docs: public void appendLine (@Nonnull final Line aLine)
    {
      if (m_aLineTail == null)
      {
        m_aLines = aLine;
        m_aLineTail = aLine;
      }
      else
      {
        aLine.m_bPrevEmpty = m_aLineTail.m_bIsEmpty;
        aLine.m_aPrevious = m_aLineTail;
        m_aLineTail.m_aNext = aLine;
        m_aLineTail = aLine;
      }
    }