How Can I Efficiently Rotate Array Elements in JavaScript?

Rotating Array Elements in JavaScript

Efficiently rotating an array in JavaScript is a common task with various applications. One common approach is to use the array's built-in methods, such as unshift() and splice().

One implementation of a rotation function, which rotates the array to the right, is:

Array.prototype.rotateRight = function(n) {
  this.unshift.apply(this, this.splice(n, this.length));
  return this;
}

This function can be used as follows:

var months = ["Jan", "Feb", "Mar", "Apr", "May", "Jun", "Jul", "Aug", "Sep", "Oct", "Nov", "Dec"];
months.rotateRight(new Date().getMonth());

An alternative approach, using push() and pop(), is:

function arrayRotate(arr, reverse) {
  if (reverse) arr.unshift(arr.pop());
  else arr.push(arr.shift());
  return arr;
}

Its usage is:

arrayRotate([1, 2, 3, 4, 5]);       // [2, 3, 4, 5, 1];
arrayRotate([1, 2, 3, 4, 5], true); // [5, 1, 2, 3, 4];

It is worth noting that the provided solutions do not support rotations by a specific count. If this functionality is required, further modifications to the functions may be necessary.

Currently, there is no known JavaScript framework with a built-in array rotation function.

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