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closures - uninitialized vs undefined #3895

@aredmondd

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@aredmondd

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"

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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.

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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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