Building an interpreter for the rey programming language using desing patterns

Rey is an educational programming language. It is designed for students as their first programming language, so it contains a simple grammar and a user friendly environment. For ease of usage, an interpreter was chosen as the execution model. Most of the well-known industry interpreters are created with performance as a key point. Building an educational tool requires a different approach. Rather than performance, extensibility is the main goal of the Rey implementation. Unlike many others, the Rey interpreter is implemented in a high level programming language using design patterns. This paper describes the process of building a language interpreter using Interpreter, Factory Method and Visitor design patterns.