docs: protected <T extends AstNode> void printList(List<T> items,
                                                   StringBuilder sb) {
          int max = items.size();
          int count = 0;
          for (AstNode item : items) {
              sb.append(item.toSource(0));
              if (count++ < max-1) {
                  sb.append(", ");
              } else if (item instanceof EmptyExpression) {
                  sb.append(",");
              }
          }
      }