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Is it necessary to use an escaping mechanism for closures passed as function arguments?

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Answer from AI

In Swift, closures are non-escaping by default, meaning they cannot be stored and called after the function they are passed to has returned. If a closure needs to be stored and called later (e.g., in an asynchronous callback), it must be marked as @escaping.

Example:

func performAsyncTask(completion: @escaping () -> Void) {
    DispatchQueue.global().async {
        // some work
        completion() // call closure later
    }
}

If the closure is used only within the function and not stored, @escaping is not needed.

Thus, the escaping mechanism is required only when the closure might be called after the function exits, which is common in asynchronous operations.