/*  * 增加一层环境  */ function main(i){    return i}var demo = {}for(var i=0;i<5;++i){    ~function(){　　        var val = main(i);        demo[i] = function(){            return val        }    }()    }console.log(demo[4]())

/*  *  while 循环也一样  */ function main(i){    return i}var demo = {};var i = 5;while(i--){    ~function(){        var val = main(i);        demo[i] = function(){            return val        }    }()    }console.log(demo[1]())

/*  * 经典的闭包  */ var i = 0, lis = document.getElementsByTagName('li'), val;while(val = lis[i++]){    ~function(){        var temp = i;        val.onclick = function(){            console.log(temp)        }    }();}