Use the Rest Operator with Function Parameters!---

Tell us what’s happening:

Your code so far

const sum = (function() {
  "use strict";
  return function sum(x, y, z) {
    const args = [ x, y, z ];
    return args.reduce((a, b) => a + b, 0);
console.log(sum(1, 2, 3)); // 6

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User Agent is: Mozilla/5.0 (Windows NT 10.0; Win64; x64) AppleWebKit/537.36 (KHTML, like Gecko) Chrome/77.0.3865.90 Safari/537.36.

Link to the challenge:

please tell us what’s happening or we are not able to tell what kind of help you need

You have to use the rest operator so that the function can take any number of arguments. If you use (x, y, z) then there will only ever be three arguments.

1 Like

We need a function sum, that can take any numbers of args. Instead of sum parameters x, y, z we can use a rest operator: sum(…args). After that we don’t need to introduce any array containing that three members x, y and z and we should delete that line with const args.