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

Array Iterator Array.map() creates the new array with the same number of elements or does not change the original array. There might be the problem with referencing if there is object inside the array as it copies the same reference, so, when you are making any changes on the property of the object it will change the original value of the element which holds the same reference.

The solution would be to copy the object, well, array.Splice() and [...array](spread Operator) would not help in this case, you can use JavaScript Utility library like Loadash or just use below mention code:

const newList = JSON.parse(JSON.stringify(orinalArr))