@Override
  @Nullable
  public String getFileReference() {
    final ASTNode element = getNode().findChildByType(RncTokenTypes.LITERAL);
    if (element == null) return null;
    final String s = EscapeUtil.unescapeText(element);
    return s.substring(1, s.length() - 1);
  }
@Override
  @Nullable
  public String getFileReference()