init使用，函數(shù)調(diào)用

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

        init(name: String) {
            self.name = name
            print(self.name)
        }
        
        func simpleDescription() -> String {
            return "A shape with \(numberOfSides) sides."
        }
        
    }
    NamedShape(name:"liu")
    var narr = NamedShape(name:"liu").simpleDescription()
    print(narr)

try?

另一種處理錯誤的方式使用try?將結(jié)果轉(zhuǎn)換為可選的。如果函數(shù)拋出錯誤，該錯誤會被拋棄并且結(jié)果為nil。否則的話，結(jié)果會是一個包含函數(shù)返回值的可選值。
let printerSuccess = try? send(job: 1884, toPrinter: "Mergenthaler")
let printerFailure = try? send(job: 1885, toPrinter: "Never Has Toner")