docs: public void free()
      {
          m_keyArea.removeKeyField(this);
          m_keyArea = null;
          m_field = null;
          if (m_fieldTempParam != null)
              m_fieldTempParam.free();
          m_fieldTempParam = null;        // BaseField
          if (m_fieldStartParam != null)
              m_fieldStartParam.free();
          m_fieldStartParam = null;   // BaseField
          if (m_fieldEndParam != null)
              m_fieldEndParam.free();
          m_fieldEndParam = null;         // BaseField
      }