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Gerenciamento de Memória em Swift - The Weak, the Strong, and the Unowned.
The document discusses Swift memory management and garbage collection. It covers automatic reference counting (ARC) which is Swift's default memory management system. ARC uses strong, weak, and unowned references to determine what objects to keep in memory. Reference counting tracks the number of references to an object and deallocates it from memory when the count reaches zero. The document also discusses issues like reference cycles, closures capturing values, and debugging memory management problems.
Gerenciamento de Memória em Swift - The Weak, the Strong, and the Unowned.
- 1. Txai Wieser Swift: Gerenciamentode Memória
- 2. Txai Wieser • Estudantede engenharia de computação na UFRGS. • Desenvolvedor iOS BallphyFityItWarrenRecolorindo o ReinoRepel
- 3. Swift: Gerenciamento deMemória
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- 9. Programador Garbage Collector AUTOMÁTICOMANUAL Gerenciadorde Memória (+)determinístico (-)trabalhoso (+)automático (-)afeta o runtime
- 10. Programador Garbage Collector AUTOMÁTICO Compilador MANUAL Gerenciadorde Memória ARC (+)determinístico (-)trabalhoso (+)automático (-)afeta o runtime
- 11. ARC Garbage Collector Tracinggarbage collection is a form of automatic memory management that consists of determining which objects should be deallocated by tracing which objects are reachable by a chain of references f r o m c e r t a i n “ r o o t ” objects, and considering the rest as “garbage” and collecting them. Reference counting is a technique of storing the n u m b e r o f r e f e r e n c e s , pointers, or handles to a resource such as an object, block of memory, disk space or other resource. It may a l s o r e f e r , m o r e specifically, to a garbage collection algorithm that uses these reference counts to deallocate objects which are no longer referenced.
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- 14. ref1 nil Automatic Reference Countingstrong 1 ref2
- 15. ref1 nil Automatic Reference Countingstrong 2 ref2
- 16. ref1 nil Automatic Reference Countingstrong 1 ref2
- 17. ref1 nil Automatic Reference Countingstrong 0 ref2
- 18. ref1 Automatic Reference Countingstrong ref2
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- 21. pessoa carro weakARC (VidaIndependente) 1 1
- 22. pessoa carro weakARC (VidaIndependente) 2 2
- 23. pessoa carro weakARC (VidaIndependente) 1 1 nil nil
- 24. pessoa carro weakARC (VidaIndependente) 1 1 nil nil ⚠
- 25. weakARC (Vida Independente) pessoacarro 1 2
- 26. weakARC (Vida Independente) pessoacarro nil nil 0 1
- 27. weakARC (Vida Independente) pessoacarro nil nil 0 nil
- 28. weakARC (Vida Independente) pessoacarro nil nil ✅
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- 43. Prevenção • Relações dePosse • NSTimer Cuidado Use logs: -(void)dealloc { NSLog(@"object is being deallocated"); } deinit { println("object is being deallocated") } • Closures • Referencias para classes • UIAlertController ⚠
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- 45. Value Types ReferenceTypes ✅ ⚠
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