On the recognizability of arrow and graph languages

In: Graph Transformations : Proceedings of the 4th International Conference on Graph Transformation, ICGT 2008. - (Lecture Notes in Computer Science ; 5214)
Berlin [u.a.]: Springer (2008), S. 336-350
ISBN: 978-3-540-87404-1
Buchaufsatz / Kapitel / Fach: Informatik
In this paper we give a category-based characterization of recognizability. A recognizable subset of arrows is defined via a functor into the category of relations on sets, which can be seen as a straightforward generalization of a finite automaton. In the second part of the paper we apply the theory to graphs, and we show that our approach is a generalization of Courcelle's recognizable graph languages.