SOURCE

var list = [8,7,6,5,4]
list.map((i,index,arr)=>{arr[index] = 8;console.log(i,index,arr)});console.log(list)

let users = [
    {"name": "张小花", "email": "zhang@qq.com"},
    {"name": "body", "email": "body@qq.com"},
    {"name": "李小璐", "email": "li@qq.com"}
];
let newEmail = users.map(function (item) {
    return item.name;
});
console.log(newEmail.join(','));

console.log([...'hello'])

var input = function(str, ...num) {
    console.log(str, num);
}