Does UnsafePointer create a weak reference to the referenced object?

Using Swift
,
18

Expanding on using Unmanaged, you can write a wrapper that bundles up a Swift closure as your context object and executes it on the event loop, which will let you use normal closure capture rules with the C API:

extension EventLoop {
    func addTask(task: @escaping () -> Void) {
        class Context {
            let task: () -> Void
            
            init(task: @escaping () -> Void) {
                self.task = task
            }
        }
        
        let context = Context(task: task)
        
        EventLoopAddTask(self, Unmanaged.passRetained(context).toOpaque()) { ptr in
            let local = Unmanaged<Context>.fromOpaque(ptr!).takeRetainedValue()
            local.task()
        }
    }
}

You can use it with normal captures like this:

let name = "Jayson"
eventLoop.addTask {
    print("ran task with \(name) via Swift closure")
}

I uploaded a demo here:

(Don't judge the EventLoop implementation, I just wanted to quickly throw together a representative example)

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