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JavaScript Asynchronous Programming with JavaScript Asynchronous JavaScript with Callbacks Implement a Callback

Crystal Vesely
Crystal Vesely
14,502 Points
Posted by Crystal Vesely
Crystal Vesely
14,502 Points

Why are we using let instead of const for the variable data?

I am trying to understand let vs const. I thought we’d use const for the variable data since data will not be changing within this function scope. So why are we using let?

1 Answer

Travis Alstrand
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Travis Alstrand
Treehouse Project Reviewer
Travis Alstrand
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Travis Alstrand
Treehouse Project Reviewer

Nice catch Crystal Vesely !

I'm sure the instructor didn't think too much about it as it wouldn't change anything in this particular example if it were let or const. However, you're correct, using const should be preferable here as it adheres to the principle of using the most restrictive declaration possible, which is a common best practice in modern JavaScript development.

But, they will both work fine in this exact situation. You can definitely use const in your code if you're following along.

Crystal Vesely
Crystal Vesely
14,502 Points
Crystal Vesely
Crystal Vesely
14,502 Points

Thanks for clearing that up. I just wanted to make sure I’m on the right thinking path.