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3 min readFeb 28, 2026
Swift

How to Use Actors

Protect mutable state in concurrent code.

Steps

  1. Paste the code into a Swift file or playground.
  2. Run it once to verify the output.
  3. Adjust the inputs to match your use case.

Copy and paste

import Foundation

actor CounterActor {
    private var value = 0

    func increment() -> Int {
        value += 1
        return value
    }
}

Task {
    let counter = CounterActor()
    let value = await counter.increment()
    print(value)
}

Notes

  • Keep functions small and focused for reuse.
  • Prefer safe APIs like optionals and guards.