Variable Scope in Modern JavaScript

It often surprises me when speaking to other JavaScript developers how many are unaware of how variable scope works in the language they code in. By scope we are talking about the visibility of variables in our code; or in other words which parts of the code can access and modify a variable. I regularly find people declaring variables with var in the middle of code, not knowing how JavaScript will

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`var`、`let`、`const`の変数のスコープについて解説している記事。