閉包與陣列的Map方法

範例：

var numberArray = [1,3,5,2,4,6]

let newNumber = numberArray.map ({
    (number:Int) in
    print(number)

})
//印出：1,3,5,2,4,6

若不是要「印出來每次的結果」，而是要「回傳的範例」：

var numberArray = [1,3,5,2,4,6]

let newNumber = numberArray.map ({
    (number:Int)->Int in
    return number

})
//印出：1,3,5,2,4,6

轉成省略簡寫的Closure：

var numberArray = [1,3,5,2,4,6]

let newNumber = numberArray.map {in $0}
print(newNumber)
//印出：1,3,5,2,4,6

練習：請將下列Closure簡寫化

var numberArray = [1,3,5,2,4,6]

let newNumber = numberArray.map({
    (a:Int) -> String in
    return "This is number \(a)"
})
print(newNumber)
//印出：This is number 1, This is number 2....

解答：

var numberArray = [1,3,5,2,4,6]

let newNumber = numberArray.map{"This is number \($0)"}

print(newNumber)
//印出：This is number 1, This is number 2....