examples/ionic1/www/lib/ionic/js/ionic.bundle.js
function(newData) {
          var requiresRefresh = newData.length > 0 || newData.length < self.dataLength;

          self.dataLength = newData.length;

          return !!requiresRefresh;
        }
function(newData) {
          var requiresRefresh = newData.length > 0 || newData.length < self.dataLength;

          self.dataLength = newData.length;

          return !!requiresRefresh;
        }
function ( newData ) { var requiresRefresh = newData . length > 0 || newData . length < self . dataLength ; self . dataLength = newData . length ; return ! ! requiresRefresh ; }
A change in data only triggers a refresh if the data has length, or if the data's length is less than before.
A change in data only triggers a refresh if the data has length or if the data s length is less than before .