How to use dispatch_queue_create in Swift 2.0?

Question

In swift 1.2, create a dispatch queue just like this:

dispatch_queue_create("imageProcessingQueue", DISPATCH_QUEUE_SERIAL)

But in swift 2.0, it has an error:

 Cannot invoke 'dispatch_queue_create' with an argument list of type '(String, dispatch_queue_attr_t!)'

dispatch_queue_create want an UnsafePointer<Int8> type, how can I get that.

Answer 1

I had this issue too, when assigning to a lazy var. I was able to bypass the error by explicitly adding a type to my variable:

lazy var myQueue: dispatch_queue_t = dispatch_queue_create("imageProcessingQueue", DISPATCH_QUEUE_SERIAL)

Answer 2

The error message is confusing. Most likely it originates from some code surrounding (most likely immediately preceding) this code.

To verify, create a new Playground and run this - it compiles without errors:

import Foundation
let queue = dispatch_queue_create("label", DISPATCH_QUEUE_SERIAL)