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Comment by mikekchar | Hacker News Reader

The only reason I can think of is if you want hoisting for some reason. For example, if you want to call functions before they are declared. Personally, I don't like that style, but some people do.

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Function declarations work like this

  typeof myFn === 'function'; // true
  function myFn() { }

let / const are both hoisted though, they're just hoisted to the top of the current block scope instead of function scope.

Sort of, but the effect is very different due to the "temporal dead zone." Attempting to access a variable declared with `let/const` or const before the declaration will throw an error, vs just getting `undefined` for a variable declared with `var`.

I'm a bit confused. What does "hoisted" mean in this context if accessing the variable before declaration will throw an error?

From the MDN docs:

"In ECMAScript 2015, let bindings are not subject to Variable Hoisting, which means that let declarations do not move to the top of the current execution context."

https://developer.mozilla.org/en-US/docs/Web/JavaScript/Refe...

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