return new StructuredQName("efx", "http://test/saxon/ext", "simple");
}
@Override
public ExtensionFunctionCall makeCallExpression() {
return new ExtensionFunctionCall() {
@Override
public Sequence call(XPathContext xPathContext, Sequence[] sequences) throws XPathException {
// get value of first arg passed to the function
Item arg1 = sequences[0].head();
String arg1Val = arg1.getStringValue();