尝试保存到Core Data时应用程序崩溃

Question

当我尝试保存到核心数据时，我在我的应用中遇到了这个奇怪的错误。它曾经工作正常，直到我突然开始收到此错误：

$ awk '{gsub(/1 2|2 1/,"2 2")}1' file
A1      A1      0       0       1       1       0 0     0 0     2 2     2 2
A2      A2      0       0       1       1       1 1     1 1     0 0     2 2
A3      A3      0       0       1       2       1 1     1 1     0 0     2 2
A4      A4      0       0       1       1       1 1     0 0     0 0     2 2

我尝试放置一个异常断点，当我尝试执行时抛出它：

CoreData: error: Serious application error.  Exception was caught during Core Data 
change processing.  This is usually a bug within an observer of 
NSManagedObjectContextObjectsDidChangeNotification. Object's persistent store is 
not reachable from this NSManagedObjectContext's coordinator with userInfo (null)

我不确定为什么会这样，我甚至尝试重置模拟器，但我仍然遇到这个错误。任何想法??