编辑代码

function Max(){
     let num=5
     return function(){
          return num++
     }
}
const {log} = console
log(Max()())
let sum = Max()
log(sum())
log(sum())
log(sum())
//自执行函数！
let ss = function sum(s=4){
    log(++s) 
}();
(function(){
    log("123")
}())
function fnc(){
    var arr=[]
    for(var i=0;i<1230;i++){
        (function(n){
            arr[i]=function(){
                return n
            }
        })(i)
    }
    return arr
}
var btn = fnc()
log(btn[0]())
log(btn[3]())
log(btn[223]())