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Note about Swift Book

👍 感謝學員免費獲得的電子書：彼得潘的 Swift 程式設計入門

Ch2. Playground

• Swift strings use double quotes instead of single quote!

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var name = "Jamie"
var intro = "my name is \(name). hello world"

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var age: Int = 18
var age = 18 // type inference
var age // <-- error! neither type declaration nor initialized value.

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var number2 = 15
var number3 : Int
number2 = number3 // <-- error! wihtout value

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for i in 1..10 {
	print("hello \(i)")
}

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while num < 10 {
	num = number +1
}

repeat {
	number = number +1
} while number < 10

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if age < 20 {
	print("hello world")
}

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Notes about Swift Book

Ch2. Playground

• Swift strings use double quotes instead of single quote!
• Reference: How to print double quotes inside “”?
  1. use backslash to escape
  2. use """ delimiter
  3. enhanced delimiters (swift 5)

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import AVFoundation
import AVKit
import UIKit

class ViewController: UIViewController {
  @IBOutlet weak var lyricsLabel: UILabel!
  @IBOutlet weak var videoView: UIView!
  
  var player: AVPlayer?
  var timer: Timer?

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import UIKit

// Point definition for json object
class Point: Decodable {
  let x, y: Int
  let color: String
  
  // load all points from json file.
  //
  // ref: https://stackoverflow.com/a/50042872