---
id: 646d45ee725632cca2555146
title: Step 88
challengeType: 0
dashedName: step-88
---
# --description--
Now your `applyFunction` needs to return a result. Return the result of calling the `.replace()` method on `str2`. Pass your `functionCall` regex and an empty callback.
# --hints--
Your `applyFunction` function should return the result of calling the `.replace()` method on `str2`.
```js
assert.match(code, /const\s+applyFunction\s*=\s*(?:\(\s*str\s*\)|str)\s*=>\s*\{\s*const\s+noHigh\s*=\s*highPrecedence\(\s*str\s*\)\s*;?\s*const\s+infix\s*=\s*\/\(\[(?:\\d\.|\.\\d)\]\+\)\(\[(?:\+-|-\+)\]\)\(\[(?:\\d\.|\.\\d)\]\+\)\/\s*;?\s*const\s+str2\s*=\s*infixEval\(\s*noHigh\s*,\s*infix\s*\)\s*;?\s*const\s+functionCall\s*=\s*\/\(\[a-z0-9\]\*\)\\\(\(\[0-9\., \]\*\)\\\)\(\?!\.\*\\\(\)\/i\s*;?\s*const\s+toNumberList\s*=\s*(?:\(\s*args\s*\)|args)\s*=>\s*args\.split\(\s*('|"|`),\1\s*\)\.map\(\s*parseFloat\s*\)\s*;?\s*const\s+apply\s*=\s*\(\s*fn\s*,\s*args\s*\)\s*=>\s*spreadsheetFunctions\s*\[\s*fn\.toLowerCase\(\s*\)\s*\]\s*\(\s*toNumberList\(\s*args\s*\)\s*\)\s*;?\s*return\s+str2\.replace\(/);
```
You should pass `functionCall` as the first argument to your `.replace()` call.
```js
assert.match(code, /const\s+applyFunction\s*=\s*(?:\(\s*str\s*\)|str)\s*=>\s*\{\s*const\s+noHigh\s*=\s*highPrecedence\(\s*str\s*\)\s*;?\s*const\s+infix\s*=\s*\/\(\[(?:\\d\.|\.\\d)\]\+\)\(\[(?:\+-|-\+)\]\)\(\[(?:\\d\.|\.\\d)\]\+\)\/\s*;?\s*const\s+str2\s*=\s*infixEval\(\s*noHigh\s*,\s*infix\s*\)\s*;?\s*const\s+functionCall\s*=\s*\/\(\[a-z0-9\]\*\)\\\(\(\[0-9\., \]\*\)\\\)\(\?!\.\*\\\(\)\/i\s*;?\s*const\s+toNumberList\s*=\s*(?:\(\s*args\s*\)|args)\s*=>\s*args\.split\(\s*('|"|`),\1\s*\)\.map\(\s*parseFloat\s*\)\s*;?\s*const\s+apply\s*=\s*\(\s*fn\s*,\s*args\s*\)\s*=>\s*spreadsheetFunctions\s*\[\s*fn\.toLowerCase\(\s*\)\s*\]\s*\(\s*toNumberList\(\s*args\s*\)\s*\)\s*;?\s*return\s+str2\.replace\(\s*functionCall/);
```
You should pass an empty arrow function as the second argument to your `.replace()` call.
```js
assert.match(code, /const\s+applyFunction\s*=\s*(?:\(\s*str\s*\)|str)\s*=>\s*\{\s*const\s+noHigh\s*=\s*highPrecedence\(\s*str\s*\)\s*;?\s*const\s+infix\s*=\s*\/\(\[(?:\\d\.|\.\\d)\]\+\)\(\[(?:\+-|-\+)\]\)\(\[(?:\\d\.|\.\\d)\]\+\)\/\s*;?\s*const\s+str2\s*=\s*infixEval\(\s*noHigh\s*,\s*infix\s*\)\s*;?\s*const\s+functionCall\s*=\s*\/\(\[a-z0-9\]\*\)\\\(\(\[0-9\., \]\*\)\\\)\(\?!\.\*\\\(\)\/i\s*;?\s*const\s+toNumberList\s*=\s*(?:\(\s*args\s*\)|args)\s*=>\s*args\.split\(\s*('|"|`),\1\s*\)\.map\(\s*parseFloat\s*\)\s*;?\s*const\s+apply\s*=\s*\(\s*fn\s*,\s*args\s*\)\s*=>\s*spreadsheetFunctions\s*\[\s*fn\.toLowerCase\(\s*\)\s*\]\s*\(\s*toNumberList\(\s*args\s*\)\s*\)\s*;?\s*return\s+str2\.replace\(\s*functionCall\s*,\s*\(\s*\)\s*=>\s*\{\s*\}/);
```
# --seed--
## --seed-contents--
```html