closures - uninitialized vs undefined

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javascript
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documentation

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先从 closure 文章中关于词法环境和嵌套函数的部分开始，然后比较 lexenv-nested-makecounter-2.svg 和 lexenv-nested-makecounter-3.svg 中的标签。验证这些图是否应将 与 undefined 区分开来，并且仅在 JavaScript 的行为支持所提议的修正时更新这些 SVG。

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描述

in this article, we are discussing lexical environments, and the scope of variables.
upon initialization, variables are defined as <unitialized> because "the engine knows about the variable, but it cannot be referenced until it has been declared with let"

Image Image

later in the article, when referencing nested lexical environments in functions, a variable is initialized as undefined. from my understanding, this is incorrect, as the engine knows about the variable, but is not referenced yet since it hasn't been declared.

Image Image

i believe that we need to change the following SVG's to reflect this change:
https://github.com/javascript-tutorial/en.javascript.info/blob/master/1-js/06-advanced-functions/03-closure/lexenv-nested-makecounter-2.svg
https://github.com/javascript-tutorial/en.javascript.info/blob/master/1-js/06-advanced-functions/03-closure/lexenv-nested-makecounter-3.svg

if this is an incorrect assumption, please help me understand why it's undefined instead of uninitialized! i'd love to learn more about how this all works.

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