Evaluate CoreData entity type in predicate

Question

I have a block predicate that I carefully crafted only to discover you can't use them in Core Data.

NSPredicate *rootContactPredicate = [NSPredicate predicateWithBlock:^BOOL(id evaluatedObject, NSDictionary *bindings) {

        BOOL isPersonAndRoot = ([[[evaluatedObject entity] name] isEqualToString:@"Person"] && [[(Person*)evaluatedObject accounts] count] == 0);
        BOOL isAccountAndRoot = ([[[evaluatedObject entity] name] isEqualToString:@"Account"] && [(Account*)evaluatedObject root] == nil);

        return isPersonAndRoot || isAccountAndRoot;
    }];

So I need to convert this into a standard String format predicate, but I am unclear on how to check the entity type for the evaluated object. The Person and Account entities are subclasses of a Contact entity which is the type being evaluated in the fetch request. I'm hoping it will see the sub-types.

Answer 1

Check the entity like this:

[NSPredicate predicateWithFormat:@"self.entity = %@", Person.entity];

Answer 2

Swift 4.0 way of checking for entity type using the entity property of the NSManagedObject as per malhal's suggestion.

let entityDescription = NSEntityDescription.entity(forEntityName: "Account", in: managedObjectContext)!
return NSPredicate(format: "entity = %@", entityDescription)