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re: 15 must-know JavaScript array methods in 2020 VIEW POST

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re: Nice article. But I am confused what is the difference between map and forEach? Output looks the same.
 

map() takes a function as argument which will run on all elements on the array (getting a transformed value), and then return a new array with all transformed values.
If we run the following array through .map(x => x + 1) we get:

[1, 2, 3]
 |  |  |
 v  v  v
[2, 3, 4]

forEach() will just iterate on the array. Its return value is undefined.

Neither function will mutate the original array.

 

Great explanations and examples. Thanks again

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