Abstract

It is becoming accepted that the Unified Modeling Language (UML) is not a single language, but a family of languages, that is expected to continue to grow and evolve, on a macro and a micro scale. The current, rather ad-hoc approach to defining UML has resulted in a semi-formal monolith, that hinders evolution of the language as well as the definition of new family members (profiles). It is also unsuitable as a basis for tool building. This talk will explore some of the issues surrounding the definition of a family of visual languages, drawing on UML for illustrative examples. Both syntactic and semantic issues will be discussed. The talk will conclude with an outline of an approach to engineering the definition of such languages using a small subset of a UML-like language, extended with richer mechanisms for managing packages.