gdb: call accessor methods on NSManagedObject subclass?

Question

I have a class, Song, which subclasses NSManagedObject. I'm using GDB to try and figure out a problem I'm having, and am having a hard time calling an accessor on my class using gdb.

Song.h:

@property (nonatomic, retain) NSString * title;

Song.m:

@dynamic title;

In the debugger, I see the "title" field on the object, when I try to print the value using the accessor, which should be generated at runtime if I understand correctly, it gives me an error:

 (gdb) po aSong  <Song: 0x59188d0>
 (entity: Song; id: 0x59162d0
 <x-coredata://99BE63F8-840A-47B5-A259-BCD74E1811C4/Song/p2>
 ; data: {
     composers = "<relationship fault: 0x4d62f30 'composers'>";
     dateCreated = nil;
     songLists = "<relationship fault: 0x59243c0 'songLists'>";
     title = "cancel?"; })  
 (gdb) p aSong.title  There is no member named
 title.
 (gdb) p [aSong title]
 Target does not respond to this message selector.

Chances are I'm doing something really stupid here, but what am I doing wrong? Is there any way to introspect an object and see what messages it will respond to using GDB?

Answer 1

You can access dynamically generated properties in gdb using the valueForKey: method, as in [aSong valueForKey:@"title"]. (This technique works for synthesized properties too, if you're a masochist, but really it only comes in handy when inspecting NSManagedObject and its subclasses.)