private boolean parseAtom(PsiBuilder builder) {
    final PsiBuilder.Marker marker = parseGroup(builder);

    if (marker == null) {
      return false;
    }
    final PsiBuilder.Marker marker2 = marker.precede();

    if (parseQuantifier(builder)) {
      marker2.done(RegExpElementTypes.CLOSURE);
    }
    else {
      marker2.drop();
    }

    return true;
  }
private boolean parseAtom(PsiBuilder builder)