How to create a serial DispatchQueue in swift 3 with Xcode 8 beta 4?

Question

Created Aug ’16

Replies 4

Boosts 0

Views 21k

Participants 3

The following no longer works:

DispatchQueue(label: "Some Label", attributes: .serial)

The new DispatchQueue.Attributes does not contain a serial constant.

extension DispatchQueue {
    public struct Attributes : OptionSet {

        public let rawValue: UInt64

        public init(rawValue: UInt64)
        public static let concurrent: DispatchQueue.Attributes
        public static let initiallyInactive: DispatchQueue.Attributes

}

So how does one create a serial queue now?

Thanks!

Boost

Answer 1

jaguilar OP

Aug ’16

I'm guessing Dispatche Queues are created with a serial attribute by default?

// This creates a serial queue?
DispatchQueue(label: "com.my.label")

1

Answer 2

jshier OP

Aug ’16

That's the guess on swift-users: https://lists.swift.org/pipermail/swift-users/Week-of-Mon-20160801/002779.html

1

Answer 3

mattadatta OP

Aug ’16

Accepted Answer

Serial is the default. DispatchQueue.Attributes is an OptionSetType, but it doesn't make sense to include .serial as a member as [.serial, .concurrent] would make no sense. The abscence of the .concurrent attribute simply means it's serial 🙂

Source: https://github.com/apple/swift/pull/3927

2

Answer 4

jaguilar OP

Aug ’16

For reference, here's another post regarding this same question: https://forums.developer.apple.com/message/159457

Same guess as mine and the swift-users message.

0