How to shuffle an array using arc4random_uniform()
Swift version: 5.6
Modern Swift code will use Swift’s own shuffle() and shuffled() methods, but sometimes you might find code that does it by hand using arc4random_uniform() or similar.
Nate Cook wrote a simple shuffle() extension to arrays that implements the Fisher-Yates shuffle algorithm in Swift. Here's the code:
extension Array {
mutating func customShuffle() {
for i in 0 ..< (count - 1) {
let j = Int(arc4random_uniform(UInt32(count - i))) + i
swapAt(i, j)
}
}
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