protected void addExtern( Service service, Name name, Token language,
Token xname, Token xnameImport, Token serializer,
Token serializerImport ) throws ParseException
{
Map<String, Opt> opts = new HashMap<String, Opt>();
opts.put( "Extern."+language.image, new Extern( name, language, xname,
xnameImport, serializer, serializerImport ) );
service.addExtern( name, opts );
}