return constructor;
}
public XQExpression visit(AxisStep step, XQueryContext ctxt) throws XQueryException {
NodeTest nt = step.getNodeTest();
nt.visit(this, ctxt);
boolean isLoopInvariant = nt.isLoopInvariant();
if(isLoopInvariant) {
removeInvariants(nt);
return hookLoopInvariant(step);
}