A functor comprises a functor name and a list of arguments. The arguments are Nodes of any type except functor nodes (there is no functor nesting). Functors play three roles in rules - in heads they represent actions (procedural attachement); in bodies they represent builtin predicates; in TriplePatterns they represent embedded structured literals that are used to cache matched subgraphs such as restriction specifications.
All source code are property of their respective owners. Java is a trademark of Sun Microsystems, Inc and owned by ORACLE Inc. Contact coftware#gmail.com.