New in Swift 4.2

CaseIterable

The CaseIterable protocol provides an allCases method that turns all of your cases into an array.

enum Pasta: String, CaseIterable {
    case canneloni = "Cannelloni pasta"
    case fusilli = "Fusilli pasta"
    case linguini = "Linguini pasta"
    case taliatelle = "Taliatelle pasta"
}

Pasta.allCases.forEach{ pastaType in
    print("\(pastaType.rawValue)")
}

Random number generator

Random number generator for range. Cleaner syntax than arc4random_uniform()

let randomNumber = Int.random(in: 1...1000)

allSatisfy

.allSatisfy returns a Bool for conditions specified on an array

let scores = [85, 84, 95, 92]
let passed = scores.allSatisfy{ $0 >= 85 } // returns Bool

removeAll

.removeAll now allows you to specify a filter to remove items from an array

var theBigLebowski = ["The Dude", "Angry Walter", "Maude Lebowski", "Donny Kerabatsos", "The Big Lebowski", "Little Larry Sellers"]
theBigLebowski.removeAll{ $0.contains("Lebowski")}

toggle()

.toggle() allows you to toggle a boolean without having to assign it

var myBool = true
myBool.toggle() // flips to false