This paper presents a reflective architecture and an implemented prototype that supports aspect oriented programming in Smalltalk. The aspects are metaobjects which are weaved dynamically and the composition is noninvasive, thus enhancing flexibility and transparency. 1 Introduction The main goal of aspect oriented programming is to offer methods and techniques that improve the design architecture of complex systems, by decomposing them into independent components. This does not differ from the goals of many other paradigms, except from the fact that it focuses on the problems that arise when the different properties of a system cross-cut its basic functionality. [Hrsch95] One difference in the proposals for supporting AOP resides in the way in which the cross-cutting aspects are "weaved" across the functional components of the system: if the weaving is static or dynamic, and if there is code transformation. Additionally, there are proposals of specific languages for the support...

Many Object-Oriented Programming Languages provide reflective features which may be used to control the interpretive mechanism of the language. Often, these features are defined with respect to a golden braid consisting of objects, classes and metaclasses. This paper describes the Smalltalk golden braid and generalize it for multiple inheritance. Multiple inheritance leads to choices between many different inheritance strategies. The reflective features of Smalltalk cannot affect the basic mechanisms of inheritance and so an arbitrary choice must be made for multiple inheritance. A language is described in which the reflective features of Smalltalk are extended so as to allow programmer defined inheritance strategies. 2 Introduction The evaluation of a programming language expression e in a given context c may be described by the evaluation of a program p which takes a representation of e and c as input. e is termed an object-level construct whilst p and the representations of e and ...