assertions over programs that otherwise are not annotated to receive these assertions. Varieties of AOP systems are characterized by which quantified assertions they allow, what they permit in the actions of the assertions (including how the actions interact with the base code), and what mechanisms they use to achieve the overall eftct. Here, we argue that all quantification is over dynamic events, and describe our preliminary work in developing a system that maps dynamic events to transformations over source code. We discuss possible applications of this system, particularly with respect to debugging concurrent systems.

Aspect-Oriented Programming (AOP) and related techniques propose solutions to the problem of crosscutting requirements, usually by providing a weaver that reimplements major parts of a compiler. This paper proposes XML based "operators" as an extensible aspect language. We work on XML representations of abstract syntax trees (AST) for the base language. These can be generated by modifying an existing compiler and allow us to use XML tools for tree query and manipulation. A prototype that encompasses constructs from several aspect languages, in particular AspectJ and Composition Filters, has been implemented.

this paper was presented at the 9th International Workshop on Foundations of ObjectOriented Languages, January 19, 2002

Abstract. Coming out from the process functional paradigm and using PFL – a process functional language, a generalized approach to weaving at the micro-structural level is presented. Exploiting the application of processes and PFL reflection property, we develop a generalized weaving scheme and we express it in the form of weaving pattern. Different specializations and extensions of weaving patterns occurring in aspect oriented languages are discussed. Weaving patterns expressed in terms of weaving chains provide us with the flexibility inevitable for the aspect oriented evolution of software systems instead of aspect oriented programming. Presented abstraction in the form of patterns comes out from integrating imperative, purely functional and object paradigms in the process functional paradigm and it may contribute to the application of aspect oriented approach to the area of automatic evolution of software systems.