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Tuple shuffle exists in Swift.

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var a = "one", b = "two"
(a, b) = (b, a)
print(a) // "two"
print(b) // "one"
 
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var items = ["one", "two", "three"]
(items[0], items[2]) = (items[2], items[0])
print(items) // "["three", "two", "one"]"

With an example of array shuffle using Fisher-Yates, let’s leverage tuple shuffle instead of swap

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extension CollectionType {
    /// Return a copy of `self` with its elements shuffled
    func shuffle() -> [Generator.Element] {
        var list = Array(self)
        list.shuffleInPlace()
        return list
    }
}

extension MutableCollectionType where Index == Int {
    /// Shuffle the elements of `self` in-place.
    mutating func shuffleInPlace() {
        // empty and single-element collections don't shuffle
        if count < 2 { return }

        for i in 0..<count - 1 {
            let j = Int(arc4random_uniform(UInt32(count - i))) + i
            guard i != j else { continue }
            (self[i], self[j]) = (self[j], self[i])
            // instead of swap(&self[i], &self[j])
        }
    }
}

[1, 2, 3, 4, 5, 6, 7, 8, 9, 10].shuffle()

Reference

Contents
  1. 1. Reference