An Algebraic Semantics of Uml Supporting Its Multiview Approach

We aim at using algebraic techniques, and in particular an extension, Casl-Ltl of the Casl basic language in order to produce a formal semantics of the UML. Contrary to most cases, this task is far from trivial. Indeed, the UML notation is complex, including a lot of heterogeneous notations for diierent aspects of a system, possibly described in diierent phases of the development process. Moreover, its informal description is incomplete and ambiguous , not only because it uses the natural language, but also because the UML allows the so called semantics variation points, that are constructs having a list of possible semantics , instead of just one.