processing
  Shows how to parse a specific XML vocabulary, extract the data, and store
  it back to XML.

persistence
  Shows how to implement C++ classes that know how to persist themselves in
  XML.

inheritance
  Shows how to implement XML persistence for C++ classes that use inheritance.

roundtrip
  Shows how to "roundtrip" an XML document, that is, parse it and serialize
  it back to XML.

hybrid
  Shows how to implement hybrid, partially in-memory, partially streaming
  parsing and serialization.

performance
  Measures the performance of the parser.
