Generation of abstract programming interfaces from syntax definitions

This paper describes how an Abstract Programming Interface () and its implementation can be generated from the syntax definition of a data type. In particular we describe how a grammar (in ) can be used to generate a library of access functions that manipulate the parse trees of terms over this syntax. Application of this technique in the + Meta-Environment has resulted in the elimination of 47% of the handwritten code, thus greatly improving both maintainability of the tools and their flexibility with respect to changes in the parse tree format. Although the focus is on ATerms, the issues discussed and the techniques described are more generic and are relevant in related areas such as XML data-binding.