NullProcessor.process(qc);
StringEscapesProcessor.process(qc);
Map<String, String> namespaces = NamespaceDeclProcessor.process(qc);
ProjectionProcessor.process(qc);
qc.jjtAccept(new ProjectionAliasProcessor(), null);
qc.jjtAccept(new AnonymousVarGenerator(), null);
// TODO: check use of unbound variables?
TupleExpr tupleExpr = QueryModelBuilder.buildQueryModel(qc, new ValueFactoryImpl());