Graph transformation modules and their composition

Abstract

In this paper, we investigate the notion of transformation modules as a structuring principle for the specification of graph transformation systems which provide a collection of operations on graphs. Based on the notion of transformation units, a concept that allows to specify binary relations on graphs, a transformation module consists of a set of transformation units. To be able to distinguish between hidden and public operations, a module has an export interface. Moreover, there may be an import interface and a formal parameter. The import interface allows the use of transformation units which are known in the environment of a module. The formal parameter consists of formal parameter units which specify operations on graphs in a loose way. A formal parameter unit may be instantiated by an exported transformation unit of another module through module composition.