作用域链云解析DNS 的相关内容

文章 2024-10-16 来自：开发者社区

作用域和作用域链及预解析

变量---->局部变量和全局变量, 作用域：在某个空间范围内，可以对数据进行读写操作局部作用域和全局作用域 js中没有块级作用域—一对括号中定义的变量,这个变量可以在大括号外面使用函数中定义的变量是局部变量作用域链:变量的使用,从里向外,层层的搜索,搜索到了就可以直接使用了层层搜索,搜索到0级作用域的时候,如果还是...

问答 2022-04-01 来自：开发者社区

JavaScript中构造函数导致的不同的作用域链和标识符解析怎么理解？

JavaScript高级程序设计中的6.2.2(p.146)中提到，构造函数模型有这样一个问题：以这种方式创建函数，会导致不同的作用域链和标识符解析，但创建的Function新实例的新机制仍然是相同的。这句话该如何理解呢？

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更新时间 2024-10-17 09:13:17

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