How to roll a dice using GameplayKit and GKRandomDistribution

Swift version: 5.1

Paul Hudson    @twostraws    May 28th 2019

GameplayKit's random number generator includes help constructors that produces numbers in a specific range, simulating a six-sided die and a 20-sided die. To get started you should import the GameplayKit framework like this:

import GameplayKit

You can then create a virtual six-sided die and "roll" it like this:

let d6 = GKRandomDistribution.d6()
d6.nextInt()

For a 20-sided die, do this:

let d20 = GKRandomDistribution.d20()
d20.nextInt()

If you want to set your own range for the virtual die, there's a special constructor just for you:

let massiveDie = GKRandomDistribution(lowestValue: 1, highestValue: 556)
massiveDie.nextInt()

Available from iOS 9.0 – see Hacking with Swift tutorial 35

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