(Behavioural) Design Patterns as Composition Operators

Design patterns are typically defined informally, albeit in a standard format, and have to be programmed by the software designer into each new application. Thus although patterns support solution reuse, in practice this does not translate into code reuse. In this paper we argue that to achieve code reuse, patterns should be defined and used in the context of software component models. We show how in such a model, behavioural patterns can be defined as composition operators which can be stored in a repository, alongside components, thus enabling code reuse.