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How do you know when to use different types of loops? (i.e. for...of vs. for vs. while)

Will
An ex-liberal arts major getting started on the developer journey.
・1 min read

Hey all!

Recently, I've been studying loops in JavaScript and was wondering if more experienced developers could give some examples of when to best use each of them. For example, when should I use a for loop vs. a while loop or vice versa?

Thanks!

Discussion (2)

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terabytetiger profile image
Tyler V. (he/him)

The way I've always decided is that for loops are for "known" lengths and while loops are for "unknown" lengths.

To break this down further - if you have an array and need to loop over each element of the array, you can use for (item of array). We know it's going to be a for loop because we want to hit each element 1 time over the course of our loop.

If we wanted to add items to an array until the length of the array was 100 or more items, we could use while (array.length < 100) - the big thing here is that we don't know how long our array will be when it starts.

Does that clarify things?

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will_i_am_a_dev profile image
Will Author

It does, thanks so much!