---
id: 5d79253386060ed9eb04a070
title: Step 017
challengeType: 0
isBeta: true
---
## Description
The `match` parameter is currently unused, which can lead to unused variable warnings in some linters.
To fix this, prefix or replace it with an underscore (`_`) - both ways signal to the reader and linter that you're aware you don't need this.
Note that a single underscore can only be used once in a function and may conflict with some libraries (Lodash, Undrescore.js).
## Instructions
## Tests
```yml
tests:
- text: See description above for instructions.
testString: assert(code.replace(/\s/g, "").includes("str.replace(regex,(_"));
```
## Challenge Seed
```html
```
### Before Test
### After Test
```html
```
## Solution