Building Parsers with Java™

13.12. Example Applications

You can combine facts, rules, and lists into logic programs that solve complex problems. Rules add much more power and complexity to a logic program than facts do. A program with ten rules may take an hour or more for a human reader to comprehend. A well-written logic program may be much harder to understand than a well-written Java program. In part, this is because most developers have more experience with procedural programming elements than with recursive programming. It may also be that recursive programming is simply harder to comprehend than procedural programming.

13.12.1. An Authorization Program

Here is a program that models privileges in a semiconductor fabrication facility:

 priv(jim, operate, sputter); ...