JavaScript块作用域的相关内容

文章 2023-04-23 来自：开发者社区

深入理解javascript块作用域

前言上一章我们介绍到，javascript中的作用域就像一个个小“气泡”，而函数作用域就是其中的一种产生方式，每声明一个函数都会为其自身创建一个气泡，属于这个函数的全部变量都可以在整个函数的范围内使用及复用，这一章我们将介绍javascript作用域的另一种小“气泡”，块作用域正文块作用域在ES6之前，除 J....

文章 2021-11-13 来自：开发者社区

「注解」《你不知道的JavaScript（上卷）》第三章：函数作用域和块作用域

函数中的作用域隐藏内部实现为什么不将所有的变量和函数都放在全局作用域中？规避冲突隐藏作用域中的变量和函数可以避免同名标识符之间的冲突。全局命名空间很多第三方库为了防止变量冲突，通常会为变量命名一个非常独特的名字。模块管理函数作用域立即执行函数是一种既不需要函数名同时能够自动执行的函数。匿名和具名区分匿名函数表达式和函数声明：函数声明需要函数名，但是函数表达式则不需要。匿名函数表达式有以下几个缺点....

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更新时间 2023-05-05 14:24:39

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