目錄
- 代碼執行個體
- 答案揭曉
代碼執行個體
沒有怎麼接觸過Swift,直接上手看的代碼,遇到
_
符号,特此記錄。
let _ = 100
var _ = 200
for _ in 0...3 {
print("do something...")
}
func fun1( _ x: Int, _ y: Int){
print("do something...")
}
func add(x:Int,y:Int) -> Int{
return x+y
}
_ = add(x: 1, y: 2)
答案揭曉
Swift裡的
_
(下劃線)是省略符号,代表省略的意思,詳細作用可看下方注釋:
let _ = 100 //無實際含義
var _ = 200 //無實際含義
//循環三次,省略計數器
for _ in 0...3 {
print("do something...")
}
//去掉參數标簽
func fun1( _ x: Int, _ y: Int){
print("do something...")
}
fun1(10,20)
//省略傳回值
func add(x:Int,y:Int) -> Int{
return x+y
}
_ = add(x: 1, y: 2)