What do these errors in the XCode Debugger Mean?

Question

I have 2 errors in XCode and am trying to figure out what they mean.

The 1st one:

2009-06-30 18:56:27.998 Spark[4584:10b] Error setting value for key path filterPredicate of object <NSArrayController: 0x1482c0>[entity: group, number of selected objects: 1] (from bound object <NSSearchField: 0x143f20> with object ID 1387 in Nib named MainMenu.nib): [<NSManagedObject 0x1d8170> valueForUndefinedKey:]: the entity group is not key value coding-compliant for the key keyPath.

The 2nd One:

2009-06-30 18:55:09.773 Spark[4552:10b] Stack: (
    2517123243,
    2530655803,
    2517122699,
    2517122762,
    2460660063,
    2460665405,
    2460666553,
    2460658608,
    2460656933,
    2506231425,
    2460658608,
    2460656933,
    2506235920,
    2506231206,
    2506463760,
    2506487015,
    2460658608,
    2460656933,
    2506207562,
    2506207014,
    2460658608,
    2460665405,
    2460666553,
    2460658608,
    2460656933,
    2506203090,
    2460658608,
    2460656933,
    2506200493,
    2506198904,
    2506197947,
    2506197753,
    2506196904,
    8232
)

What do they mean?

Answer 1

It would appear you've tried to filter based on a key called 'group' in an object that doesn't have a key called group.

The rest is a stack trace.

Answer 2

I see the first occurrence most often when i have bound a control to an IBOutlet via Interface Builder and then removed/renamed the IBOutlet in the underlying class. Check on the Connections tab for File's Owner in IB and see that there are not any odd connections that need to be cleaned up.

The second is the cryptic stack trace used on the Console when you hit an exception. It is actually a list of pointer addresses allowing you to trace the execution path. There is a ton you can do on the console once you get comfortable there. I got a great headstart on this (and MUCH MORE) on Cocoa With Love: http://cocoawithlove.com/2008/10/debugging-tips-for-objective-c.html

Good Luck!