Towards a Notion of Transaction in Graph Rewriting 1

We define transactional graph transformation systems (t-gtss), a mild extension of the ordinary framework for the double-pushout approach to graph transformation, which allows to model transactional activities. Generalising the work on zero-safe nets, the new graphical formalism is based on a typing discipline which induces a distinction between stable and unstable items. A transaction is then a suitably defined minimal computation which starts and ends in stable states. After providing the basics of t-gtss, we illustrate the expected results, needed to bring the theory to full maturity, and some possible future developments.