function sum1(n1,n2){
    return n1+n2;
  };

var sum2=function(n1,n2){
    return n1+n2;
};

(function(n1,n2){
    console.log (n1+n2)
})(1,3);//4

  //可用来传参
  (function(x,y){
    console.log(x+y);
  })(2,3);

  //带返回值
  var sum=(function(x,y){
    return x+y;
  })(2,3);
  console.log(sum);

  ~function(){
    var name='~'
    console.log(name);
  }();

  !function(){
    var name='!'
    console.log(name);
  }();

  ;(function(){
    var name=';'
    console.log(name);
  })();

  -function(){
    var name='-'
    console.log(name);
  }();

  //逗号运算符
  1,function(){
    var name=',';
    console.log(name);
  }();

  //异或
  1^function(){
    var name='^';
    console.log(name);
  }();

  //比较运算符
  1>function(){
    var name='>';
    console.log(name);
  }();

  ~+-!(function(){
    var name='~+-!';
    console.log(name);
  })();

  ~!(function(){
    var name='~!';
    console.log(name);
  })();

  (function(){
    var name='call';
    console.log(name);
  }).call();

  (function(){
    var name='apply';
    console.log(name);
  }).apply();

var sum3=new Function('n1','n2','return n1+n2');
console.log(sum3(2,3));//5

var name='haoxl';
  function fun(){
    var name='lili';
    return new Function('return name');//不能获取局部变量
  }
 console.log(fun()());//haoxl