haranicle

//  エラーハンドリング専用構文

do {
	// エラーが発生する可能性があるコード
} catch {
	// エラー発生時の処理
}

// 例
do {

haranicle

if case let .OSX(version) = platform {
	print(version)
}

if case let value? = optionalValue {
}

if case let (a?, b?, c?) = (optionalA, optionalB, optionalC) {
	// optionalA,B,Cすべてがoptionalじゃないときだけ実行される
	print(\(a)\(b)\(c))

haranicle

Realm().write {
    Realm().deleteAll()
}

let turtle = Animal()
turtle.name = "Turtle"
turtle.legCount = 4

Realm().write {
    Realm().add(turtle)

haranicle

alias imgdiff='composite -compose difference'

haranicle

class HTMLElement {
    
    let name: String
    let text: String?
    
    // プロパティでasHTMLへのstrong参照を持っている
    lazy var asHTML: Void -> String = { // nameとtextを使いたいからlazy
        // Closure内でselfのプロパティをキャプチャしている
        if let text = self.text {
            return "<\(self.name)>\(text)</\(self.name)>"

haranicle

let sum: ([Int]) -> Int
sum = { values in
    if values.isEmpty {
        return 0
    }
    else {
        return values.first! + sum(Array(values.dropFirst()))
    }
}

haranicle

struct Location {
    var x:Int
    var y:Int
}

var l1 = Location(x: 10, y: 20)
l1.x = 30

let l2 = Location(x: 10, y: 20)
l2.x = 30 // Cannot assign to property

haranicle

public override static func initialize() {
    struct Static {
        static var token: dispatch_once_t = 0
    }
    
    struct SwizzlingSelector {
        let original:Selector
        let swizzled:Selector
    }
    

haranicle

protocol P: Hashable {}

func ==(lhs: S, rhs: S) -> Bool { return lhs.name == rhs.name }
struct S: P {
    var name = "struct"
    var hashValue: Int { get{ return name.hash } }
}

let setS: Set<S> = [S()]
let setP: Set<P> = [S()] // Protocol 'P' can only be used as a generic constraint because it has Self or assosiated type requirements

haranicle

protocol P1 {
}
protocol P2 {
    typealias A = Self
}

let arr1: Array<P1> = []
let arr2: Array<P2> = [] // Protocol 'P2' can only be used as a generic constraint because it has Self or associated type requirements