Using Smalltalk as a Reflective Executable

Object-oriented meta-languages such as MOF or EMOF are often used to specify domain specific languages. However, these meta-languages lack the ability to describe behavior or operational semantics. Several approaches have used a subset of Java mixed with OCL as executable meta-languages. In this paper, we report our experience of using Smalltalk as an executable meta- language. We validated this approach in incrementally building over the last decade, Moose, a meta-described reengineering environment. The reflective capa- bilities of Smalltalk support a uniform way of letting the developer focus on his tasks while at the same time allowing him to meta-describe his domain model. The advantage of our approach is that the developer uses the same tools and en- vironment he uses for his regular tasks.