Domain models are NOT aspect free

In proceedings of MoDELS/UML 2005, Steimann argues that domain models are aspect free. Steimann's hypothesis is that the notion of aspect in aspect-oriented software development (AOSD) is a meta-level concept. He concludes that aspects are technical concepts, i.e., a property of programming and not a means to reason about domain concepts in a modular fashion. In this paper we argue otherwise. We highlight that, by ignoring the body of work on Early Aspects, Steimann in fact ignores the problem domain itself. Early Aspects techniques support improved modular and compositional reasoning about the problem domain. Using concrete examples we argue that domain models do indeed have aspects which need first-class support for such reasoning. Steimann's argument is based on treating quantification and obliviousness as fundamental properties of AOSD. Using concrete application studies we challenge this basis and argue that abstraction, modularity and composability are much more fundamental.