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iOS Build a Simple iPhone App with Swift Creating a Data Model Finishing Up Our Model

Posted by Aaron Williamson
Aaron Williamson
10,421 Points

How does Pasan know to cast the arc4random_uniform as an Int?

It already looks like an Int before he casts it so how do you know to cast as an Int before proceeding?

Thomas Lahoud
Thomas Lahoud
6,092 Points
Thomas Lahoud
Thomas Lahoud
6,092 Points

I was also wondering this. I think it has something to do with "typecasting" through a function/method rather than putting (Int) at the start of the line?

Drew Carver
Drew Carver
5,189 Points
Drew Carver
Drew Carver
5,189 Points

Was wondering the same..

1 Answer

Michael Liendo
Michael Liendo
15,326 Points
Michael Liendo
Michael Liendo
15,326 Points

here is my commented code, hope this helps :)

func randomFact() -> String {

        //the count property returns an Int so first we cast it to an uInt32
        var unsignedArrayCount = UInt32(factsArray.count)

        //arc4random_uniform takes in the Uint32 and returns a random number
        var unsignedRandomNumber = arc4random_uniform(unsignedArrayCount)

        //we then take the random number and convert it back to an int so we can use it as a subscript in our array.
        var randomNumber = Int(unsignedRandomNumber)

        return factsArray[randomNumber]
    }
Aaron Williamson
Aaron Williamson
10,421 Points

Thanks Michael, after taking a break for a few hours and coming back it makes sense what he's doing.