ISO/IEC 19757-4 NVDL (Namespace-based Validation Dispatching Language)

This is a home for user information related to the International Standard for document model validation of instances with multiple namespaces using different document models. NVDL is Part 4 of ISO/IEC 19757 DSDL (Document Schema Definition Languages)

Specification document (from the ISO/IEC page of Freely Available Standards):

Schemas for NVDL scripts

Note: As shown in the proposed technical corrigenda, the xml:lang= attribute of <message> elements is made optional

Tutorials for NVDL

Sourceforge project for the development of tutorials and test suites:

Public demonstrations available on the web:


Specifications utilizing NVDL

NVDL is the successor of NRL. There are some interesting use cases in James Clark's Namespace Routing Language (NRL) introduction at