gistfile1.txt

#import "AppDelegate.h"
#import <objc/runtime.h>

static NSString *Key = @"Key";

@interface A : NSObject
@property (strong, nonatomic) NSString *property;
@end

@implementation A

- (id)init
{
    if (self = [super init]) {
        self.property = @"Live Hard, Crash Harder.";
    }
    return self;
}

- (void)dealloc
{
    NSLog(@"Dealloc a. property is: %@", self.property);
}

@end

@interface B : NSObject
@property (weak, nonatomic) A *weakA;
@property (assign, nonatomic) A *unsafeA;
@end

@implementation B

- (void)dealloc
{
    NSLog(@"Dealloc b. Weak a: %@, unsafe a: %@, unsafe a's property: %@, unsafe a's class: %@", self.weakA, self.unsafeA, self.unsafeA.property, self.unsafeA.class);
}

@end

@implementation AppDelegate

- (BOOL)application:(UIApplication *)application didFinishLaunchingWithOptions:(NSDictionary *)launchOptions
{
    A *a = [[A alloc] init];
    B *b = [[B alloc] init];

    b.weakA = a;
    b.unsafeA = a;
    objc_setAssociatedObject(a, &Key, b, OBJC_ASSOCIATION_RETAIN);
    

    NSLog(@"Releasing b");
    b = nil;

    NSLog(@"Releasing a");
    a = nil;
    
    NSLog(@"Done");
    
    // Prints the following:
    //
    // Releasing b
    // Releasing a
    // Dealloc a. property is: Live Hard, Crash Harder.
    // Dealloc b. Weak a: (null), unsafe a: <A: 0x7f8513d13fc0>, unsafe a's property: (null), unsafe a's class: A
    // Done
    
    return YES;
}

@end