Try doing name.#first
as FIRST and LAST are reserved words and need escaping: https://developer.apple.com/library/content/documentation/Cocoa/Conceptual/Predicates/Articles/pSyntax.html I just tried: NSComparisonPredicate *p = (NSComparisonPredicate *)[NSComparisonPredicate predicateWithFormat:@"name.#first == 'Aaron'"]; NSDictionary *myself = @{@"name": @{@"first" : @"Aaron", @"last" : @"Tuller"}}; NSDictionary *yourself = @{@"name": @{@"first" : @"Jens", @"last" : @"Alfke"}}; NSLog(@"%i", [p evaluateWithObject:myself]); NSLog(@"%i", [p evaluateWithObject:yourself]); works as expected. -aaron > On Jan 9, 2017, at 6:01 PM, Jens Alfke <j...@mooseyard.com> wrote: > > I’m writing code that walks through an NSPredicate and generates an alternate > form of query from it (similar to what CoreData and Realm do.) > > I’m seeing some very weird undocumented behavior when format strings are > compiled into NSPredicates, if the format string includes a key-path with a > property named “first” or “last”. The resulting predicate contains an > NSExpression of an undocumented type. > > - For example, “name.middle == ‘Bob’” compiles to what you’d expect; the LHS > of the ‘equals’ predicate is an expression of NSKeyPathExpressionType, with > key-path “name.middle”. > - But “name.first == ‘Bob’” results in an LHS that’s of > NSFunctionExpressionType, with a function selector “valueForKeyPath:”, and > even weirder, the expression’s argument is an expression with the > undocumented expressionType 11. I don’t know what that is supposed to mean, > except that its -description is “FIRST” (all caps). > > NSComparisonPredicate > predicateOperatorType = NSEqualToPredicateOperatorType > leftExpression = > NSKeyPathExpression > expressionType = NSFunctionExpressionType > function = “valueForKeyPath:” > operand = > NSKeyPathExpression > expressionType = NSKeyPathExpressionType > keyPath = “name” > operand = SELF > arguments = [ > NSSymbolicExpression > expressionType = 11 (?????) > ] > rightExpression = > NSExpression > expressionType = NSConstantValueExpressionType > constantValue = @“Bob” > > Is there something magic about the property name “first”? The only related > thing I’ve seen is that in predicate syntax arrays can be indexed with > “[FIRST]” or “[LAST]”, but that’s in an array subscript not a keypath… > > —Jens > _______________________________________________ > > Cocoa-dev mailing list (Cocoa-dev@lists.apple.com) > > Please do not post admin requests or moderator comments to the list. > Contact the moderators at cocoa-dev-admins(at)lists.apple.com > > Help/Unsubscribe/Update your Subscription: > https://lists.apple.com/mailman/options/cocoa-dev/mandelbaum%40mac.com > > This email sent to mandelb...@mac.com _______________________________________________ Cocoa-dev mailing list (Cocoa-dev@lists.apple.com) Please do not post admin requests or moderator comments to the list. Contact the moderators at cocoa-dev-admins(at)lists.apple.com Help/Unsubscribe/Update your Subscription: https://lists.apple.com/mailman/options/cocoa-dev/archive%40mail-archive.com This email sent to arch...@mail-archive.com
