Offset elements in a JavaScript array

Have you ever needed to move some elements to the end of an array? While this sounds a little complicated, it's actually pretty simple.

As we generally avoid mutating arrays directly, we can create a new array with the elements moved to the end. This can be done by using Array.prototype.slice() to extract the elements before and after the specified index, and then combining them using the spread operator (...).

const offset = (arr, offset) => [...arr.slice(offset), ...arr.slice(0, offset)];

offset([1, 2, 3, 4, 5], 2); // [3, 4, 5, 1, 2]
offset([1, 2, 3, 4, 5], -2); // [4, 5, 1, 2, 3]

Note that if the offset is negative, the elements will be moved from the end to the start of the array.