             array += nativeTargets as [PBXObject]
             array += fileReferences as [PBXObject]
             array += projects as [PBXObject]
+            array += versionGroups as [PBXObject]
             return array
         }
         set {

    public var groups: [PBXGroup] = []
    public var fileElements: [PBXFileElement] = []
    public var configurationLists: [XCConfigurationList] = []
    public var buildConfigurations: [XCBuildConfiguration] = []
    public var variantGroups: [PBXVariantGroup] = []
    public var targetDependencies: [PBXTargetDependency] = []

        case let object as PBXNativeTarget: nativeTargets.append(object)
        case let object as PBXFileReference: fileReferences.append(object)
        case let object as PBXProject: projects.append(object)
        case let object as XCVersionGroup: versionGroups.append(object)
        default: break
        }
    }
