Compilation Strategies as Objects

In this paper we present an overview of the metaobject protocol approach to compilation. We take the position that object orientation in a compiler can be put to effective use in opening up the compiler for modification by the user. Interestingly, the natural scopes of effect of user intervention don't respect syntactic boundaries, so we require objects that are not just elements of the abstract syntax tree. We introduce a new kind of intermediate object for the process of compilation so that user modification of compilation strategies can be carried out in a coherent manner. We give some examples of user customizations, and outline the architecture of our Scheme compiler based on these principles