#optionals

[farwiayas3-blog]

Optionals: NPEs and Design Practices - https://goo.gl/C7ESM5 - #Auto_Insurance, #Design, #NPEs, #Optionals, #Practices

[script-ease]

swift-evolution/0054-abolish-iuo.md at master · apple/swift-evolution · GitHub

[script-ease]

[script-ease]

Fortunately you can do that in Swift 2 with an if case: if case .Adress(let addressString) = addess { // do something with addressString }

[cat-notes-blog]

Swift Optionals

Optionals are enums. With case None, and case Some(T). <T> is just a generic. 

let x: String? = nil

is the same as 

let x = Optional<String>.None

let x: String? = “hello”

is the same as

let x = Optional<String>.Some(”hello”)

exclamation mark and question marks are syntactic sugar. 

Optionals can be “Chained”: 

if let x = display?.text?.hashValue {...}

chain the optionals. So if any of these are uninitialized, then the whole thing is just nil. 

There is also a default operator for optionals. 

display.text = s ?? “ ”

[konradowyitblog-blog]

Since the advent of Swift, optionals were hard to grasp and understand. This blog will explain what an implicitly unwrapped optional is and when to use it.

[punkfolio]

I occasionally make sculptures I place in the urban landscape