Development of human-friendly notation for XML-based languages

XML is a popular choice for development of domain-specific languages. In spite of its popularity, XML is a poor user interface and a lot of languages can be improved by introducing custom notation. This paper presents an approach for development of custom human-friendly notation for existing XML-based language together with a translator between the new notation and XML. This approach is based on explicit representation of language abstract syntax that can be decorated with mappings to both XML and the custom notation. The approach supports iterative design and development of the language concrete syntax, allowing its modification based on users feedback. Development process is demonstrated on a case study of language for definition of graphical user interface layout.