Guard关键字

没有guard

let money = true
let idcard  = true
func online2(age : Int,money:Bool,idcard:Bool){
    if age >= 18 {
        if money {
            if idcard {
                print("一起来开黑吖")
            }else{
                print("回去带身份证吧")
            }
        }else{
             print("回去拿钱")
        }
    }else {
        print("还未成年呢")
    }
}
//调用
online2(age: age, money: money, idcard: idcard)

有guard

func online1(age : Int){
    //判断年龄
    guard age >= 18 else {
        print("还未成年呢")
        return
    }
    //判断是否有钱
    guard money else {
        print("回去拿钱")
        return
    }
    //判断是否带了身份证
    guard idcard else {
         print("回去带身份证吧")
        return
    }
    print("一起来开黑吖")
}