[Int](courses.keys) 这种写法怎么会报错了?Array(courses.keys)是可以的,xcode版本6.3.2 难道是swift 1.2版本这种写法不行了?
cannot find an initializer for type '[(Int)]' that accepts an argument list of type '(LazyForwardCollection<MapCollectionView<Dictionary<String, String>, String>>)'