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let, const, and my view

EmNudge on December 26, 2019

"Well this isn't going to be a controversial post" he said, wrongly. For those unaware, the title is in reference to a little discussion that span...

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Avi Aryan • Dec 26 '19 • Edited

Same here.

By default, I write const and then only switch to let if I need to change a variable. If you write code functional programming style (which is better IMO), you won't be using let. I almost don't use let at all.

Ben Sinclair • Dec 26 '19

As mentioned before, const only serves to make a constant binding, not data structure, but that is not immediately obvious to a beginner.

I don't use JS as my main language, but I've been using it since corduroy was cool and that wasn't obvious to me.

drew • Dec 28 '19

Nice post. I'm still a newbie learner, so I'll have to google some things, but overall this made sense. I've been a bit confused over this, and I think a lot of courses on Udemy are teaching let over const, but from the viewpoint of skimming code and expecting a change with let, that makes a lot of sense. Gonna bookmark this post and come back to it when I pick up JS again. Thanks.

EmNudge • Dec 28 '19 • Edited

I'm glad you found my post so helpful!

As an aside, my posts are usually aimed at people who already know quite a bit, but I try to also add some language for people who are new, but extra curious.

The fact that you still understood it means a lot to me!

Jeroen Rombouts • Dec 28 '19

I used to think like you. Then I started working in an environment where I'm about the only real front-end developer and the others are repurposed WinForms developers. You don't want to know how many times I get the question why their const can be mutated.

So, yes, in theory you're right. In some environments, however, prefer-let makes more sense. I'm all for changing your approach based on your environment and/or project instead of thinking in absolutes.