[swift] How does one generate a random number in Apple's Swift language?

Swift 4.2

Bye bye to import Foundation C lib arc4random_uniform()

// 1  
let digit = Int.random(in: 0..<10)

// 2
if let anotherDigit = (0..<10).randomElement() {
  print(anotherDigit)
} else {
  print("Empty range.")
}

// 3
let double = Double.random(in: 0..<1)
let float = Float.random(in: 0..<1)
let cgFloat = CGFloat.random(in: 0..<1)
let bool = Bool.random()
  1. You use random(in:) to generate random digits from ranges.
  2. randomElement() returns nil if the range is empty, so you unwrap the returned Int? with if let.
  3. You use random(in:) to generate a random Double, Float or CGFloat and random() to return a random Bool.

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