@Override
  public ASTNode findChildByRole(int role) {
    LOG.assertTrue(ChildRole.isUnique(role));
    switch(role){
      case ChildRole.STATEMENT:
        return PsiImplUtil.findStatementChild(this);

      case ChildRole.COLON:
        return findChildByType(COLON);

      case ChildRole.LABEL_NAME:
        return getFirstChildNode();

      default:
        return null;
    }
  }
@Override
  public ASTNode findChildByRole(int role)