Values Not Swapping: Use Destructuring Assignment to Assign Variables from Arrays

JavaScript
1

Tell us what’s happening:
Hey guys, I need some help in understanding why const [a, b] = [b, a] does not work but [a, b] = [b, a]works. I apologize if this is a bad question. Any help I can get would be greatly appreciated!

Your code so far
let a = 8, b = 6;

(() => {

“use strict”;

// change code below this line

const [b, a] = [a, b]

// change code above this line

})();

console.log(a); // should be 6

console.log(b); // should be 8


let a = 8, b = 6;
(() => {
  "use strict";
  // change code below this line
  const [a, b] = [b, a]
  // change code above this line
})();
console.log(a); // should be 6
console.log(b); // should be 8

Your browser information:

User Agent is: Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/69.0.3497.100 Safari/537.36.

Link to the challenge:
https://learn.freecodecamp.org/javascript-algorithms-and-data-structures/es6/use-destructuring-assignment-to-assign-variables-from-arrays

2

By declaring [a,b] as const you are attempting to re-declare a and b.
Since a and b are already declared you won’t need to declare them again.

1 Like
3

Oh, right. Thank you so much for your help! :grin: