Swift 101 - nil

The supplementary Swift Playground to Swift 101 - nil.

Playground source

/*:
 # Swift 101 - nil
 https://medium.com/pretty-swifty/swift-101-nil-423813b56dfb
 A super quick blog to go over a key keyword in Swift - `nil`.
 */
import UIKit
var notNillableInt: Int = 1 // The key bit here is `: Int`, note that there is no `?`.
//Uncomment the line below to see the compiler complain about assigning notNillableInt to nil.
//notNillableInt = nil
var nillableInt: Int? //This variabled can be assigned nil, here or in the future.
nillableInt = 1
nillableInt = nil