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reference counting

Keeping a count of how many owners share a value and freeing it when the count reaches zero.

Rc keeps a strong count; Rc::clone increments it without copying the value, and dropping the last Rc frees the value. Arc is the atomic, thread-safe version.

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Examples

  • After let notes = Rc::clone(&theme);, Rc::strong_count(&theme) is 2; drop(notes) brings it back to 1.

See also

weak reference reference cycle smart pointer
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