How to capture a variable's current value for a block

Question

Is there a way to save the current value of a varible for later usage in a block?

For example, for this Playground code:

import UIKit
import XCPlayground         


        

Answer 1

You can bind an arbitrary expression to a named value in a capture list, the expression is evaluated when the closure is created. In your case you would bind self.i:

dispatch_after(dispatchTime, dispatch_get_main_queue(), { [i = self.i] in
    self.test(i)
})