why a js map on an array modify the original array?

Question

I\'m quite confuse by the behaviour of map().

I have an array of objects like this :

const products = [{
    ...,
    \'productType\' = \'premium\',         


        

Answer 1

To elaborate on SimpleJ's answer - if you were to === the two arrays, you would find that they would not be equal (not same address in memory) confirming that the mapped array is in fact a new array. The issue is that you're returning a new array, that is full of references to the SAME objects in the original array (it's not returning new object literals, it's returning references to the same object). So you need to be creating new objects that are copies of the old objects - ie, w/ the Object.assign example given by SimpleJ.