<classSpec ident="att.meterSigGrp.log" module="MEI.cmn" type="atts">
                        
                        <desc>Logical domain attributes.</desc>
                        
                        <attList org="group">
                           
                           <attDef ident="func" usage="req">
                              
                              <desc>Function of the meter signature group.</desc>
                              
                              <valList type="closed">
                                 
                                 <valItem ident="alternating">
                                    
                                    <desc>Meter signatures apply to alternating measures.</desc>
                                    </valItem>
                                 
                                 <valItem ident="interchanging">
                                    
                                    <desc>Meter signatures are interchangeable, e.g. 3/4 and 6/8.</desc>
                                    </valItem>
                                 
                                 <valItem ident="mixed">
                                    
                                    <desc>Meter signatures with different unit values are used to express a complex metrical
                                       pattern that is not expressible using traditional means, such as 2/4+1/8.</desc>
                                    </valItem>
                                 </valList>
                              </attDef>
                           </attList>
                        </classSpec>