Objective-C ARC: strong vs retain and weak vs assign

Question

There are two new memory management attributes for properties introduced by ARC, strong and weak.

Apart from copy, which is ob

Answer 1

The differences between strong and retain:

• In iOS4, strong is equal to retain
• It means that you own the object and keep it in the heap until don’t point to it anymore
• If you write retain it will automatically work just like strong

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The differences between weak and assign:

• A “weak” reference is a reference that you don’t retain and you keep it as long as someone else points to it strongly
• When the object is “deallocated”, the weak pointer is automatically set to nil
• A "assign" property attribute tells the compiler how to synthesize the property’s setter implementation