code: public static Node<PluralType> findChild(Struct<PluralType> parent, PluralType type) {
      for (Node<PluralType> n : parent.nodes()) {
        if (n.type() == type) {
          return n;
        }
      }
      return null;
    }
docs: Find a child node of a given type in a parent struct, or return null.