docs: private void inFixup(VoltXMLElement inElement) {
          // make this an in expression
          inElement.name = "operation";
          inElement.attributes.put("optype", "in");
  
          VoltXMLElement rowElem = null;
          VoltXMLElement tableElem = null;
          VoltXMLElement subqueryElem = null;
          VoltXMLElement valueElem = null;
          for (VoltXMLElement child : inElement.children) {
              if (child.name.equals("row")) {
                  rowElem = child;
              }
              else if (child.name.equals("table")) {
                  tableElem = child;
              }
              else if (child.name.equals("tablesubquery")) {
                  subqueryElem = child;
              }
              else if (child.name.equals("value")) {
                  valueElem = child;
              }
          }
  
          VoltXMLElement inlist;
          if (tableElem != null) {
              // make the table expression an in-list
              inlist = new VoltXMLElement("vector");
              for (VoltXMLElement child : tableElem.children) {
                  assert(child.name.equals("row"));
                  assert(child.children.size() == 1);
                  inlist.children.addAll(child.children);
              }
          }
          else if (subqueryElem != null) {
              inlist = subqueryElem;
          }
          else {
              assert valueElem != null;
              inlist = valueElem;
          }
  
          assert(rowElem != null);
          assert(inlist != null);
          inElement.children.clear();
          // add the row
          inElement.children.add(rowElem);
          // add the inlist
          inElement.children.add(inlist);
      }