xcode - cannot find an initializer for type 'String' that accepts an argument list of type '(format: String, argument: UInt32

Question

I created a playground in Xcode 6.3 (6D570) and input these following code:

import UIKit
var randum_num = arc4random_uniform(13) + 1
String(format: "card%i", arguments: randum_num)

And I got this error:

cannot find an initializer for type 'String' that accepts an argument list of type '(format: String, argument: UInt32

Sorry I'm complete new in Swift, thanks for any advices!

P.S. I'm following this tutorial: link

Answer 1

You just have to omit "arguments:". Try like this:

let randum_num = arc4random_uniform(13) + 1
String(format: "card%i",  randum_num)

or simply

String(format: "card%i",  arc4random_uniform(13) + 1)