code: public final JrsValueCursor iterateChildren() {
          JrsValue n = currentNode();
          if (n == null) throw new IllegalStateException("No current node");
          if (n.isArray()) { // false since we have already returned START_ARRAY
              return new ArrayCursor((JrsArray) n, this);
          }
          if (n.isObject()) {
              return new ObjectCursor((JrsObject) n, this);
          }
          throw new IllegalStateException("Current node of type "+n.getClass().getName());
      }
docs: Method called to create a new context for iterating all
  contents of the current structured value (JSON array or object)