This example shows how to use XML Schema polymorphism features
such as xsi:type attribute and substitution groups in the
C++/Tree mapping.

The example consist of the following files:

schema.xsd
  XML Schema which describes "men and supermen" instance documents.

instance.xml
  Sample XML instance document.

schema.hxx
schema.cxx
  Data types that represent the given vocabulary, a set of parsing
  functions that convert XML instance documents to a tree-like in-memory
  data structure, and a set of serialization functions that convert the
  in-memory representation back to XML. These are generated by xsd from
  schema.xsd. Note the use of --generate-polymorphic command line option.

driver.cxx
  Driver for the example. It first calls one of the parsing functions
  that constructs the in-memory representation from the input file. It
  then prints the content of the in-memory representation to STDERR.
  Finally, the driver serializes the in-memory representation back to
  XML.

To run the example on the sample XML instance document simply execute:

$ ./driver instance.xml
