private void parseClassIntersection(PsiBuilder builder) {
    final PsiBuilder.Marker marker = builder.mark();

    boolean left = parseClassdef(builder);
    if (RegExpTT.ANDAND != builder.getTokenType()) {
      marker.drop();
      return;
    }
    while (RegExpTT.ANDAND == builder.getTokenType()) {
      builder.advanceLexer();
      final boolean right = parseClassdef(builder);
      if (!left && !right) {
        builder.error(RegExpBundle.message("parse.error.character.class.expected"));
      }
      left = right;
    }
    marker.done(RegExpElementTypes.INTERSECTION);
  }
private void parseClassIntersection(PsiBuilder builder)