In JS, why does the slice() documentation say it is a shallow copy when it looks like a deep copy?

Question

According to the docs for Array.prototype.slice() in JavaScript, the slice() method returns a shallow copy of a portion of an array into a new array. It is my under

Answer 1

slice is a shallow copy not because nested values are ignored, but because they contain references to the original arrays, and thus are still linked. For example:

let arr = [1, [2]]
let shallowCopy = arr.slice(0, arr.length);
shallowCopy[1][0] = "foobar";

// will print "foobar", because the nested array is just a reference
console.log(arr[1][0]);