To swiftly go where no OS has gone before

Swift & iOS
Paul Ardeleanu
pa@h24.io
@pardel
Copyleft 2014 me

CuriosMinds, Brasov, Sept 18th 2014 Slide 2

An Android, an iOS, a Blackberry and a
Windows Mobile developer walk into a bar…

The barman looks at them & says…

The barman looks at them & says…
Gee, it must be in town

To swiftly go where no
other language has
gone before

Good artists copy,
Real artists steal

Everything is a remix
https://www.flickr.com/photos/mugley/800999028/

The talk about that new
programming language
everyone talks about
but nobody really uses…

CuriosMinds, Brasov, Sept 18th 2014 Slide 1 2

#freeJonyIve

It’s all about the users
https://www.flickr.com/photos/wyogirl13/6455191187

It’s all about the users.
https://www.flickr.com/photos/wyogirl13/6455191187

AAPL

Products

Software

App Stores

‣ maximise the number of developers
CuriosMinds, Brasov, Sept 18th 2014 Slide
‣ keeping existing developers happy
31
2 more things…

‣ 30 year old language
‣ drastically different from other languages
‣ not entirely future-proof
32
Objective-C

LLVM & Clang
Apps For Good, London, June 29th 2012 Slide 3 4 Hello24 Ltd. (c) 2012

LLVM & Clang
gcc => llvm-gcc => llvm
Apps For Good, London, June 29th 2012 Slide 3 4 Hello24 Ltd. (c) 2012

Objective-C without the C
36
Swift

Objective-C without the C
36
Swift
Objective-C is to Swift <=> cat is to cattle

Safety - constants vs variables

let theAnswer = 42

let theAnswer = 42
var numberBooks = 1

let theAnswer = 42
var numberBooks = 1
var numberBooks: Int = 1

Safety - no implicit conversion

var numberBooks = 1

var numberBooks = 1
numberBooks = 2.5

var numberBooks = 1
numberBooks = 2.5 ❗️

var numberBooks = 1
numberBooks = Int(2.5)

var numberBooks = 1
numberBooks = Int(2.5) ✔

Safety - switch
switch index {
case 1:
println("first")
case 2, 3:
println("second or third")
case 4...10:
println("top 10")
default:
println("others...")
}

Tuples

Tuples
let http404Error = (404, "Not Found")

Tuples
let x = 1
let y = 2
let point = (x, y)

Tuples
let x = 1
let y = 2
let point = (x, y)
point.0

Tuples
let x = 1
let y = 2
let point = (x, y)
point.0
let origin = (x: 200, y: 100)
origin.y

Tuples

Tuples
// Original
var fibonacci = 1
var prev = 0
while fibonacci < 100 {
var prev_tmp = fibonacci
fibonacci += prev
prev = prev_tmp
println(fibonacci)
}

Tuples
// Original
var fibonacci = 1
var prev = 0
while fibonacci < 100 {
var prev_tmp = fibonacci
fibonacci += prev
prev = prev_tmp
println(fibonacci)
}
// tuples
var fibonacci_t = 1
var prev_t = 0
while fibonacci_t < 100 {
(prev_t, fibonacci_t) = (fibonacci_t, fibonacci_t + prev_t)
println(fibonacci_t)
}

Functions as
1st class citizens

Functions
func greetingAt(hour: Int) -> (String) -> String {
}
func morningGreeting(name: String) -> String {
return "Good morning (name)"
}
func afternoonGreeting(name: String) -> String {
return "Good afternoon (name)"
}
return hour < 12 ? morningGreeting : afternoonGreeting

Functions
}
}
}
greetingAt(11)("Paul")

Functions
}
}
}
"Good morning Paul”
"Good afternoon Paul"

Closures

Closures
func greetWithMessage(name: String, message: (String) -> String) -> String
{
return message(name);
}

Closures
{
}
greetWithMessage("Paul",
{ (name: String) -> String in
}
)

Closures
{
}
}
)
greetWithMessage("Paul", { name in
})

Closures
{
}
}
)
})
greetWithMessage("Paul") { name in
}

Closures
{
}
}
)
})
greetWithMessage("Paul") { name in
}
greetWithMessage("Paul") { return "Good morning ($0)" }

Module 01 Slide 5 2 Hello24 Ltd. (c) 2014
New Playground

Empty Playground

Playground

Fibonacci

Playground - Timeline

Playgrounds

Module 01 Slide Hello24 Ltd. (c) 2014
‣ Interactive experience
‣ Immediate feedback
‣ Watch code progression through loops
60
Playgrounds

‣ Easy way to
‣ prototype
‣ test snippets of code
60
Playgrounds

‣ Easy way to
‣ prototype
‣ test snippets of code
‣ CAREFUL! Executed automatically.
60
Playgrounds

REPL
Read–eval–print loop

REPL
$ which swift
/usr/bin/swift

REPL
$ which swift
/usr/bin/swift
$ swift -v
Swift version 1.0 (swift-600.0.51.3)
Target: x86_64-apple-darwin14.0.0
<unknown>:0: error: the SDK 'MacOSX10.9.sdk' does not
support Swift

man swift

REPL

REPL
$ swift -v
…
<unknown>:0: error: the SDK 'MacOSX10.9.sdk' does not support Swift

REPL

REPL
$ swift -v

REPL
$ swift -v
/Applications/Xcode-Beta.app/Contents/Developer/usr/bin/lldb "--repl=-target
x86_64-apple-darwin14.0.0 -target-cpu core2 -sdk /Applications/Xcode-
Beta.app/Contents/Developer/Platforms/MacOSX.platform/Developer/SDKs/
MacOSX10.10.sdk -color-diagnostics"

REPL
$ swift -v
/Applications/Xcode-Beta.app/Contents/Developer/usr/bin/lldb "--repl=-target
x86_64-apple-darwin14.0.0 -target-cpu core2 -sdk /Applications/Xcode-
Beta.app/Contents/Developer/Platforms/MacOSX.platform/Developer/SDKs/
MacOSX10.10.sdk -color-diagnostics"
$ swift
Welcome to Swift! Type :help for assistance.

REPL
$ swift
Welcome to Swift! Type :help for assistance.
1> 1 + 2
$R0: Int = 3
2> "once upon a time"
$R1: String = "once upon a time"
3> $R1 + " there were ($R0) bears"
$R2: String = "once upon a time there were 3 bears"
4> println($R2)
once upon a time there were 3 bears

‣ iOS 8 released yesterday
‣ Swift is v.1.0 as of Sept 9th
‣ Xcode 6.0.1 released yesterday
‣ Apps written in Swift started being accepted on Sept 9th
68
Now!

Resources

My Book
pa@h24.io

Swift project

Bridging

//
// STDataObject.swift
//
import Foundation
import CoreData
class STDataObject: NSManagedObject {
@NSManaged var uuid: String?
@NSManaged var sync_uuid: String?
@NSManaged var is_active: NSNumber
class func managedObjectContext() -> NSManagedObjectContext? {
var appDelegate = UIApplication.sharedApplication().delegate
as AppDelegate
return appDelegate.managedObjectContext
}
…
}

Fizz Buzz classic

Fizz Buzz classic
let fizzBuzz = ({ (n: Int) -> String in
if( 0 == (n % 3 + n % 5)) { return "FizzBuzz" }
if( 0 == n % 3) { return "Fizz" }
if( 0 == n % 5) { return "Buzz" } else { return "(n)" }
})
fizzBuzz(1)
fizzBuzz(2)
fizzBuzz(3)
fizzBuzz(5)
fizzBuzz(9)
fizzBuzz(10)
fizzBuzz(15)

Fizz Buzz classic
if( 0 == n % 3) { return "Fizz" }
})
fizzBuzz(1)
fizzBuzz(2)
fizzBuzz(3)
fizzBuzz(5)
fizzBuzz(9)
fizzBuzz(10)
fizzBuzz(15)
“1”
“2”
“fizz”
“buzz”
“fizz”
“buzz”
“fizzbuzz”

Swift Fizz Buzz

Swift Fizz Buzz
let swiftFizzBuzz = ({ (aNumber: Int) -> String in
switch (aNumber % 3, aNumber % 5 ) {
case (0, 0):
return "FizzBuzz"
case (0, _):
return "Fizz"
case (_, 0):
return "Buzz"
default:
return "(aNumber)"
}
})
swiftFizzBuzz(1)
swiftFizzBuzz(2)
swiftFizzBuzz(3)
swiftFizzBuzz(5)
swiftFizzBuzz(9)
swiftFizzBuzz(10)
swiftFizzBuzz(15)

Swift Fizz Buzz
case (0, 0):
return "FizzBuzz"
case (0, _):
return "Fizz"
case (_, 0):
return "Buzz"
default:
return "(aNumber)"
}
})
swiftFizzBuzz(1)
swiftFizzBuzz(2)
swiftFizzBuzz(3)
swiftFizzBuzz(5)
swiftFizzBuzz(9)
swiftFizzBuzz(10)
swiftFizzBuzz(15)
“1”
“2”
“fizz”
“buzz”
“fizz”
“buzz”
“fizzbuzz”

Fizz Buzz - side by side
if( 0 == n % 3) { return "Fizz" }
})
case (0, 0):
return "FizzBuzz"
case (0, _):
return "Fizz"
case (_, 0):
return "Buzz"
default:
return "(aNumber)"
}
})

Thank you!
Paul Ardeleanu
pa@h24.io
@pardel
Copyleft 2014 me

To swiftly go where no OS has gone before

Recommended

Recommended

More Related Content

Viewers also liked

Viewers also liked (20)

Similar to To swiftly go where no OS has gone before

Similar to To swiftly go where no OS has gone before (8)

More from Paul Ardeleanu

More from Paul Ardeleanu (20)

Recently uploaded

Recently uploaded (20)

To swiftly go where no OS has gone before