On Language Processors and Software Maintenance

This work investigates declarative transformation tools in the context of software maintenance. Besides maintenance of the language specification, evolution of a software language requires the adaptation of the software written in that language as well as the adaptation of the software that transforms software written in the evolving language. This co-evolution is studied to derive automatic adaptations of artefacts from adaptations of the language specification. Furthermore, AOP for Prolog is introduced to improve maintainability of language specifications and derived tools.Die Arbeit unterstützt deklarative Transformationswerkzeuge im Kontext der Softwarewartung. Neben der Wartung der Sprachbeschreibung erfordert die Evolution einer Sprache sowohl die Anpassung der Software, die in dieser Sprache geschrieben ist als auch die Anpassung der Software, die diese Software transformiert. Diese Koevolution wird untersucht, um automatische Anpassungen von Artefakten von Anpassungen der Sprachbeschreibungen abzuleiten. Weiterhin wird AOP für Prolog eingeführt, um die Wartbarkeit von Sprachbeschreibungen und den daraus abgeleiteten Werkzeugen zu erhöhen

Roles of Program Extension

. A formal and effective approach to the extension of the computational behaviour of logic programs is presented. The approach builds upon the following concepts. The extension of computational behaviour is modelled by semantics-preserving program transformations. Several basic roles involved in such transformations are identified. Every transformation defined solely in terms of the basic roles will be semanticspreserving by definition. Functional meta-programs on logic object programs are used to specify the basic roles and to derive programming techniques in the style of stepwise enhancement. Thus, the process of extending the computational behaviour of logic programs is regarded as disciplined meta-programming. 1 Introduction This paper is about adding functionality to declarative programs. We present a rigorous approach which relies on program transformation concepts and metaprogramming technology. Transformations are used to model the enhancement of programs, i.e., the..