Towards a logical foundation for XML Schema

This paper defines a logic in which to express constraints on W3C XML Schema components and relationships between components and XML infoset items, for use in a formal rewriting of the W3C XML Schema Recommendations. The logic is essentially a constraint language over path expressions, interpreted equally with respect to an Infoset graph or a schema component graph. By 'logic' I mean the traditional three-part story comprised of a sentential form, a model theory and an interpretation.