This example shows how to use XML Schema polymorphism features such as
xsi:type attribute and substitution groups in the C++/Parser mapping.
The case when xsi:type is used on root elements is covered in the
polyroot examples.

The example consists of the following files:

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

instance.xml
  Sample XML instance document.

schema-pskel.hxx
schema-pskel.cxx
  Parser skeletons generated by the XSD compiler from schema.xsd.
  Note the use of the --generate-polymorphic command line option.

schema-pimpl.hxx
schema-pimpl.cxx
  Parser implementations that print the XML data to STDOUT.

driver.cxx
  Driver for the example. It first constructs a parser instance from
  all the individual parsers found in schema-pimpl.hxx. In then invokes
  this parser instance to parse the input file.

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

$ ./driver instance.xml
