---
id: 5d792533d31e4f7fad33011d
title: Part 9
challengeType: 0
isHidden: true
---
## Description
In `infixToFunction`, replace `addVar` with `(x, y) => x + y`.
## Instructions
## Tests
```yml
tests:
- text: See description above for instructions.
testString: assert(code.replace(/\s/g, '').match(/\+["']:\(x,y\)=>x\+y/));
```
## Challenge Seed
```html
```
### Before Test
### After Test
```html
```
## Solution