// evaluated by virtue of a forwards reference
case ParameterSet.NOT_SUPPLIED:
if (isImplicitlyRequiredParam()) {
String name = "$" + getVariableQName().getDisplayName();
XPathException e = new XPathException("A value must be supplied for parameter "
+ name + " because " +
"the default value is not a valid instance of the required type");
e.setXPathContext(context);
e.setErrorCode("XTDE0610");
throw e;
} else if (isRequiredParam()) {
String name = "$" + getVariableQName().getDisplayName();
XPathException e = new XPathException("No value supplied for required parameter " + name);
e.setXPathContext(context);
e.setErrorCode("XTDE0700");
throw e;
}
context.setLocalVariable(getSlotNumber(), getSelectValue(context));
}
return null;