Adding new elements in a DocBook way

allows further extensions in a same way as with the standard DocBook schema

default namespace = "http://docbook.org/ns/docbook"

include "docbook.rnc"

db.register.role.attribute = attribute role { text }

db.register.size.enumeration = "8" | "16" | "32" | "64"

db.register.size.attribute = 
  attribute size { db.register.size.enumeration }

db.register.attlist =
    db.register.role.attribute?
  & db.register.size.attribute?
  & db.common.attributes
  & db.common.linking.attributes

db.register =
  element register 
  {
     db.register.attlist,
     db._text
  }

db.programming.inlines |= db.register