How can I properly document a method with a completion handler in iOS swift

Question

I'm documenting the code for my company's iOS application, and now I've moved on to methods that have a completion handler. Is there a specific method for documenting completion handlers, or should I just put it as part of the parameters?

for example:

/**
Description
- Parameters:
     - parameter1: description
     - parameter2: description
     - completion: description
*/

Is this the right way or is there another better way? Or maybe it should be in the "Returns" part of the documentation?

Thanks

Answer 1

Since the previous accepted answer failed to compile under Swift 3 (Function types cannot have argument label.) I would like to add an updated answer:

/**
Find User ID from Request
- Parameter from: The request containing relevant information.
- Parameter completionHandler: The callback called after retrieval.
- Parameter userId: The retrieved user id.
*/
static func extractUserId(from: RouterRequest, completionHandler: (_ userId: String) -> Void)

Result

Looks good enough for me!