closures - uninitialized vs undefined

Nadie ha tomado este issue todavía.

in [this article](https://javascript.info/closure), we are discussing lexical environments, and the scope of variables.
upon initialization, variables are defined as `` because "[the engine knows about the variable, but it cannot be referenced until it has been declared with `let`](https://javascript.info/closure#step-1-variables)"

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.

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.

Comienza por las secciones sobre entorno léxico y funciones anidadas del artículo sobre closures y, después, compara las etiquetas de lexenv-nested-makecounter-2.svg y lexenv-nested-makecounter-3.svg. Verifica si los diagramas deberían distinguir de undefined y actualiza esos SVGs únicamente si el comportamiento de JavaScript respalda la corrección propuesta.

Escrito por el modelo de indexación a partir del texto del issue.