Volker Haarslev, Michael Wessel
We demonstrate the object-oriented editor GenEd supporting the design of specifications for visual notations. Prominent features of GenEd are (1) it is generic, i.e. domain-specific syntax and semantics are specified by users; (2) built-in parser for actual drawings, driven by formal specifications; (3) reasoning capabilities about diagrams and their specification. GenEd's specification language is based on a fully formalized theory for describing visual notations.