关于return返回值的四种情况

1.

function a(){
   var wait=function(){
      console.log("222");
      return "333";
   };
   console.log("111");
   return wait();
}
var w=a();
console.log(w);

2.

function a(){
   var wait=function(){
      console.log("222");
      return "333";
   };
   console.log("111");
   wait();
}
var w=a();
console.log(w);

3.

function a(){
 var wait=function(){
 console.log("222");
 //return "333";
 };
 console.log("111");
 wait();
 }
 var w=a();
 console.log(w);

4.

function a(){
   var wait=function(){
      console.log("222");
      //return "333";
   };
   console.log("111");
   return wait();
}
var w=a();
console.log(w);