How to kill a function in Swift 3?

Question

iOS

Hello!
The problem is simple, how to kill the running function?
I will describe the problem: the function is loading various videos, and if the download exceeds 15 seconds, I ask the user whether to continue or not.
If yes, continue loading, if not, kill the function. To stop loading and executing this function. How to implement it? Tell.

Answer 1

ActiveTask.cancel()

Answer 2

Here you should have some kind of asynchronous task that is executed in a separate thread using OperationQueueor GCD, you should have some one that will be Timercalled after 15 seconds and check this task

Answer 3

Make a cloner that will accept Bool and if everything is OK, then one code will be executed, and if not, then nothing will happen.