bool ON_3dmRevisionHistory::IsEmpty() const { if ( 0 == m_revision_count && !CreateTimeIsSet() && !LastEditedTimeIsSet() && m_sCreatedBy.IsEmpty() && m_sLastEditedBy.IsEmpty() ) { return true; } return false; }
ON_BOOL32 ON_3dmRevisionHistory::IsValid() const { return ( LastEditedTimeIsSet() && ON_CompareRevisionHistoryTime(&m_create_time, &m_last_edit_time) <= 0 ); }