ES6 箭头函数

1.缩减代码

function double(number){
        return number*2;
       }
       console.log(double(20))

       const double2 = number => number*2;
       console.log(double2(15))

2.改变this指向  （this 始终指向调用它的对象  ES6中箭头函数的this指向函数上边的对象）

       let team = {
           tName:"man",
           people:['jack','jerry'],
           order:function(){
               return this.people.map(people => {
                    return `${people}隶属于${this.tName}小组`;
               });
           }
       }
       console.log(team.order());  //["jack隶属于man小组", "jerry隶属于man小组"]