Declarative Meta Programming for a Language Extensibility Mechanism

Today, many dialects of traditional programming languages exist [6]. In most cases, they add some programming paradigm or functionality to the original language. A major drawback of these dialects is that they have hard coded the extensions into the compiler. In an open mechanism, programmers may introduce extensions to the language to t their own development needs. Otherwise every extension requires a re-implementation of the language compiler, which is not a exible solution. It has already been demonstrated that meta programming is a solution to this problem [10, 11]. For example, OpenJava is an extensible dialect of Java where the meta programs specify a transformation from the extended language to the original language. These meta programs are normal Java programs that make use of the OpenJava MOP to inspect and modify the code. In such a system, a meta program that adds accessor methods to a class looks more or less like this (in pseudo-code):