Generic Validation of Structural Content with Parametric Modules

Abstract

In this paper, we demonstrate a natural mapping from element types of XML to module expressions of ML-like programming languages. The mapping is inductive, and the definitions of common XML operations can be derived as the module expressions are constructed. We show how to derive, in a generic way, the validation function, which checks an XML document for conformance to the content model specified by its DTD (Document Type Definition). One can view the validation function as giving types to XML elements, and the validation procedure a pre-requirement for typeful XML programming in ML.