swift 开篇

苹果的WWDC ，除了公布了os x 10.10 和IOS8 外，还推出了Swift。具体点击这里

代码整体风格有点像Java，也有点像javascript。

以下给出一些代码段（来自苹果官方手冊）：

println("Hello, world")

“var myVariable = 42
myVariable = 50
let myConstant = 42”

摘录来自: Apple Inc. “The Swift Programming Language”。 iBooks. https://itun.es/cn/jEUH0.l

“var shoppingList = ["catfish", "water", "tulips", "blue paint"]
shoppingList[1] = "bottle of water"

var occupations = [
    "Malcolm": "Captain",
    "Kaylee": "Mechanic",
]
occupations["Jayne"] = "Public Relations”

摘录来自: Apple Inc. “The Swift Programming Language”。 iBooks. https://itun.es/cn/jEUH0.l

“let vegetable = "red pepper"
switch vegetable {
case "celery":
    let vegetableComment = "Add some raisins and make ants on a log."
case "cucumber", "watercress":
    let vegetableComment = "That would make a good tea sandwich."
case let x where x.hasSuffix("pepper"):
    let vegetableComment = "Is it a spicy \(x)?"
default:
    let vegetableComment = "Everything tastes good in soup."
}
”

摘录来自: Apple Inc. “The Swift Programming Language”。 iBooks. https://itun.es/cn/jEUH0.l

“class NamedShape {
    var numberOfSides: Int = 0
    var name: String

    init(name: String) {
        self.name = name
    }

    func simpleDescription() -> String {
        return "A shape with \(numberOfSides) sides."
    }
}”

摘录来自: Apple Inc. “The Swift Programming Language”。 iBooks. https://itun.es/cn/jEUH0.l

“class Square: NamedShape {
    var sideLength: Double

    init(sideLength: Double, name: String) {
        self.sideLength = sideLength
        super.init(name: name)
        numberOfSides = 4
    }

    func area() ->  Double {
        return sideLength * sideLength
    }

    override func simpleDescription() -> String {
        return "A square with sides of length \(sideLength)."
    }
}
let test = Square(sideLength: 5.2, name: "my test square")
test.area()
test.simpleDescription()”

摘录来自: Apple Inc. “The Swift Programming Language”。 iBooks. https://itun.es/cn/jEUH0.l