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Weak vs Unowned references

Updated May 6, 2026

Short answer

Both prevent retain cycles, but weak is optional and unowned is non-optional.

Deep explanation

weak becomes nil automatically; unowned assumes lifetime safety.

Real-world example

Delegates use weak references.

Common mistakes

  • Using unowned when object may deallocate.

Follow-up questions

  • When to prefer weak over unowned?
  • What is retain cycle?

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