How can method in Swift with inout parameter be used in Objective-C?

Question

I want

func foo(inout stop: Bool) -> Void {
    // ...
}

use in my Objective-C part. But it is never generated in Module-Swift.h header. If

Answer 1

You can't use an inout parameter when bridging with Objective-C, but you can do something similar if you use an UnsafeMutablePointer (T would be Bool in your case). It would look something like this:

@objc func foo(stop: UnsafeMutablePointer) -> Void {
    if stop != nil {
        // Use the .pointee property to get or set the actual value stop points to
        stop.pointee = true
    }
}

---

Example

TestClass.swift:

public class TestClass: NSObject {
    @objc func foo(stop: UnsafeMutablePointer) -> Void {
        stop.pointee = true
    }
}

Objective-C:

TestClass *test = [[TestClass alloc] init];
BOOL stop = false;
[test foo:&stop];
// stop is YES here