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Chair: Syd Bauman

Many shared XML vocabularies are built to be customized. Users are provided with a vocabulary, a grammar, and some documentation; various aspects of any or all of these may be modifiable by the user. Customization mechanisms often include methods to:

• narrow the schema components (removing elements or attributes)
• expand the schema components (adding new elements or attributes)
• loosen or restrict the schema (required versus optional, etc.)
• add to or change the semantics of a component
• document the customizations

Not all vocabularies provide all customization capabilities, and they frequently provide them via different mechanisms.

This symposium will examine various customization mechanisms and their ecosystems. How are structures added, subtracted, or changed? Are customization tools provided? Is there support for documenting customizations? Can a user know which customizations would “break” the tool or vocabulary? Can you easily compare a customization to the base vocabulary? To another customization?

Experts on several well-known XML markup vocabularies for textual documents will compare and contrast the customization mechanisms those provide, followed by an interactive session in which panelists answer questions on customization from the attendees. Languages will include: Akoma Ntoso, DITA, DocBook, JATS, and TEI.

There is nothing so practical as a good theory

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