gistfile1.txt

// .h
NSView *_memberView;
@property (nonatomic,retain) IBOutlet NSView *memberView;

// .m
- (void)windowDidLoad {
  ...
  NSAssert( [self drawer], @"Drawer should not be nil!" );
  NSAssert( [self memberView], @"Member View should not be nil when we are setting it!" );
  [[self drawer] setContentView:[self memberView]];
  NSAssert( [[self drawer] contentView], @"Content View should not be nil when we just set it!" );
  ...
}

// output
*** Assertion failure in -[NFNetworkWindowController windowDidLoad]
Content View should not be nil when we just set it!