internal override void AddDirective (string directive, IDictionary atts)
{
if (String.Compare (directive, "application", true, Helpers.InvariantCulture) != 0 &&
String.Compare (directive, "Import", true, Helpers.InvariantCulture) != 0 &&
String.Compare (directive, "Assembly", true, Helpers.InvariantCulture) != 0)
ThrowParseException ("Invalid directive: " + directive);
base.AddDirective (directive, atts);
}