What is the difference betwee...

Here is the difference between NSMapTable and NSDictionary in Objective-C:

Key Differences

1. Weak References: NSMapTable allows you to use weak references for both keys and values, while NSDictionary only allows strong references.

2. Equality Comparison: NSMapTable allows you to specify custom equality comparison functions for keys, while NSDictionary uses isEqual: by default.

3. Hash Functions: NSMapTable allows you to specify custom hash functions for keys, while NSDictionary uses hash by default.

4. Concurrency: NSDictionary is toll-free bridged with CFDictionaryRef and is designed to be thread-safe, while NSMapTable is not.

5. Performance: NSDictionary is generally faster and more optimized than NSMapTable for most use cases.

When to Use NSMapTable

1. Weak References: If you need to store objects that may be deallocated, and you don't want to keep them alive, use N...