2016. 11. 19. 12:33ㆍSwift
// Enumerations
// Enumeration Syntax
// enum SomeEnumeration {
// // enumeration definition goes here
// }
enum CompassPoint {
case north
case south
case east
case west
}
enum Planet {
case mercury, venus, earth, mars,
jupiter, saturn, uranus, neptune
}
var directionToHead = CompassPoint.west
directionToHead = .east
directionToHead = .south
switch directionToHead {
case .north:
print("Lots of planets have a north")
case .south:
print("Watch out for penguins")
case .east:
print("Where the sun rise")
case .west:
print("Where the skies are blue")
}
let somePlanet = Planet.earth
switch somePlanet {
case .earth:
print("Mostly harmless")
default:
print("Not a safe place for humans")
}
// Associated Values
enum Barcode {
case upc(Int, Int, Int, Int)
case qrCode(String)
}
var productBarcode = Barcode.upc(8, 85909, 51226, 3)
productBarcode = .qrCode("ABCDEFGHIJKLMNOP")
switch productBarcode {
case .upc(let numberSystem, let manufacturer, let product, let check):
print("UPC: \(numberSystem), \(manufacturer), \(product), \(check).")
case .qrCode(let productCode):
print("QR code: \(productCode)")
}
// 데이터형을 앞으로 빼서 간결하게 만들 수 있다.
switch productBarcode {
case let .upc(numberSystem, manufacturer, product, check):
print("UPC: \(numberSystem), \(manufacturer), \(product), \(check).")
case let .qrCode(productCode):
print("QR code: \(productCode)")
}
//Raw Values
enum ASCIIControlCharacter: Character {
case tab = "\t"
case lineFeed = "\n"
case carriageReturn = "\r"
}
enum Planet1: Int {
case mercury = 1, venus, earth, mars, jupiter, saturn, uranus, neptune
}
enum CompassPoint1: String {
case north, south, east, west
}
let earthsOrder = Planet1.earth.rawValue
let sunsetDirection = CompassPoint1.west.rawValue
let sunsetDirection_hash = CompassPoint1.west.hashValue
let possiblePlanet = Planet1(rawValue: 7)
let positionToFind = 3
if var somePlanet = Planet1(rawValue: positionToFind) {
switch somePlanet {
case .earth:
print("Mostly harmless")
default:
print("Not a safe place for humans")
}
} else {
print("There isn't a planet at Position \(positionToFind)")
}
// Recursive Enumerations
enum ArithmeticExpression {
case number(Int)
indirect case addition(ArithmeticExpression, ArithmeticExpression)
indirect case multiplication(ArithmeticExpression, ArithmeticExpression)
}
indirect enum ArithmeticExpression1 {
case number(Int)
case addition(ArithmeticExpression, ArithmeticExpression)
case multiplication(ArithmeticExpression, ArithmeticExpression)
}
let five = ArithmeticExpression.number(5)
let four = ArithmeticExpression.number(4)
let sum = ArithmeticExpression.addition(five, four)
let product = ArithmeticExpression.multiplication(sum, ArithmeticExpression.number(2))
func evaluate(_ expression: ArithmeticExpression) -> Int {
switch expression {
case let .number(value):
return value
case let .addition(left, right):
return evaluate(left) + evaluate(right)
case let .multiplication(left, right):
return evaluate(left) * evaluate(right)
}
}
print(evaluate(sum))
print(evaluate(product))
출처 : The Swift Programming Language(iBook)