@Nullable
  public static IElementType parseOption(final PrattBuilder builder, int rightPriority) {
    final MutableMarker marker = builder.mark();
    final IElementType type = builder.createChildBuilder(rightPriority).parse();
    if (type == null) {
      marker.rollback();
    } else {
      marker.finish();
    }
    return type;
  }
@Nullable
  public static IElementType parseOption(final PrattBuilder builder, int rightPriority)