Immutable Array Element Modification in JavaScript
Let's now learn how to perform immutable modification of elements in an array. For example, let's say we have some array:
let arr = [1, 2, 3, 4, 5];
Let the index for modification
be stored in variable ind:
let ind = 3;
Let's modify the element at the given index. According to our approach, we should make a copy of the array and modify the element in the copy. Let's do this:
let copy = Object.assign([], arr);
copy[ind] = '!';
let res = copy;
Let's use the second approach:
let res = [
...arr.slice(0, ind),
'!',
...arr.slice(ind + 1)
];
Create a button that, when clicked, will modify an array element. Let the index of the element to be modified be stored in a variable.
