Swapping two array elements in a single line using JavaScript

In JavaScript, there exist many ways using by which one can swap two array elements. In this article, we will discuss a way in which one can swap two array elements in JavaScript in a single line. The input and output would be as follows.

Input: arr = { 10, 20, 40, 30 }
Output: arr = { 10, 20, 30, 40 } 
// Swapped 30 and 40

This swapping can be done by writing the 2 array elements we want to reverse in order and in square brackets on the left-hand side. On the right-hand side we will write the same array elements but this time in reverse order.

Syntax:

[a[m], a[n]] = [a[n], a[m]] 
 
// where m and n are the index numbers to swap

Example 1:

Javascript

<script>
  let arr = [1, 2, 3, 5, 4];

  // Swapping element at index 3 with index 4
  [arr[3], arr[4]] = [arr[4], arr[3]]

  // Print the array
  console.log(arr)
</script>

Output:

[1, 2, 3, 4, 5]

Example 2:

Javascript

<script>
  let arr = ["e", "b", "c", "d", "a"];

  // Swapping element at index 0 with index 4
  [arr[0], arr[4]] = [arr[4], arr[0]];

  // Print the array
  console.log(arr);
</script>

Output:

['a','b','c','d','e']

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