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第 109 题：扩展题，请写出如下代码的打印结果 #33

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DreamLee1997 opened this issue Oct 6, 2019 · 0 comments

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DreamLee1997 commented Oct 6, 2019

var name = 'Tom';
(function() {
    if (typeof name == 'undefined') {
        name = 'Jack';
        console.log('Goodbye ' + name);
    } else {
        console.log('Hello ' + name);
    }
})();

解答：
Hello Tom
1、首先在进入函数作用域当中，获取name属性
2、在当前作用域没有找到name
3、通过作用域链找到最外层，得到name属性
4、执行else的内容，得到Hello Tom

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