function foo(){
     let a = 10;
     const name = "xin"
     function bar(){
          console.log(`hello!,${a}haha${name}`);
     }
     return bar;
}
var fo = foo();
fo();

const info = (function(){
     const age = 21;
     const name = "xin";
     const love = "i love you";
     function xf(){
          console.log(` my age is ${age},and i will tell you ${love}!`);
     }
     function xx(){
          console.log("come on baby!")
     }
     return{
          say:xf,
          tell:xx
     }

})()
info.say();
info.tell();