Question

I make a category like this:

@interface NSObject (defaultSelector)
+(NSString *) defaultSelector;
-(NSString *)defaultSelector;
@end

Then, I used it like this:

-(void)prefetchShortcutWithTable: (Class) someNSManagedObjectClass forInputArray: (NSArray *) inputArray withDictCache: (NSMutableDictionary *) dictToSave
{
    NSString * attribute = [someNSManagedObjectClass defaultSelector];
    [self prefetchShortcutWithTable:NSStringFromClass(someNSManagedObjectClass) forAttribute:attribute forInputArray:inputArray withDictCache:dictToSave];
}

The whole thing works. However, how does the compiler knows that someNSManagedObjectClass will be a subclass of an NSObject?

In fact, how do I rewrite the function so that -(void)prefetchShortcutWithTable: (Class) someNSManagedObjectClass forInputArray: (NSArray *) inputArray withDictCache: (NSMutableDictionary *) dictToSave only accept subclasses of NSManagedObject?

Answer 1

NSObject is the base class of any someNSManagedObjectClass or anyOtherClass you are going to make.