Developing Swift - Moving towards the future

Developing SwiftMoving towards the future

About Inaka• Started in 2010.

• Acquired by Erlang Solutions in 2014.

• We build end-to-end applications with Erlang, Ruby, Web, iOS and Android components.

• We develop highly concurrent application servers such as Whisper and TigerText.

• We're active contributors to the open-source community.

About Me• Pablo Villar.

• iOS Developer.

• Have been working at Inaka for last 2 years.

• Have been working as iOS dev for last 4 years.

• Clean code lover!

What’s Swift?

Why Swift?

How to Swift?

What’s behind Swift?

What’s Swift for?

A little bit of history…

Early 1980's Objective-C

2007 iPhone is born

Late 1980's NeXT license AppKit, FoundationKit

1997 Apple purchases NeXT

2010 iPad is born2015 Watch is born

A little bit of history…

Early 1980's Objective-C

2007 iPhone is born

Late 1980's NeXT license AppKit, FoundationKit

1997 Apple purchases NeXT

2010 iPad is born2015 Watch is born

2014

Swift

2007~2015 (last 8 years)

… ?

IPHONE

IPAD

WATCH

IPOD TOUCH

OBJ-C SWIFT

1980 - Nowadays 2014 - Nowadaysto be deprecated… (?) to keep growing…

A very little bit of history of Swift…

June 2014 Swift 1.0

April 2015 Swift 1.2

October 2015 Swift 2.0

Today

No backwards compatibility

OPEN SOURCE!

BE ADAPTATIVE!

BE PATIENT!

Y U NO WORK?!?!?!

BE TOLERANT!

Y U NO CLEAR?!?!?!

BE ENTHUSIASTIC!

BE CHALLENGED!

Last… Not least.

Now… What you’ve been waiting for…


code!


code!

wasn’t it…?


code!

SAFETY

Optionals

wasn’t it…?


code!

SAFETY

Optionals

String?

Stringnil

wasn’t it…?

Why Optionals?

Things can be nullable

You need a mechanism to properly deal with that

Swift is statically typed

+

Why Optionals?




+

String “A regular String, it can’t be nil”

Why Optionals?




+

String “A regular String, it can’t be nil”

String? “A String that can be nil”

Optional Type

String? “A String that can be nil”

String? “A

An Optional that can be a String

…or can eventually be nil

String?

Stringnil

String? “A



String?

Stringnil Behind the scenes…

enum Optional<T> { case None // nil case Some(T) // a T }

String? “A



String?

Stringnil Behind the scenes…

enum Optional<T> { case None // nil case Some(T) // a T }

Optional<String>

Int?

Intnil

A little, yet valuable example…

Int?

Intnil


var age: Int?

Int?

Intnil


// We prompt the user to enter his/her age.

var age: Int?

Int?

Intnil


func greetingForPersonWithAge(age: Int) -> String {


var age: Int?

switch age { case 0...2: return "Hello baby!" case 3...5: return "How are you doing, toddler?” case 6...12: return "What's up, kid?" case 13...18: return "Yo, what's up?" default: return "Hello, mister!" } }

Int?

Intnil




var age: Int?

let greeting = greetingForPersonWithAge(age)

println(greeting)


Int?

Intnil


func


var


println(

} }

Int?

Intnil




var age: Int?

// Int? and Int are not compatible, // You have to deal with it


println(greeting)

} }

But, how to…

?

But, how to…

?

var age: Int? = nil


if let knownAge = age { let greeting = greetingForPersonWithAge(knownAge) println(greeting) } else { println("Hello") // No age. }

But, how to…

?

var age: Int? = nil



Init to nil by default

But, how to…

?

var age: Int? = nil




"Unwrap" the optional

But, how to…

?

var age: Int? = nil





Use the unwrapped one, which is NOT an optional

but an Int

But, how to…

?

var age: Int? = nil






but an Int

Define a separated behavior to deal with nil values

But, how to…

?

var age: Int? = nil






but an Int

Define a separated behavior to deal with nil values

SAFETY




var age: Int?

if let knownAge = age {

let greeting = greetingForPersonWithAge(knownAge) println(greeting) } else {

println("Hello") // Or show alert. Or whatever.

}


(Let’s get ALL the juice from it!)




var age: Int?

if let knownAge = age {

let greeting = greetingForPersonWithAge(knownAge) println(greeting) } else {

println("Hello") // Or show alert. Or whatever.

}

} }

(Let’s get ALL the juice from it!)

From this point on, we don’t have to worry about nullability ever again!

In conclusion…

In conclusion…

• Swift changes the way we use to think when it comes to develop mobile apps.

In conclusion…


• The language has just been born and it’s growing really fast.

In conclusion…


• We’re still in a phase in which there are many bugs and downsides.


In conclusion…


• We’re still in a phase in which there are many bugs and downsides.


• But still, promises are big! Swift is the future.

For more info… Check these out!

https://developer.apple.com/videos/wwdc/2014/


https://developer.apple.com/swift/resources/

http://www.objc.io/

Cool blogs to learn from…

http://nshipster.com/

Inaka’s webpage:http://inaka.net/

http://inaka.net/blog



https://developer.apple.com/swift/resources/

http://www.objc.io/

http://nshipster.com/

http://inaka.net/

http://inaka.net/blog

Developing Swift - Moving towards the future

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