Atomic way to operate on integers in Swift. Inspired by Java's AtomicInteger

AtomicInteger.swift

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import Foundation

public final class AtomicInteger {
    
    private let lock = DispatchSemaphore(value: 1)
    private var _value: Int
    
    public init(value initialValue: Int = 0) {
        _value = initialValue
    }
    
    public var value: Int {
        get {
            lock.wait()
            defer { lock.signal() }
            return _value
        }
        set {
            lock.wait()
            defer { lock.signal() }
            _value = newValue
        }
    }
    
    public func decrementAndGet() -> Int {
        lock.wait()
        defer { lock.signal() }
        _value -= 1
        return _value
    }
    
    public func incrementAndGet() -> Int {
        lock.wait()
        defer { lock.signal() }
        _value += 1
        return _value
    }
}

It looks like line 56 needs to be _value as well, otherwise, it will deadlock.

@enozero You're correct. I'll fix it now. Thank you.

Thanks! Great work!

Thank you for the great work and for sharing this and especially without the nonsense about licensing. Big thumbs up !

This class really should be provided by Swift out of the box. What were/are they thinking ?