swift 闭包的比较写法

let names = ["Chris", "Alex", "Ewa", "Barry", "Daniella"]

func backwards(s1:String, s2:String) -> Bool {
    return s1 > s2;
}

var reversed = names.sort(backwards)

reversed = names.sort({(s1:String, s2:String) -> Bool in
    return s1 > s2;
})

reversed = names.sort({s1, s2 in return s1 > s2})

reversed = names.sort({$0 > $1})

reversed = names.sort(>)