anchor.diff:          .where((xml.XmlNode node) => node is xml.XmlElement)
           .map((xml.XmlNode node) => node as xml.XmlElement)
           .forEach((xml.XmlElement navigationPointNode) {
  -      if (navigationPointNode.name.local.toLowerCase() == "navPoint") {
  +      if (navigationPointNode.name.local.toLowerCase() == "navpoint") {
           EpubNavigationPoint navigationPoint =
               readNavigationPoint(navigationPointNode);
           result.Points.add(navigationPoint);
  
positive.code:         case "class":
            result.Class = attributeValue;
            break;
          case "playOrder":
            result.PlayOrder = attributeValue;
            break;
        }
  
negative.code:               readNavigationLabel(navigationListChildNode);
            result.NavigationLabels.add(navigationLabel);
            break;
          case "navtarget":
            EpubNavigationTarget navigationTarget =
                readNavigationTarget(navigationListChildNode);
            result.NavigationTargets.add(navigationTarget);
  