From Macros to Reusable Generative Programming

Generative programming is widely used both to develop new programming languages and to extend existing ones with domain-speci c sub-languages. This paper describes McMicMac, a framework for generative programming. McMicMac uses tree-transforming macros as language speci cations, and enhances them with inherited and synthesized attributes. The enhanced transformers can describe general compilation tasks. Families of these speci cations are grouped into mixin-like collections called vocabularies. Programmers can de ne new languages by composing these vocabularies. We have implemented McMicMac for Scheme and used it to build several systems, including the DrScheme programming environment. The principles of McMicMac carry over to other languages and environments.