Swift Lang tuples another way

score2

// might like this as better use of Tuple. Not sure. Return Tuple, use its named elements
// code is asking for a frame object, i think, but wanted to try Tuples

    func frameScore(index:Int) -> (score: Int, step: Int) {
        if isStrike(index) {
            return (rolls[index] + twoRolls(index+1), 1)
        } else if isSpare(index) {
            return (twoRolls(index) + rolls[index+2], 2)
        } else {
            return (twoRolls(index), 2)
        }
    }

    func score() -> Int {
        var sum = 0
        var index = 0
        for frame in 1...10 {
            let frameInfo = frameScore(index)
            sum += frameInfo.score
            index += frameInfo.step
        }
        return sum
    }

Use the tuples in score, why not?