Solving the TTC 2014 Movie Database Case with GrGen.NET

GRGEN.NET (www.grgen.net) is a programming language and development tool for graph structured data with pattern matching and rewriting at its core, which furthermore supports imperative and objectoriented programming, and features some traits of database-like query-result processing. Founded on a rich data modeling language with multiple inheritance on node and edge types, it offers pattern-based rewrite rules of very high expressiveness, with subpatterns and nested alternative, iterated, negative, and independent patterns, as well as preset input parameters and output def variables yielded to. The rules are orchestrated with a concise control language, which offers constructs that are simplifying backtracking searches and state space enumerations. Development is supported by graphical and stepwise debugging, as well as search plan explanation and profiling instrumentation for graph search steps – the former helps in first getting the programs correct, the latter in getting them fast thereafter. The tool was built for performance and scalability: its model data structures are designed for fast processing of typed graphs at modest memory consumption, while its optimizing compiler adapts the search process to the characteristics of the host graph at hand and removes overhead where it is not needed. GRGEN.NET lifts the abstraction level of graph-representation based tasks to declarative and elegant pattern-based rules, that allow to program with structural recursion and structure directed transformation [3]. The mission of GRGEN.NET is to offer the highest combined speed of development and execution available for graph-based tasks.