[swift] code log, day 5

iBooks 의 SWIFT 4 를 통해 언어 공부 중입니다. 이때 사용된 책 속의 코드 및 연습문제 등의 코드 로그입니다.

아래 코드들은 Github 에서도 다운받을 수 있습니다.

SWIFT_Playground_Excersice: https://github.com/youp-han/SWIFT_Playground_Excersice

//------------------------------------------------------------

// 코드 로그 입니다.

// Day 5

do {

    let printerResponse = try send(job: 1440, toPrinter: "Gutenberg")

    print(printerResponse)

} catch PrinterError.onFire{

    print("I'll just put this over here, with the rest of the fire.")

} catch let printerError as PrinterError{

    print("Printer error: \(printerError).")

} catch {

    print(error)

}

//optional try (try?) will convert result to an optional.

//so if the function throws an error, the error is discarded and

// result is nil

let printerSuccess = try? send(job: 1884, toPrinter: "Mergenthaler")

let printerFailure = try? send(job: 1884, toPrinter: "Never Has Toner")

//defer

var fridgeIsOpen = false

let fridgeContent = ["milk", "eggs", "leftovers"]

func fridgeContains(_ food: String) -> Bool {

    fridgeIsOpen = true

    defer{

        fridgeIsOpen = false

    }

    

    let result = fridgeContent.contains(food)

    return result

}

fridgeContains("banana")

print(fridgeIsOpen)

//Generics

func makeArray<Item>(repeating item: Item, numberOfTimes: Int) -> [Item]{

    var result = [Item]()

    for _ in 0..<numberOfTimes {

        result.append(item)

    }

    return result

}

makeArray(repeating: "knock", numberOfTimes: 4)

enum OptionalValue<Wrapped>{

    case none

    case some(Wrapped)

}

var possibleInteger: OptionalValue<Int> = .none

print("possibleinteger = \(possibleInteger)")

possibleInteger = .some(100)

print("possibleinteger (100) = \(possibleInteger)")

func anyCommonElements<T: Sequence, U: Sequence> (_ lhs: T, _ rhs: U) -> Bool where T.Iterator.Element: Equatable, T.Itertor.Element == U.Iterator.Element{

    for lhsItem in lhs{

        for rhsItem in rhs{

            if lhsItem == rhsItem {

                return true

            }

        }

    }

    

    return false

}

anyCommonElements([1,2,3], [3])