ecmascript-6 - 为什么我应该在函数内部使用 let 而不是 const？

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我在我的项目中为 js (es6) 添加了 linter，对于新配置，我发现它们阻止使用 const内部函数 - 仅适用于模块级常量。我应该使用内部函数let .但我找不到任何理由来支持这种规则。为什么？
例如，对于 jscs

disallowConstOutsideModuleScope: const should only be used in module scope (not inside functions/blocks)

我知道我可以配置和关闭该规则，我只是想知道它启用了什么？这种检查的动机是什么？
附言我有链接 https://madhatted.com/2016/1/25/let-it-be带有 block “常量常量”

There is another school of thought on when to use let and const I’ll need to address. This strategy suggests developers use const as much as possible. Any variable that is not re-assigned should be declared with const.

I think this usage is poor practice. It adds an extra distraction to the process of programming, and results in code difficult to understand and change.

但我找不到这些论点有值(value)

Answer 1

这只是一个编码指南。他们关注 this思想学校。如果您不想使用它，请随时在您的 .jscsrc 中将其关闭。文件。要点是:

1. Aggressive use of const devalues the operator
2. Choosing const first really means choosing to think about every declaration. Will the next line of code change this assignment? How will I use this variable?
3. There is no known performance difference between let and const.