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作用域·测试题 #107

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smileyby opened this issue Jun 17, 2021 · 2 comments

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测试题 💫 JavaScript ☀️

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smileyby commented Jun 17, 2021

变量提升函数foo（声明+定义）
function foo(){} 这一行执行时，浏览器会把这一行之前对foo的操作，不仅认为是私有的，也会给全局映射一份；在之后的操作都认为是私有的（此操作是为了：兼容ES3和ES6）
foo = 1,块级作用于中的foo赋值为1
输出全局下的 foo ，结果为 function foo(){}

smileyby added JavaScript ☀️ 测试题 💫 labels

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smileyby commented Jun 17, 2021

Owner Author

smileyby commented Jun 18, 2021

以上代码的输出结果取决于，浏览器是否可以识别块级作用域

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