Swift 控制流 Control Flow

• while

var startIndex = 0
var finalValue = 10
while startIndex < finalValue {
    startIndex += 1
}
print("Game Over")

• repeat while

repeat {
    startIndex += 1
    print(startIndex)
} while startIndex < finalValue

• switch

let someCharacter:Character = "z"
switch someCharacter {
case "a":
    print("a")
case "z":
    print("z")
default:
    print("没找到")
}

• where

let point = (1,-1)
switch point {
case let(x,y) where x == y:
    print("x == y")
default:
    print("x != y")
}