularization__ and code belonging to different features not to mix __ called separation of concerns. But many concerns are known as 'cross-cutting concerns'. By their very nature their implementation needs to be spread around the code base. The software engineering discipline that has the most to gain from those properties is Software Product Line Engineering. It is concerned with the development and maintenance of multiple software systems at the same time, each possessing a different (but often overlapping) set of features. This gives rise to an additional need: The code for a given feature must not only be separated and modular; it also needs to be composable and able to deal gracefully with the presence or absence of other features. This thesis presents Abstract Delta Modeling, a formal framework developed to achieve these goals in software. The thesis is a product of the European HATS project. It formalizes the techniques of delta modeling, the main approach to variability used by HATSAlgorithms and the Foundations of Software technolog

Program refactoring using functional aspects

A functional aspect is an aspect that has the semantics of a transformation; it is a function that maps a program to an advised program. Functional aspects are composed by function composition. In this paper, we explore functional aspects in the context of aspectoriented refactoring. We show that refactoring legacy applications using functional aspects is just as flexible and expressive as traditional aspects (functional aspects can be refactored in any order), while having a simpler semantics (aspect composition is just function composition), and causes fewer undesirable interactions between aspects (the number of potential interactions between functional aspects is half the number of potential interactions between traditional aspects). We analyze several aspect-oriented programs of different sizes to support our claims