@Override
    public void visitRegExpBackref(RegExpBackref backref) {
      super.visitRegExpBackref(backref);
      if (mySupport != RegExpLanguageHost.Lookbehind.FULL) {
        stopAndReportError(backref, RegExpBundle.message("error.group.reference.not.allowed.inside.lookbehind"));
      }
    }
@Override
    public void visitRegExpBackref(RegExpBackref backref)