當(dāng)函數(shù)的返回值是一個引用數(shù)據(jù)類型并且被其他變量所引用，那么該函數(shù)就不會被釋放了

function fn() {
            var i = 10;
            return function(n) {
                console.log(n+(++i));
            }
        }

        var f = fn();
        f(10);
        f(20);
        fn()(10);
        fn()(20);

2. 自執(zhí)行函數(shù)中的dom的點(diǎn)擊事件會讓自執(zhí)行函數(shù)不銷毀

var sp = document.getElementById('click');
    var ip = document.getElementById('inp');
    ~function(){
        var count = 1;
        sp.onclick = function() {
            
            ip.value = count++;
        }
    }();

sp.onclick = (function(){
        var count = 0;
        return function(){
            alert('hah');
            ip.value = count++;
        }
    })();

比較好的方法

sp.count = 0;
sp.onclick = function(){
    sp.innerhtml = ++this.count;
}